Increased oxidative stress is a major risk factor for the chronic complications of diabetes. People with diabetes typically have elevated levels of free radicals and oxidative compounds. These highly reactive compounds bind to and destroy cellular compounds. They also greatly increase the inflammatory process through the formation of inflammatory mediators like C-reactive protein.
One of the critical goals in diabetes prevention and treatment is to flood the body with a high level of antioxidants to counteract the negative effects of free radicals and oxidative compounds. Two critical antioxidants for diabetics are alpha-lipoic acid and flavonoid-rich extracts.
Grapeseed Extract in Diabetes
There are numerous beneficial effects of proanthocyanidin-rich flavonoids, such as grapeseed and pine bark (Pycnogenol) extracts, in battling the complications of diabetes. Proanthocyanidin flavonoids:
- Are more potent and effective against a broader range of oxidants than the traditional antioxidant nutrients vitamins C and E, beta-carotene, selenium and zinc
- Increase intracellular vitamin C levels and preserve important antioxidants like gluthathione
- Protect against damage to arteries and other blood vessels
- Decrease the leakiness and breakage of small blood vessels, which prevents easy bruising and promotes wound healing
One of the major complications of diabetes is an increased risk for heart attacks and stroke. In a very detailed four-week, double-blind study, grapeseed extract (600 mg a day) was compared to a placebo in 32 patients with type 2 diabetes. Results showed impressive reductions in markers for inflammation and oxidative stress. For example, whole blood glutathione levels were 3,595 mmol per liter in the grapeseed extract group, compared to 2,359 mmol per liter in the placebo group. The level of C-reactive protein was 2.2 mg per liter in the grapeseed group and 3.2 mg per liter in the placebo group. Achieving these reductions within one month is significant.
Kar P, Laight D, Rooprai HK, Shaw KM, Cummings M. Effects of grape seed extract in Type 2 diabetic subjects at high cardiovascular risk: a double blind randomized placebo controlled trial examining metabolic markers, vascular tone, inflammation, oxidative stress and insulin sensitivity. Diabet Med. 2009 May;26(5):526-31.