Researchers and clinicians are observing more cases of blood sugar problems among HIV+ people, particularly those on protease inhibitors (PIs). Researchers are working to discover why, among the many people on HIV medicines, only some have experienced blood sugar problems. Meanwhile, those with high blood sugar levels are looking for ways to curb the problem.

Diabetes is the condition in which sugar (glucose) has a hard time moving from blood into the cells where it is used for fuel. Insulin, a hormone, tells molecules to transport sugar into the cell.

Something in HIV disease metabolism, maybe related to PIs, seems to either make insulin less active, or make cells unable to respond well to its message ("insulin resistance"). This leaves sugar circulating in the blood, causing blood levels to be high. Left untreated, this can cause numerous health problems.

Diabetes is diagnosed by blood glucose (sugar) tests: a fasting level higher than 140 mg/dL is called "impaired glucose tolerance," and diabetes is diagnosed when the blood glucose level is consistently >140. Common symptoms include thirst, excessive urination, and weight loss.

When reading about diabetes and HIV disease, the numbers can be confusing; some studies talk about diabetes (constant high sugar), some about impaired glucose tolerance (random high sugar), and others about insulin resistance (impaired message system). Actual incidence of diabetes is low among people with HIV, at 3.7-9%; impaired glucose tolerance can be more common, at 23%; and insulin resistance seems to be highest, at 28-35%. By comparison, 20-25% of non-diabetic, HIV negative adults may be insulin resistant. The rate of diabetes in HIV+ women not on PIs is 1.9% and 1.4% for those receiving no treatment. An HIV-negative group of women in the same age category had a 0.9% rate of diabetes [figures taken from abstracts at the 6th Conference on Retroviruses, 1999].

One theory about the cause of diabetes involves the abnormally slow clearing of free fatty acids (FFAs), which are small fat molecules in the bloodstream. When levels of FFAs are high, cells get the message not to make so much glycogen (the storage form of glucose); thus the clearing mechanism for blood glucose is slowed down. Any number of events can cause higher levels of FFAs; fatty meals and obesity are known players, and perhaps Pls.

Nutritional deficiencies may contribute to trouble with insulin messaging. Essential fatty acid (omega-3 and -6) deficiencies may result in higher blood levels of FFAs and triglycerides JGs), and high TGs often accompany insulin resistance. Sadly, no studies have yet reported the status of essential fatty acid levels in people with HIV/AIDS, and the effects of Pls on essential fatty acid levels are unknown. Some people take fish oils (omega-3 fats) to lower TGs [see NFHL; 3(2)]. Also, low levels of magnesium and chromium accompany poor insulin function [J Nutr 1993; 123(4): 626-33]. Italian researchers Paolisso and Barbagallo theorize that low levels of magnesium inside cells are responsible for the whole complex of high blood pressure, diabetes, and heart disease in HIV-negative people [Am J Hypertens 1997;10(3):346-55].

Nutritionists also look at the role of antioxidants in insulin resistance. Alpha-lipoic acid works with vitamin E as an antioxidant in the liver. In European studies, supplements of alpha-lipoic acid lower blood sugar levels by improving insulin action and glycogen synthesis [Exp Clin Endocrinol Diabetes 1996; 104(3): 284-288]. Supplements like N-acetyl cysteine (NAC), vitamin C, and selenium support the antioxidant glutathione, and glutathione is crucial to insulin action.

Finally, insulin performance in the body can be a function of the blend of fats, starches, sugars, and protein in the diet. Meals that include high-fibre instead of low fibre carbohydrates seem to improve glucose tolerance. Some scientists worry that a high carbohydrate diet raises TG levels too much, especially when based on grain products made from refined instead of whole grain flours (i.e. whole wheat). In the right balance, use of oils like olive/canola/fish oil in place of animal and other saturated fats, can improve fatty acid levels in the blood.