Latest Research on Diabetes & Nutrition

Diabetes: Once Rare, Now a Major Concern

According to an exhibition on diabetes and endocrinology at the Royal College of Physicians of Edinburgh, the first reference to diabetes in the literature dates back to 1550 BC when “the passing of too much urine” was mentioned in an Egyptian manuscript. Considerably later, in the 1st century AD, the Greek physician Aretaeus wrote the first complete clinical description of the disease. Noting the prominent symptom of excessive urination, Aretaeus coined the term diabetes, from the Greek meaning ‘siphon’ (1).

Once described as ‘rare’ by the ancient Egyptians, diabetes is now a major global health concern with over 220 million affected worldwide. Diet and exercise are key to preventing type-2 as well to help avoid complications in those who have the disease. Various issues of the Staying Healthy newsletter have reported on the impact of physical activity, the benefits of countering oxidative stress, and the consumption of low-glycemic carbohydrates to help control blood sugar levels. This issue highlights some intriguing new research on dietary strategies that could prove helpful in combating the condition. An important drug-nutrient interaction is also discussed.

Omega-3’s May Fight Insulin Resistance

Increased intake of omega-3 fatty acids was recently reported to improve biomarkers of insulin resistance2. Insulin resistance, or inefficient use of insulin by cells, can be a forerunner of type-2 diabetes. In this study of 167 men and women with altered blood lipid profiles, volunteers took either 1 gram softgels containing concentrated EPA and DHA or placebo 3 times daily for 6 months. Those taking the omega-3 had improved levels of HDL, triglycerides, and adiponectin – a protein made by fat cells. This protein helps regulate fat and glucose metabolism, and influences the body's response to insulin. Markers of insulin resistance also improved after administration of a high fat test dose.

Calorie Restriction Reduces Fat Deposits

Obesity can cause insulin resistance. That’s why weight loss is so important for people at risk for, or with, type-2. Research has also shown that excess calories can be stored as fat in the pancreas and liver, where it interferes with insulin production. This may increase the risk of developing type-2 in some people.

In a pilot study3, investigators at the University of Newcastle, gave a very low calorie diet (600 calories daily) for 2 months to 11 patients who had developed type-2 later in life. They were matched to a non-diabetic control group and monitored to measure the production of insulin and fat content of the pancreas and liver.

Scans showed that fat levels in the pancreas returned to normal. In fact, the diet appeared to reverse the symptoms of diabetes, with 64% of the participants remaining diabetes free for 3 months after the trial ended. These remarkable findings need to be tested in larger trials. Extremely low-cal diets should only be undertaken under close medical supervision.

Metformin and Vitamin B12 Depletion

There’s been increasing concern over the risk of vitamin B12 deficiency in people taking the common diabetes medication metformin4 (e.g. Glucophage). According to some studies, 10-30% of people taking this drug show evidence of decreased B12 absorption. If you’ve been taking the drug for several years or you take a high dose, it’s worth asking your health care provider to check your B12 levels. Checking blood levels of B12 should always be done with signs of B12 deficiency, especially those related to nerve problems such as numbness, pain or tingling in the hands or feet.

References

1. Graphic and exhibition information attributed to NutraIngredients, June 6, 2011, and Royal College of Physicians, www.rcpe.ac.uk
2. Derosa G, et al. Effects of n-3 PUFA on insulin resistance after an oral fat load. Eur J of Lipid Sci Tech, Epub ahead of print, June, 2011.
3. Lim EL, et al. Reversal of type-2 diabetes: normalization of beta cell function in association with decreased pancreas and liver triacylglycerol. Diabetologia 54:2506-14, 2011.
4. Kos E, et al. The effect of metformin therapy on vitamin D and B12 levels in patients with Diabetes Mellitus Type 2. Endocr Pract. Epub ahead of print, September, 2011.