Diabetes

• General Info about Diabetes
• Causes Of Diabetes
• Symptoms
• diagnoses of Diabetes
• More Valuable information about Diabetes
• Questions About Diabetes
• Glossary
• Diabetes,General
• Preventing Diabetes
• Diabetes Overview
• Diabetes Symptoms
• Diabetes Causes
• Diabetes Treatment
• Other Treatments 
• Study Describes Treatment Strategies for Pediatric Diabetes Complication
• Study Examines How Diabetes May Develop in Overweight People

General Info About Diabetes: 

It is, apart from being one of the most prevalent diseases in the world, also a disease that opens up a Pandora's box of many complications. No wonder it is a dreaded disease and people who are diabetic end up getting other medical problems as well. Diabetes is a group of diseases with one thing in common - a problem with insulin. The problem could be that your body doesn't make any insulin, doesn't make enough insulin or doesn't use insulin properly.

Diabetes is a wonderful affection, not very frequent among men, being a melting down of the flesh and limbs into urine. The patients never stop making water, but the flow is continual, as if from the opening of aqueducts. The nature of the disease, then, is chronic, and it takes a long period to form; but the patient is short-lived, if the constitution of the disease be completely established; for the melting is rapid, the death speedy.

The pancreas, which is an organ present in the abdominal cavity of the body, secretes this hormone insulin. This hormone is the key to the way your body processes food because it helps maintain the proper level of a sugar (glucose) in your blood. Glucose is your body's fuel. Cells use glucose to produce energy to grow and function. Glucose is escorted by insulin through your bloodstream and insulin helps in unlocking cells to allow glucose to enter.

In diabetes, lack of insulin or the resistance of your cells to insulin prevents the right amount of glucose from entering your cells. The unused glucose builds up in your blood, a condition called hyperglycemia.

The disease occurs in two types: Type 1 diabetes: This is the type of diabetes that generally affects young people and requires treatment with insulin.

Type 2 diabetes: This type of diabetes generally develops after age 40. Diabetes can develop gradually, often without symptoms, over many years. It may reveal itself too late to prevent damage. In fact, you may first learn you have diabetes when you develop one of its common complications - heart disease, kidney disease or vision problems. Today, better methods of diabetes control, new medications and easier ways to take insulin enable most people who develop type 1 or 2 diabetes to live a long and healthy life.

Causes Of Diabetes:

The various types of diabetes are different disorders with different causes:

Type 1 diabetes :- This type of diabetes is an autoimmune disease. Your immune system turns on itself and destroys the insulin-producing cells in your pancreas. Although type 1 diabetes usually develops in childhood or teen years, it can appear later.

Type 2 diabetes :- In this type, your pancreas makes some insulin, but not enough. Your cells also can become resistant to insulin's effects, keeping insulin from escorting enough glucose into your body's cells. Type 2 diabetes generally develops after age 40. However, doctors are seeing a rise in childhood type 2 diabetes that parallels the rise in obesity among youth. A form of type 2 diabetes, gestational diabetes, develops during 2 percent to 5 percent of pregnancies. In gestational diabetes, your body doesn't effectively use the insulin you produce. The cause may be metabolic changes that occur due to the effects of hormones in pregnancy. Gestational diabetes usually disappears after pregnancy, but more than half of women who experience it eventually develop a permanent type 2 diabetes.

Symptoms:

The symptoms are due to persistent high levels of sugar in the circulating blood. These symptoms are:

• Frequent urination - When blood sugar is too high, your kidneys can't absorb the excess glucose. The glucose leaks into urine, pulling water with it.
• Extreme thirst - The process of dehydration makes you thirsty.
• Blurry vision - High blood sugar may cause new blood vessels to form and may damage old blood vessels on the retina at the back of your eye.
• Weight loss - To make up for the lost fuel, your body burns fat reserves, and you may lose weight.
• Fatigue - When your cells don't get enough glucose, their primary fuel source, fatigue results.
• Hunger - Burning of fat reserves also may make you hungry.

How Can We Diagnose Diabetes?

If you have a family history of diabetes and also suffer from some of the risk factors mentioned above, then it is always advisable to screen yourself regularly to detect diabetes and avoid the serious complications. As the saying goes " Prevention is better than cure". So it is always advisable to screen yourself for diabetes if you stand the risk of suffering from it. If you're at risk of diabetes or have symptoms, you should take the test at a younger age and more frequently.

A fasting plasma glucose test is a simple, reliable test for diagnosing diabetes. After fasting overnight (or for 8 hours), a sample of your blood is drawn to measure the glucose level. Most people have a level between 70 and 100 milligrams of glucose per deciliter of blood (mg/dL).

A level of 126 mg/dL or higher on two tests confirms a diagnosis of diabetes. Your doctor may diagnose diabetes if you have a single very high fasting blood glucose level or a higher glucose level along with diabetes symptoms.

How can Diabetes be treated ? 

Controlling blood sugar is the single most important thing you can do to prevent long-term complications of diabetes.

If you have type 1 diabetes, you must take insulin. Before its discovery in 1921, people with type 1 diabetes usually died within a year or two. Today, most people use synthetic insulin, which is chemically identical to human insulin.

If you have type 2 diabetes, you may be able to control your blood sugar with weight control, diet and exercise. Or, you may need to combine these approaches with medication.

Medications to treat type 2 diabetes include:

Sulfonylurea drugs: These medications lower blood sugar levels by stimulating your pancreas to produce and release more insulin. Sulfonylurea drugs that doctors commonly prescribe include glipizide and glyburide.

Metformin: This drug decreases the release of glucose stored in your liver.

Acarbose: This medication helps decrease the after-meal spike in your blood sugar level by slowing the digestion and absorption of carbohydrates in your intestine.

Insulin sensitizers: These new oral drugs improve your body's response to insulin, making your body more sensitive to the insulin that's already available. These medications can help reduce or eliminate the need for insulin injections in some people.

If you have type 2 diabetes, you may need to start taking insulin if fasting blood glucose levels stay above goals set by your doctor. How much insulin you need depends on your age, weight, exercise level, type of diabetes and how difficult your blood sugar is to control.

More Valuable information about Diabetes... 

 Unlike other diseases, diabetes cannot be cured as such. This can be controlled and the person affected with diabetes can afford to have a normal life if he or she manages to keep the blood sugar levels within permissible levels. Many factors - diet, alcohol, activity, stress, illness, medications and changes in hormone levels - can affect your blood sugar. But you can monitor your level with frequent blood glucose self-testing. These tests are available over-the-counter at pharmacies. You prick the tip of your finger and touch a drop of your blood to a strip of paper. You compare the color on the strip of paper to a chart to determine your blood sugar level. Knowing the level of sugar in your blood helps you learn what makes your blood sugar levels rise and fall, so you can adjust your treatment.

Changes in your routine can cause swings in your blood sugar level. Here are suggestions for how to handle factors that affect your level:

Balance your diet and medications If you take diabetes medications, be consistent on a day-to-day basis in the timing and amount of food you eat. By controlling when you eat and how much, you control the times your blood sugar is higher, such as after meals, and how high or low your blood sugar level goes. Whenever you go off schedule, you risk upsetting the balance between your diet and your medication. Too little food in comparison to your medication may result in very low blood sugar and a hypoglycemic reaction. Too much food, and your blood sugar will be too high.

Test yourself after exercising Exercise usually lowers your blood sugar level for several hours. But exercise can also increase your blood sugar if your insulin level is too low. Until you know how your body responds to exercise, test your blood glucose just after exercising and then again several hours later.

Monitor the effects of stress and illness Psychological stress or the physical stress of a cold, influenza (flu) or a bacterial illness can cause your body to produce hormones that prevent insulin from working properly. Major trauma or other medical problems, such as a heart attack, also can increase blood sugar levels dramatically. During times of stress and illness, it's important to monitor blood glucose frequently. You should also have a vaccination against pneumococcal pneumonia and a yearly flu shot.

Avoid alcohol Alcohol prevents the release of glucose from your liver and can increase the risk of your blood sugar falling too low. If you drink alcoholic beverages, do so only in moderation, and eat food before you have a drink.

Questions About Diabetes... 

How to identify gestational diabetes? Several symptoms are associated with the disease and they may vary from patient to patient. Increased thirst and urination, weight loss despite of increased appetite, frequent infections including bladder, vaginal, and skin are among the symptoms.

How insulin helps diabetes? Insulin lowers blood sugar by allowing it to leave the blood stream and enter the cells. People with type I diabetes cannot make their own insulin in the body and must take insulin injections to meet the regular requirement. They can survive without insulin injections, but many may take insulin injections to control blood glucose levels more effectively. Insulin is taken as an injection. Patients who need insulin is taught to give his/her injections themselves.

In type II diabetes, the patient's body makes insulin, but is not able to use it effectively. They use medicines to control blood sugar in the form of pills, usually once or twice a day. These medicines work by preventing the body from sending sugar into the bloodstream when the naturally produced insulin is not working properly, releasing more Insulin into the bloodstream, and helping the body's own insulin move glucose from the bloodstream into the cells. Some people need insulin in addition to oral medicines. Some people no longer need medicines if they lose weight because their own insulin output is sufficient after reducing weight, fat, and sugar.

Insulin is taken as an injection. It is not available in tablet form.

What to eat when your blood sugar level is not normal? Diet planning for diabetes includes choosing healthy foods, eating the right amount of food at the right time. Meal plans differ depending on the type of diabetes. If meals and insulin are out of balance, extreme variations in blood glucose can occur.

In Non insulin-dependent diabetes (Type II), weight control is the most important principle in addition to a well-balanced diet. The doctor and dietician will help you to chalk out a diet plan to follow.

What happens if you miss a dose of insulin? In insulin-dependent diabetics when a dose of insulin is missed or if infection is present, weakness, drowsiness, headache, double vision, lack of coordination and convulsions or unconsciousness can occur.

Why diabetics should give more care to their feet? People with diabetes are prone to foot problems because of complications caused by damage to large and small blood vessels and nerves, and decreased ability to fight infection. To prevent injury to the feet, diabetics should regularly checkup their feet.

Do sugars cause diabetes? So far the researchers do not know why diabetes occurs, but they know sugars do not cause it. During physical activity, they are the main energy source.

Diabetes is a disorder in the way the body handles sugars. People with diabetes do not make enough insulin. Or they cannot use the insulin their bodies do make.

Glossary

Hyperglycemia - High a level of glucose in the blood; a sign that diabetes is out of control. Many things can cause hyperglycemia. It occurs when the body does not have enough insulin or cannot use the insulin it does have to turn glucose into energy. Signs of hyperglycemia are great thirst, a dry mouth, and a need to urinate often. For people with insulin-dependent diabetes, hyperglycemia may lead to diabetic ketoacidosis.

Hyperosmolar Coma -A coma (loss of consciousness) related to high levels of glucose (sugar) in the blood and requiring emergency treatment. A person with this condition is usually older and weak from loss of body fluids and weight. The person may or may not have a previous history of diabetes. Ketones (acids) are not present in the urine.

Insulin - A hormone by the Pancreas. Insulin promotes glucose/sugar utilization and protein synthesis.

Pancreas - This is an elongated lobular shaped organ found in the abdomen starting from the first part of the small intestine.

Metabolism - A bio-chemical process through which energy consumption and energy production is carried out in cells.

Ketones - The end products of fat metabolism.

Diabetes, General 

Related Terms

• Diabetes, Prevention, Diabetes, Nutritional Depletion Principal Proposed Natural Treatments
• Blood Sugar Control: Aloe, Chromium, Fenugreek, Ginseng, Gymnema
• To Correct Nutritional Deficiencies: Calcium, Magnesium, Manganese, Taurine, Vitamin B, Vitamin C, Zinc
• Complications of Diabetes: See associated article Other Proposed Natural Treatments
• Blood Sugar Control: Arginine, Ayurvedic Combination Herbal Therapies, Bilberry Leaf, Biotin, Bitter Melon, Caiapo, Carnitine, CLA (Conjugated Linoleic Acid), Coenzyme Q, Coccinia indica, Garlic, Glucomannan, Guggul, Holy Basil, Lipoic Acid, Magnesium, Niacinamide, Nopal Cactus, Onion, Pterocarpus, Salt Bush, Vanadium, Vitamin E Treatments to Use Only With Caution
• CLA (Conjugated Linoleic Acid), Ginkgo, Glucosamine

Conventional treatment for type 1 diabetes includes insulin injections and careful dietary monitoring. Type 2 diabetes may respond to lifestyle changes alone, such as increasing exercise, losing weight, and improving diet. Various oral medications are also often effective for type 2 diabetes, although insulin injections may be necessary in some cases.

Principal Proposed Natural Treatments

Several alternative methods may be helpful when used under medical supervision as an addition to standard treatment. They may help stabilize, reduce, or eliminate medication requirements; or correct nutritional deficiencies associated with diabetes. However, because diabetes is a dangerous disease with many potential complications, alternative treatment for diabetes should not be attempted as a substitute for conventional medical care.

Other natural treatments may be helpful for preventing and treating complications of diabetes, such as peripheral neuropathy, cardiac autonomic neuropathy, retinopathy and cataracts. See the article on complications of diabetes for more information.

Treatments for Improving Blood Sugar Control

The following treatments may be able to improve blood sugar control in type 1 and/or type 2 diabetes.

Note: Keep in mind that if these treatments work, you will need to reduce your medications to avoid hypoglycemia. For this reason, medical supervision is essential.

Chromium

Chromium is an essential trace mineral that plays a significant role in sugar metabolism. Some evidence suggests that chromium supplementation may help bring blood sugar levels under control in type 2 diabetes, but it is far from definitive.

A 4-month study reported in 1997 followed 180 Chinese men and women with type 2 diabetes, comparing the effects of 1,000 mcg chromium, 200 mcg chromium, and placebo.1 The results showed that HbA1c values (a measure of long-term blood sugar control) improved significantly after 2 months in the group receiving 1,000 mcg, and in both chromium groups after 4 months. Fasting glucose (a measure of short-term blood sugar control) was also lower in the group taking the higher dose of chromium.

A double-blind, placebo-controlled trial of 78 people with type 2 diabetes compared two forms of chromium (brewer's yeast and chromium chloride) against placebo.2 This rather complex crossover study consisted of four 8-week intervals of treatment in random order. The results in the 67 participants who completed the study showed that both forms of chromium significantly improved blood sugar control. Positive results were also seen in a double-blind, placebo-controlled study of 50 people with type 2 diabetes.139 However, some studies have failed to find benefit chromium helpful for type 2 diabetes.4,5

One placebo-controlled study of 30 women with gestational diabetes (diabetes during pregnancy) found that supplementation with chromium (at a dosage of 4 or 8 mcg chromium picolinate for each kilogram of body weight) significantly improved blood sugar control.6

Chromium has also shown a bit of promise for helping diabetes caused by corticosteroid treatment.7,8

For more information, including dosage and safety issues, see the full chromium article.

Fenugreek

The food spice fenugreek may also help control blood sugar. For millennia, fenugreek has been used both as a medicine and as a spice in Egypt, India, and the Middle East.

In a 2-month, double-blind study of 25 people with type 2 diabetes, use of fenugreek (1 g daily of a standardized extract) significantly improved some measures of blood sugar control and insulin response as compared to placebo.9 Triglyceride levels decreased and HDL (“good") cholesterol levels increased, presumably due to the enhanced insulin sensitivity. Similar benefits have been seen in animal studies and open human trials as well.10–12

For more information, including dosage and safety issues, see the full fenugreek article.

Gymnema

A few preliminary studies suggest that the Ayurvedic (Indian) herb gymnema may help improve blood sugar control.13–16 It might be helpful for mild cases of type 2 diabetes when taken alone or in combination with standard treatment (under a doctor's supervision in either case).

For more information, including dosage and safety issues, see the full gymnema article.

Ginseng

A double-blind study evaluated the effects of ginseng in 36 people newly diagnosed with or type 2 diabetes over an 8-week period.17 The results showed a reduction in glucose levels, improved HbA1c (a measure of long-term blood sugar control), and improved physical capacity. The authors believed that it was the increased activity that improved blood sugar.

Improved blood sugar control was also seen in two small double-blind, placebo-controlled trials using American ginseng (Panax quinquefolius).18,19 One study suggests that ginseng with low ginsenoside content is not effective.20

For more information, including dosage and safety issues, see the full ginseng article.

Aloe

The succulent aloe plant has been valued since prehistoric times as a topical treatment for burns, wound infections, and other skin problems. However, recent evidence suggests that oral aloe might be useful for type 2 diabetes.

Evidence from two human trials suggests that aloe gel can improve blood sugar control.

A single-blind, placebo-controlled trial evaluated the potential benefits of aloe in either 72 or 40 people with diabetes (the study report appears to contradict itself).21 The results showed significantly greater improvements in blood sugar levels among those given aloe over the 2-week treatment period.

Another single-blind, placebo-controlled trial evaluated the benefits of aloe in people who had failed to respond to the oral diabetes drug glibenclamide.22 Of the 36 people who completed the study, those taking glibenclamide and aloe showed definite improvements in blood sugar levels over 42 days as compared to those taking glibenclamide and placebo.

While these are promising results, large studies that are double- rather than single-blind will be needed to establish aloe as an effective treatment for improving blood sugar control.

Note that in the above we are referring to the gel of the aloe vera plant, and not the leaf skin (the latter is drug aloe, not aloe gel). However, some confusion has been introduced by the fact that some leaf skin may find its way into gel products, and that could be the actual active ingredient in aloe gel regarding diabetes.23,24 It is possible, therefore, that completely pure aloe gel might not work!

For more information, including dosage and safety issues, see the full aloe article.

Vanadium

Studies in rats with and without diabetes suggest that the mineral vanadium may have an insulin-like effect, reducing blood sugar levels.25–35 Based on these findings, preliminary studies involving human subjects have been conducted, with mostly promising results.36–41 However, this evidence is too limited to be taken as definitive proof.

For more information, including dosage and safety issues, see the full vanadium article.

Other Treatments That May Help Control Blood Sugar

Preliminary evidence suggests that the herbs bilberry leaf, bitter melon , Caiapo, Coccinia indica, garlic, guggul, holy basil (Ocimum sanctum), maitake, nopal cactus , onion, pterocarpus, and salt bush, and the supplements arginine, carnitine, glucomannan, lipoic acid, magnesium, and vitamin E might help control blood sugar levels.42–72,87–92,140–144Conjugated linoleic acid (CLA) has also shown promise in preliminary trials.73 Unexpectedly, however, one study found evidence that CLA might, under some circumstances, actually worsen diabetes rather than help it.74 (See Supplements to Use Only with Caution.)

Other herbs traditionally used for diabetes that might offer some benefit include Anemarrhena asphodeloides, Azadirachta indica, Catharanthus roseus, Cucurbita ficifolia, Cucumis sativus, Cuminum cyminum (cumin), Euphorbia prostrata, Guaiacum coulteri, Guazuma ulmifolia, Lepechinia caulescens, Medicago sativa, Musa sapientum L. (banana), Phaseolus vulgaris, Psacalium peltatum, Rhizophora mangle, Spinacea oleracea, Tournefortia hirsutissima, and Turnera diffusa.75–83

Combination herbal therapies used in Ayurvedic medicine have also shown some promise for improving blood sugar control.84–86

A double-blind study of more than 200 people evaluated the effectiveness of a a combination herbal formula used in traditional Chinese herbal medicine (Coptis Formula).145 This study evaluated Coptis Formula with and without the drug glibenclamide. The results hint that Coptis Formula may enhance the effectiveness of the drug, but that it is not powerful enough to treat diabetes on its own.

If your child has just developed diabetes, the supplement niacinamide—a form of niacin, also called vitamin B—might slightly prolong what is called the honeymoon period.93 This is the interval during which the pancreas can still make some insulin, and the body’s need for insulin injections is low. However, the benefits (if any) appear to be minor. A cocktail of niacinamide plus antioxidant vitamins and minerals has also been tried, but the results were disappointing.94 (See also Preventing Diabetes below.)

Massage therapy has shown some promise for enhancing blood sugar control in children with diabetes.

Treating Nutritional Deficiencies in Diabetes

Both diabetes and the medications used to treat it can cause people to fall short of various nutrients. Making up for these deficiencies (either through diet or the use of supplements) may or may not help your diabetes specifically, but it should make you a healthier person overall.

One double-blind study found that people with type 2 diabetes who took a multivitamin/multimineral supplement were less likely to develop an infectious illness than those who took placebo.147

People with diabetes are often deficient in magnesium,3,95,96 and one double-blind study suggests that magnesium supplementation may enhance blood sugar control.142 People with either type 1 or type 2 diabetes may also be deficient in the mineral zinc.97–99Vitamin C levels have been found to be low  in many people on insulin, even though they were consuming seemingly adequate amounts of the vitamin in their diets.Deficiency in taurine103 and manganese have also been reported.104

The drug metformin can cause vitamin B deficiency.105 Interestingly, taking extra calcium may prevent this.

Preventing Diabetes

Niacinamide

Evidence from a large study conducted in New Zealand suggests that the supplement niacinamide—a form of niacin, also known as vitamin B—might be able to reduce the risk of diabetes in children at high risk.107 In this study, more than 20,000 children were screened for diabetes risk by measuring certain antibodies in the blood (ICA antibodies, believed to indicate risk of developing diabetes), it turned out that 185 of these children had detectable levels. About 170 of these children were then given niacinamide for 7 years (not all parents agreed to give their children niacinamide or have them stay in the study for that long). About 10,000 other children were not screened, but they were followed to see if they developed diabetes.

The results were positive. In the group in which children were screened and given niacinamide if they were positive for ICA antibodies, the incidence of diabetes was reduced by almost 60%.

These findings suggest that niacinamide is an effective treatment for preventing diabetes. (The study also indicates that tests for ICA antibodies can very accurately identify children at risk for diabetes.)

At present, an enormous-scale, long-term trial called the European Nicotinamide Diabetes Intervention Trial is being conducted to definitively determine whether regular use of niacinamide can prevent diabetes. Results from the German portion of the study have been released, and they were not positive;108 however, until the entire study is complete, it is not possible to draw conclusions.

As noted above, a small trial evaluated the effects of niacinamide plus antioxidant vitamins and minerals for children who had just started to show signs of diabetes, and failed to find any benefits in terms of preventing the disease from worsening.109

Warning: Medical supervision is essential before giving your child long-term niacinamide treatment.

Vitamin D

Several observational studies suggest that vitamin D may also help prevent diabetes. However, studies of this type are far less reliable than double-blind trials.

For important information on dosage and safety, see the full vitamin D article.

Dietary Changes

The related terms “glycemic index" and “glycemic load" indicate the tendency of certain foods to stimulate insulin release. It has been suggested that foods that rank high on these scales, such as white flour and sweets, might tend to exhaust the pancreas, and therefore lead to type 2 diabetes. For this reason, low-carbohydrate and low glycemic-index diets have been promoted for the prevention of type 2 diabetes. However, the results from studies on this question have been contradictory, and far from definitive.

There is no question, however, that people who are obese have a far greater tendency to develop type 2 diabetes than those who are relatively slim; therefore, weight loss (especially when accompanied by increase in exercise) is clearly an effective step for prevention.

Supplements to Use Only with Caution

There is some evidence that the supplement glucosamine, used for osteoarthritis, may increase the risk of diabetic cataracts and possibly worsen blood sugar control.

In a double-blind, placebo-controlled study of 60 overweight men, use of conjugated linoleic acid (CLA) unexpectedly worsened blood sugar control.135 These findings surprised researchers, who were looking for potential diabetes-related benefits with this supplement. At present, therefore, people with diabetes should not use CLA except under physician supervision.

There are some indications that the herb ginkgo might alter insulin release in people with diabetes.136 The effect appears to be rather complex; the herb may cause some increase in insulin output, and yet might actually lower insulin levels overall through its effects on the liver and perhaps on oral medications used for diabetes. Until this situation is clarified, people with diabetes should use ginkgo only under the supervision of a physician.

Despite earlier concerns, vitamin B and fish oil appear to be safe for people with diabetes.

Finally, various herbs and supplements may interact adversely with drugs used to treat diabetes. For more information on this potential risk, see the individual drug articles in the Drug Interactions section of this database.

References

Diabetes is a disease of metabolism. Under normal circumstances, some of the food people eat is converted into glucose during digestion. Glucose is carried in the blood stream, and moved into cells – where it available as energy – through the action of a hormone called insulin. People with diabetes either do not produce enough insulin to move glucose into the cells, or the body is resistant to the insulin that is produced. In either case, the glucose builds up in the bloodstream until it is excreted in the urine.

According to the American Diabetes Association, the different types of diabetes are classified by the underlying insulin problem. Types include:

• Type 1 diabetes is when patient’s bodies produce little to no insulin. In this form, the body’s own immune system attacks itself, destroying the cells that are responsible for creating insulin. Although the cause is unknown, researchers have speculated that it may be caused by a combination of genetic and environmental factors.

• Type 2 diabetes is when the body is resistant to the insulin that is produced. This form of diabetes accounts for about 80 percent of all diabetes cases. It is closely linked to obesity and occurs more frequently in African Americans, Native Americans, Hispanics and Pacific Islanders.

• Gestational diabetes occurs in pregnant women when the body cannot produce enough insulin for both the mother and the developing fetus. Although it usually disappears after pregnancy, women who had experienced gestational diabetes have about a 20 to 50 percent chance of later developing type 2 diabetes.

Type 1 diabetics must take insulin for the rest of their lives or slip into a diabetic coma. Currently, insulin must be injected, but researchers are working on new delivery methods, such as insulin patches or inhalable insulin.

Type 2 diabetics may sometimes require insulin therapy. However, physicians also recommend weight loss and dietary changes to help regulate blood glucose levels. For more information on heart-healthy diabetic lifestyles, see Recipes for Diabetics and Exercise for Diabetics.

Diabetes

Diabetes Overview

Diabetes is a set of related diseases in which the body cannot regulate the amount of sugar (glucose) in the blood.

Glucose in the blood gives you energy—the kind you need when you walk briskly, run for a bus, ride your bike, take an aerobics class, and for your day to day chores.

• Glucose in the blood is produced by the liver from the foods you eat.
• In a healthy person, the blood glucose level is regulated by several hormones, one of which is insulin. Insulin is produced by the pancreas, a small organ near the stomach that also secretes important enzymes that help in the digestion of food.
• Insulin allows glucose to move from the blood into liver, muscle, and fat cells, where it is used for fuel.
• People with diabetes either don't produce enough insulin (type 1 diabetes) or cannot use insulin properly (type 2 diabetes), or both.
• In diabetes, glucose in the blood cannot move into cells, and stays in the blood. This not only harms the cells that need the glucose for fuel, but also harms certain organs and tissues exposed to the high glucose levels.

Type 1 diabetes: The body stops producing insulin or produces too little insulin to regulate blood glucose level.

• Type 1 diabetes comprises about 10% of total cases of diabetes in the United States.

• Type 1 diabetes is typically recognized in childhood or adolescence. It used to be known as juvenile-onset diabetes or insulin-dependent diabetes mellitus.

• Type 1 diabetes can occur in an older individual due to destruction of pancreas by alcohol, disease, or removal by surgery or progressive failure of pancreatic beta cells, which produce insulin.

• People with type 1 diabetes generally require daily insulin treatment to sustain life.

Type 2 diabetes: The pancreas secretes insulin, but the body is partially or completely unable to use the insulin. This is sometimes referred to as insulin resistance. The body tries to overcome this resistance by secreting more and more insulin. People with insulin resistance develop type 2 diabetes when they do not continue to secrete enough insulin to cope with the higher demands.

• At least 90% of patients with diabetes have type 2 diabetes.
• Type 2 diabetes is typically recognized in adulthood, usually after age 45 years. It used to be called adult-onset diabetes mellitus, or non–insulin-dependent diabetes mellitus. These names are no longer used because type 2 diabetes does occur in younger people, and some people with type 2 diabetes need to use insulin. Type 2 diabetes is usually controlled with diet, weight loss, exercise, and oral medications. More than half of all people with type 2 diabetes require insulin to control their blood sugar at some point in the course of their illness. Gestational diabetes is a form of diabetes that occurs during the second half of pregnancy. Although gestational diabetes typically goes away after delivery, women who have gestational diabetes are more likely than other women to develop type 2 diabetes later in life.

  Women with gestational diabetes are more likely to have large babies.

Metabolic syndrome (syndrome X) is a set of abnormalities in which insulin-resistant diabetes (type 2) is almost always present and includes hypertension, hyperlipidemia (increased serum lipids, predominant elevation of LDL, decrease in HDL, and elevated triglycerides), central obesity, and abnormalities in blood clotting and inflammatory responses. A high rate of cardiovascular disease is associated with the metabolic syndrome.

Pre-diabetes is a common condition related to diabetes. In people with pre-diabetes, the blood sugar level is higher than normal but not high enough to be considered diabetes.

• Pre-diabetes increases your risk of getting type 2 diabetes and of having heart disease or a stroke.
• Pre-diabetes can be reversed without insulin or medication by losing a modest amount of weight and increasing your physical activity. This can prevent, or at least delay, onset of type 2 diabetes.

• An international expert committee of the American Diabetes Association recently redefined the criteria for pre-diabetes, lowering the blood sugar level cut-off point for pre-diabetes. Approximately 20% more adults are now believed to have this condition and may develop diabetes within 10 years if they do not exercise or maintain a healthy weight.

  About 17 million Americans (6.2%) are believed to have diabetes. About one third of those do not know they have it.

• About 1 million new cases occur each year, and diabetes is the direct or indirect cause of at least 200,000 deaths each year.

• The incidence of diabetes is increasing rapidly. This increase is due to many factors, but the most significant are the increasing incidence of obesity and the prevalence of sedentary lifestyles.

  Complications of diabetes

  Both forms of diabetes ultimately lead to high blood sugar levels, a condition called hyperglycemia. Over a long period of time, hyperglycemia damages the retina of the eye, the kidneys, the nerves, and the blood vessels.

• Damage to the retina from diabetes (diabetic retinopathy) is a leading cause of blindness.

• Damage to the kidneys from diabetes (diabetic nephropathy) is a leading cause of kidney failure.

• Damage to the nerves from diabetes (diabetic neuropathy) is a leading cause of foot wounds and ulcers, which frequently lead to foot and leg amputations.

• Damage to the nerves in the autonomic nervous system can lead to paralysis of the stomach (gastroparesis), chronic diarrhea, and an inability to control heart rate and blood pressure with posture changes.

• Diabetes accelerates atherosclerosis, or the formation of fatty plaques inside the arteries, which can lead to blockages or a clot (thrombus), which can then lead to heart attack, stroke, and decreased circulation in the arms and legs (peripheral vascular disease).

• Diabetes predisposes people to high blood pressure and high cholesterol and triglyceride levels. These independently and together with hyperglycemia increase the risk of heart disease, kidney disease, and other blood vessel complications.

  In the short run, diabetes can contribute to a number of acute (short-lived) medical problems.

• Many infections are associated with diabetes, and infections are frequently more dangerous in someone with diabetes because the body's normal ability to fight infections is impaired. To compound the problem, infections may worsen glucose control, which further delays recovery from infection.

• Hypoglycemia, or low blood sugar, occurs from time to time in most people with diabetes. It results from taking too much diabetes medication or insulin (sometimes called "insulin reaction"), missing a meal, doing more exercise than usual, drinking too much alcohol, or taking certain medications for other conditions. It is very important to recognize hypoglycemia and be prepared to treat it at all times. Headache, feeling dizzy, poor concentration, tremors of hands, and sweating are common symptoms of hypoglycemia. You can faint or have a seizure if blood sugar level gets too low.
• Diabetic ketoacidosis is a serious condition in which uncontrolled hyperglycemia (usually due to complete lack of insulin or a relative deficiency of insulin) over time creates a buildup in the blood of acidic waste products called ketones. High levels of ketones can be very harmful. This typically happens to people with type 1 diabetes who do not have good blood glucose control. Diabetic ketoacidosis can be precipitated by infection, stress, trauma, missing medications like insulin, or medical emergencies like stroke and heart attack.

• Hyperosmolar hyperglycemic nonketotic syndrome is a serious condition in which the blood sugar level gets very high. The body tries to get rid of the excess blood sugar by eliminating it in the urine. This increases the amount of urine significantly and often leads to dehydration so severe that it can cause seizures, coma, even death. This syndrome typically occurs in people with type 2 diabetes who are not controlling their blood sugar or have become dehydrated or have stress, injury, stroke, or medications like steroids.

  Diabetes

  Diabetes Symptoms  Symptoms of type 1 diabetes are often dramatic and come on very suddenly.

• Type 1 diabetes is usually recognized in childhood or early adolescence, often in association with an illness (such as a virus) or injury.

• The extra stress can cause diabetic ketoacidosis.

• Symptoms of ketoacidosis include nausea and vomiting. Dehydration and often-serious disturbances in blood levels of potassium follow.

• Without treatment, ketoacidosis can lead to coma and death.

  Symptoms of type 2 diabetes are often subtle and may be attributed to aging or obesity.

• person may have type 2 diabetes for many years without knowing it.
• People with type 2 diabetes can develop hyperglycemic hyperosmolar nonketotic syndrome.
• Type 2 diabetes can be precipitated by steroids and stress.
• If not properly treated, type 2 diabetes can lead to complications like blindness, kidney failure, heart disease, and nerve damage. Common symptoms of both major types of diabetes
• Fatigue: In diabetes, the body is inefficient and sometimes unable to use glucose for fuel. The body switches over to metabolizing fat, partially or completely, as a fuel source. This process requires the body to use more energy. The end result is feeling fatigued or constantly tired.

• Unexplained weight loss: People with diabetes are unable to process many of the calories in the foods they eat. Thus, they may lose weight even though they eat an apparently appropriate or even excessive amount of food. Losing sugar and water in the urine and the accompanying dehydration also contributes to weight loss.

• Excessive thirst (polydipsia): A person with diabetes develops high blood sugar levels. The body tries to counteract this by sending a signal to the brain to dilute the blood, which translates into thirst. The body encourages more water consumption to dilute the high blood sugar back to normal levels and to compensate for the water lost by excessive urination.

• Excessive urination (polyuria): Another way the body tries to get rid of the extra sugar in the blood is to excrete it in the urine. This can also lead to dehydration because excreting the sugar carries a large amount of water out of the body along with it.

• Excessive eating (polyphagia): If the body is able, it will secrete more insulin in order to try to deal with the excessive blood sugar levels. Also the body is resistant to the action of insulin in type 2 diabetes. One of the functions of insulin is to stimulate hunger. Therefore, higher insulin levels lead to increased hunger and eating. Despite increased caloric intake, the person may gain very little weight and may even lose weight.

• Poor wound healing: High blood sugar levels prevent white blood cells, which are important in defending the body against bacteria and also in cleaning up dead tissue and cells, from functioning normally. When these cells don't function properly, wounds take much longer to heal and become infected more frequently. Also, long-standing diabetes is associated with thickening of blood vessels, which prevents good circulation and our body tissues from getting enough oxygen and other nutrients.

• Infections: Certain infection syndromes, such as frequent yeast infections of the genitals, skin infections, and frequent urinary tract infections, may result from suppression of the immune system by diabetes and by the presence of glucose in the tissues, which allows bacteria to grow well. They can also be an indicator of poor blood sugar control in a person known to have diabetes.

• Altered mental status: Agitation, unexplained irritability, inattention, extreme lethargy, or confusion can all be signs of very high blood sugar, ketoacidosis, or hyperosmolar hyperglycemia nonketotic syndrome or hypoglycemia (low sugar). Thus, any of these merit the immediate attention of a medical professional. Call your health care provider or 911.
• Blurry vision: Blurry vision is not specific for diabetes but is frequently present with high blood sugar levels.

• A predisposition to develop type 1 diabetes may run in families but much less so than for type 2.
• Environmental factors, such as certain types of viral infections, may also contribute.
• Type 1 diabetes is most common in people of non-Hispanic white persons of Northern European descent, followed by African Americans and Hispanic Americans. It is relatively rare in those of Asian descent.
• Type 1 diabetes is slightly more common in men than in women.

  Type 2 diabetes: Type 2 diabetes is believed to have a strong genetic link, meaning that it tends to run in families. Several genes are being studied that may be related to the cause of type 2 diabetes. Risk factors for developing type 2 diabetes include the following:

• High blood pressure
• High blood triglyceride (fat) levels
• Gestational diabetes or giving birth to a baby weighing more than 9 pounds 
• High-fat diet
• High alcohol intake
• Sedentary lifestyle
• Obesity or being overweight
• Ethnicity: Certain groups, such as African Americans, Native Americans, Hispanic Americans, and Japanese Americans, have a greater risk of developing type 2 diabetes than non-Hispanic whites.
• Aging: Increasing age is a significant risk factor for type 2 diabetes. Risk begins to rise significantly at about age 45 years, and rises considerably after age 65 years.

Diabetes Treatment 

|Self-Care at Home| If you have diabetes, you would be wise to make healthful lifestyle choices in diet, exercise, and other health habits. These will help to improve glycemic (blood sugar) control and prevent or minimize complications of diabetes.

Diet: A healthy diet is key to controlling blood sugar and preventing diabetes complications.

• If you are obese and have had difficulty losing weight on your own, talk to your health care provider. He or she can recommend a dietitian or a weight modification program to help you reach your goal.
• Eat a consistent, well-balanced diet that is high in fiber, low in saturated fat, and low in concentrated sweets.
• A consistent diet that includes roughly the same number of calories at about the same times of day helps your health care provider prescribe the correct dose of medication or insulin.
• It will also help to keep your blood sugar at a relatively even level and avoid excessively low or high blood sugars, which can be dangerous and even life threatening.

  Exercise: Regular exercise, in any form, can help reduce the risk of developing diabetes. Activity can also reduce the risk of developing complications of diabetes such as heart disease, stroke, kidney failure, blindness, and leg ulcers.

• As little as 20 minutes of walking 3 times a week has a proven beneficial effect. Any exercise is beneficial; no matter how light or how long, some  exercise is better than no exercise.
• If you have complications of diabetes (eye, kidney, or nerve problems), you may be limited both in type of exercise and amount of exercise you can safely do without worsening your condition. Consult with your health care provider before starting any exercise program.

  Alcohol use: Moderate or eliminate your consumption of alcohol. Try to have no more than 7 alcoholic drinks in a week and never more than 2-3 in an evening. One drink is considered 1.5 ounces of liquor, 6 ounces of wine, or 12 ounces of beer. Excessive alcohol use is a known risk factor for type 2 diabetes. Alcohol consumption can cause low blood sugar, high blood sugar, nerve pain called neuritis, and increase in triglycerides, which is a type of fat in our blood.

  Smoking: If you have diabetes, and you smoke cigarettes or use any other form of tobacco, you are raising your risks markedly for nearly all of the complications of diabetes. Smoking damages blood vessels and contributes to heart disease, stroke, and poor circulation in the limbs. If you need help quitting, talk to your health care provider.

  Self-monitored blood glucose: Check your blood sugar frequently, at least before meals and at bedtime, and record the results in a logbook.

• This log should also include your insulin or oral medication doses and times, when and what you ate, when and for how long you exercised, and any significant events of the day such as high or low blood sugar and how you treated the problem.
• Better equipment now available makes testing your blood sugar less painful and less complicated than ever. Your daily blood sugar diary is invaluable to your health care provider in seeing how you are responding to medications, diet, and exercise in the treatment of your diabetes.
• Medicare now pays for diabetic testing supplies, as do many private insurers and Medicaid. |Medical Treatment| The treatment of diabetes is highly individualized, depending on the type of diabetes, whether you have other active medical problems, whether you have complications of diabetes, and your age and general health at time of diagnosis.

• Your health care provider will set goals for lifestyle changes, blood sugar control, and treatment.
• Together, you will devise a plan to help you meet those goals. Education about diabetes and its treatment is essential in all types of diabetes.
• When you are first diagnosed with diabetes, your diabetes care team will spend a lot of time with you, teaching you about your condition, your treatment, and everything you need to know to care for yourself on a daily basis.
• Your diabetes care team includes your health care provider and his or her staff. It may include specialists in foot care, neurology, kidney diseases, and eye diseases. A professional dietitian and a diabetes educator also may be part of the team.

  Your care team will see you at appropriate intervals to monitor your progress with your goals. Type 1 diabetes

  Treatment of diabetes almost always involves the daily injection of insulin, usually a combination of short-acting insulin such as regular or Lispro or Aspart insulin and a longer acting insulin such as NPH, lente, glargine, or ultralente insulins.

• Insulin must be given as an injection. If taken by mouth, insulin would be destroyed in the stomach before it could get into the blood where it is needed.
• Most people with type 1 diabetes give these injections to themselves. Even if someone else usually gives you your injections, it is important that you know how to do it in case the other person is not available.
• A trained professional will show you how to store and inject the insulin. Usually this is a nurse who works with the health care provider or a diabetes educator.
• Insulin is usually given in 2 or 3 injections per day, generally around mealtimes. Dosage is individual and is tailored by your health care provider.
• It is very important to eat if you have taken insulin, as the insulin will lower your blood sugar regardless of whether you have eaten. If you take insulin without eating, you could have hypoglycemia. This is called an insulin reaction.
• There is an adjustment period while you learn how insulin affects you and how to time your mealtimes and exercise times with your insulin injections to keep your blood sugar as even as possible.
• Keeping accurate records of your blood sugars and insulin dosages is crucial in helping your health care provider take care of your diabetes.
• Eating a consistent, healthy diet appropriate for your size and weight is essential in controlling your blood sugar. Type 2 diabetes

  Depending on how elevated your blood sugar and glycosylated hemoglobin are at the time of your diagnosis, you may be given a chance to lower your blood sugar without medication.

• The best way to do this is to lose weight if you are obese and begin an exercise program.
• This will generally be tried for 3-6 months, and then your blood sugar and glycosylated hemoglobin will be rechecked. If they remain high, you will be started on an oral medication, usually a sulfonylurea or biguanide (Metformin), to help control your blood sugar.

• Even if you are on medication, it is still important to eat a healthy diet, lose weight if you are overweight, and engage in moderate physical activity as often as possible.
• Your health care provider will monitor your progress on medication very carefully at first. It is important to get just the right dose of the right medication to get your blood sugar in the recommended range with the fewest side effects.
• Your doctor may decide to combine two types of medications to get your blood sugar under control.
• Gradually, even people with type 2 diabetes may require insulin injections to control their blood sugar.
• It is becoming more common for people with type 2 diabetes to take a combination of oral medication and insulin injections to control blood sugar. |Medications|

  Many different types of medications are available to help lower blood sugar in type 2 diabetes. Each type works in a different way. It is very common to combine 2 or more types to get the best effect with fewest side effects.

• Sulfonylureas: These drugs stimulate your pancreas to make more insulin.
• Biguanides: These agents decrease the amount of glucose produced by your liver.
• Alpha-glucosidase inhibitors: These agents slow absorption of the starches you eat. This slows down glucose production.
• Thiazolidinediones: These agents increase your sensitivity to insulin.
• Meglitinides: These agents stimulated the pancreas to make more insulin.
• D-phenylalanine derivatives: These agents stimulate your pancreas to produce more insulin more quickly.

Study Describes Treatment Strategies for Pediatric Diabetes Complication Physicians treating ill children who are hyperglycemic and dehydrated should include hyperglycemic hyperosmolar syndrome (HHS) in their suspicions, according to a case report.

HHS, a life-threatening complication of type 2 diabetes, has increased more than tenfold in the U.S. pediatric population over the last decade. HHS is well described in the adult literature and has a 10%-50% mortality rate. The investigators noted that this is the first discussion of pediatric HHS treatment strategies.

"We believe that HHS will become more common in the pediatric population because of the recent epidemic of obesity in children," said lead author, Rebecca M. Carchman, MD, from the department of critical care at the University of North Carolina Hospital in Chapel Hill. "Obesity is a major risk factor for type 2 diabetes. HHS may be the first presentation of pediatric type 2 diabetes, as it was in our patients."

The authors of the case report described four obese adolescents with hyperglycemic hyperosmolar syndrome associated with type 2 diabetes. The patients were treated with isotonic fluid resuscitation and insulin. Two of the four patients died. The first presumably died due to hypovolemic shock and the second developed rhabdomyolysis and multisystem organ failure. None of the patients had cerebral edema. The report appeared in Pediatric Critical Care Medicine.

"Because of the high mortality rate and complication risk associated with HHS, it is essential that pediatricians, emergency physicians and pediatric intensivists are aware of the disease," said Carchman. "It is also important that they recognize the degree of dehydration in HHS patients and treat aggressively. The risk of cerebral edema associated with aggressive fluid resuscitation in HHS is unknown."

The typical presenting triad of HHS is severe hyperglycemia (blood glucose >600 mg/dL), hyperosmolality (>320 mosm/L) and a mild metabolic acidosis (pH >7.3) with no ketosis.

"Patients with HHS are extremely dehydrated - it is estimated that they have 15%-20% total body water loss," Carchman explained. "Most patients, however, do not present with the typical laboratory values, and may have metabolic acidosis and ketosis due to longstanding dehydration. Because of this, the diagnosis of HHS may be confused with diabetic ketoacidosis (DKA)."

Guidelines for treatment of pediatric DKA emphasize conservative fluid resuscitation in order to avoid cerebral edema. The researchers recommended that children with HHS should not be treated like those in DKA. HHS should be treated with rapid and aggressive fluid resuscitation because the risk of hypovolemic shock is greater than that of cerebral edema in this disease. Another complication of HHS is rhabdomyolysis, which should be suspected and treated to avoid renal failure.

The evidence for the initial treatment and management of pediatric HHS is limited to extrapolations from the adult literature and pediatric case reports. Nevertheless, the investigators believe that pediatric patients require more rapid fluid administration than in DKA because of the risk of hypovolemic shock associated with severe dehydration. The risk of cerebral edema in HHS is unknown.

"Pediatric patients with HHS have a high mortality rate and may experience multiple complications such as rhabdomyolysis and hypovolemic shock," the researchers concluded. "Treatment strategies to reduce mortality are unclear and warrant further investigation."

In an accompanying editorial, Dr. Sunit C. Singhi, MD, professor of pediatrics and head of the pediatric emergency and intensive care units at the Advanced Pediatrics Center, Postgraduate Institute of Medical Education and Research in Chandigarh, India, discussed the high mortality associated with HHS and the problems coupled with proper diagnosis and effective treatment.

"In adolescents with extreme obesity and [type 2 diabetes], life-threatening hyperglycemic hyperosmolar syndrome appears be on rise," he said. "Population-based data are needed to estimate the magnitude of the problem in view of increasing incidence of obesity and type 2 [diabetes] in younger age groups in certain ethnic groups. Prospective trials are needed to resolve controversy surrounding composition of the resuscitations and rehydration fluids and the rate of fluid infusion."

"Although this is a case study, practitioners need to pay close attention to presentation and treatment of HHS in the pediatric population," said PCCM editor Patrick M. Kochanek, MD, FCCM. "This syndrome looms large in the future. Trials should be performed to define treatment." This article was prepared by Biotech Week editors from staff and other reports. Copyright 2005, Biotech Week via NewsRx.com & NewsRx.net

15-FEB-2005

Study Examines How Diabetes May Develop in Overweight People

ST. LOUIS - Fat burning is touted as the key to weight loss, but it may also link obesity and diabetes, research from Washington University suggests.

Daniel P. Kelly, director of the Center for Cardiovascular Research at the university, and his colleagues were studying the heart when they made a discovery that could provide new understanding for how diabetes develops in overweight and obese people.

The results of their study appear Wednesday in the journal Cell Metabolism.

The researchers noted that when fat gets into the heart, the organ stops burning sugar for energy.

"There's this yin and yang between fat and sugars," Kelly said.

Normally, cells use a sugar called glucose for energy, but they may also use fatty acids as less efficient fuel sources. When cells stop burning sugar and switch exclusively to fat fuel, blood sugar levels rise and insulin stops working. Those are two hallmarks of diabetes.

Kelly and his colleagues discovered that a molecule known in short as PPAR-alpha (its full name is peroxisome proliferator-activated receptor-alpha) acts in muscle cells as a fuel-source switch. The switch is thrown when animals - mice in Kelly's research - and perhaps people take in more calories than they can use and become obese. Fat cells store the excess calories as fatty acids.

But "at some point the reservoir is full. You can only expand your fat tissue so much," Kelly said.

The body may begin storing fat in tissues, such as muscle and liver, where it doesn't belong, he said.

And when the fat spills over into muscle, PPAR-alpha gets going. The molecule helps muscle cells bring in and burn fatty acids, and shuts down sugar consumption.

"It's telling the muscles `don't listen to insulin anymore. We don't need to burn sugar,'" Kelly said.

The result is high blood sugar and insulin-insensitive cells. In other words, a step toward diabetes.

The scientists genetically engineered two different types of mice - one type that made excess PPAR-alpha in their muscles and another that lacked the molecule.

The researchers found that mice that over-produce PPAR-alpha become diabetic even though they are thin. That's because their muscle cells become fat-burning machines that ignore insulin and glucose.

Conversely, mice lacking PPAR-alpha were prone to growing heavy, but they seemed to be protected against getting diabetes.

That could mean that drugs to block the action of the molecule could prevent diabetes, Kelly suggested.

The results are a mixed blessing, said Sam Klein, director of the Center for Human Nutrition at Washington University. Klein was not involved in the research.

"In terms of obesity, this is a cure. In terms of diabetes, this is a cause," Klein said.

No one knows if the mechanism also works in people. The mice in the study still had active pancreas cells, so the research did not address the full picture of diabetes, Klein said.

But the study may offer some clues about one reason why 65 percent to 90 percent of diabetics are also overweight, Klein said. Not everyone who is obese will develop diabetes - about 15 percent of obese people are diabetic - but overweight and obesity are risk factors for the disease. It is rare for someone who is of normal weight to get Type 2 diabetes, the form once known as adult-onset diabetes, Klein said.

The new study contradicts some of the conclusions of earlier studies with mice and is likely to be "provocative," Klein said.

"It makes us more confused about what we thought we knew before," Klein said.

But in scientific circles, that's good news. Follow-up studies could help determine the steps that lead to diabetes in obese people and find ways to stop the disease from developing, he said.