Addressing Diabetes with Nutritional Ingredients

by Jay Udani, M.D.

As the population ages, it also expandsat the waistline. The global obesity epidemic is the prelude to the coming diabetes epidemic, and people worldwide will be looking for natural health products to assist in the management of this condition.

The list of natural ingredient purported to manage blood sugar is long and full of opportunity. These ingredients have been used traditionally for prevention and as an adjunct to management of impaired glucose tolerance. They can also be used in combination with allopathic therapies in synergistic ways.

The path from obesity to diabetes is not a straight line. Several mechanisms are involved, and natural health products have the ability to influence them all. Prevention and treatment strategies include reversing the decline in adiponectin, increasing insulin sensitivity, reducing inflammation, reducing oxidative stress, enhancing glycemic control and reducing weight.

First, consider the issue of raising adiponectin levels. Ingredients known as PPAR-gamma agonists have been shown as a class to increase adiponectin levels. They have a synergistic effect with insulin, and reduce inflammation in the liver, adipose and vascular tissues (Gervois et al. 2004; Hseuh et al. 2003). Of the products with known PPAR-gamma activity, none have been demonstrated to show significant increases in adiponectin in humans. These products, including bitter melon, mulberry leaf, Korean red ginseng, banaba, Punica granatum and turmeric, show promise, but further study is necessary before they can be recommended specifically for treatment of low adiponectin.

Next, address increasing sensitivity to insulin, the primary hormone of blood sugar control. Ingredients that stimulate the production of insulin or mimic its effects can be effective in the regulation of blood sugar. A partial list of these ingredients includes bitter melon (Momordica charantia), Gymnema sylvestre, cinnamon and green tea. Bitter melon contains an insulin-like peptide called p-insulin (for plant insulin), which is structurally similar to mammal insulin. Human studies on bitter melon are encouraging, but have been uncontrolled and have used very high doses (up to 57 g/d). Gymnema sylvestre has been shown to increase insulin secretion, and may temporarily dull the ability to taste sweets, which may reduce sugar intake (Sivastava et al. 1993). Cinnamon studies have shown improvements in glucose and insulin modulation, but when five of the highest quality studies were combined for a meta-analysis, the benefits did not hold up (Baker et al. 2007). Green tea has been shown to increase insulin sensitivity by 13 percent in healthy volunteers (Venables et al. 2008) and reduce HbA1c compared with placebo (Fukino et al. 2008).

Another option is to reduce glucose absorption. Fenugreek (Trigonella foenum-graecum) is a soluble fiber, and has been shown to slow gastric emptying and thus may delay absorption of glucose from the gut (Sharma et al. 1990). A proprietary extract (Phase 2, from Pharmachem Laboratories) of the white kidney bean (Phaseolus vulgaris) has been shown to slow the rate of digestion of complex carbohydrates by competitively inhibiting alpha-amylase inhibition (Udani et al. 2007).

We can also consider mineral co-factors and additional antioxidants. The hyperglycemia of diabetes causes damage to the kidneys, and they become less effective at retaining certain minerals during the filtering process. As the excretion of these minerals increases, repletion back to homeostatic levels becomes more important in the overall regulation of blood sugar, causing a vicious cycle of increased damage, increased mineral loss and further damage. Mineral cofactors known to improve glucose management in diabetic subjects include chromium and magnesium. Selenium was previously thought to be helpful in diabetes management; however, some recent studies using selenium for the treatment of dermatologic disorders found supplementation with 200 mcg/d of selenium significantly increased the risk of becoming diabetic. More studies are ongoing, but the risk benefit ratio must always be considered when making supplementation recommendations.

Chronically elevated blood glucose levels can contribute to oxidative damage resulting in increased circulating free radicals. Vitamin E, beta-carotene and alpha-lipoic acid (ALA) have been shown to influence insulin and the consequences of diabetes, including peripheral neuropathy, presumably by reversing the levels of free radicals and their damage to target nerves and organs.

Finally, as inflammation appears to be both a cause and consequence of diabetes, reducing the levels of inflammation is a priority in the treatment of the disorder. Well known anti-inflammatories include fish oil (omega-3 fatty acids), cats claw, bromelain, ginger, boswellia, quercetin, evening primrose oil (EPO), borage oil, prickly pear cactus and turmeric.

These ingredients should be considered as pieces of a puzzle. When combined together in the right way, they can be valuable parts of a treatment strategy that preserves health, function and quality of life for millions of people around the world. Knowledge of their mechanism and activity provides the ability to use them safely and effectively either by themselves or in combination with standard medical care.

Jay Udani, M.D., is an assistant clinical professor at the UCLA School of Medicine and the CEO of Medicus Research LLC , a contract research organization (CRO) for the natural health products industries.