Diabetes & Nutrition Part II: Vitamins & Minerals

Some Nutrients Can Be a Problem in Diabetes

Twenty-four million Americans - nearly 25% of those 60 and older - currently suffer from diabetes according to the Centers for Disease Control. Fifty seven million more have pre-diabetes which often leads to the full-blown disease. Meeting vitamin and mineral needs is important for everyone, but for those with diabetes - or those at risk for this condition - getting enough of certain nutrients can be a problem. Some nutrients may be compromised in diabetics due to poor intake, faster excretion, or greater need.

Vitamin D and B-Vitamin Shortfalls

Vitamin D is important for healthy bones and for its anti-inflammatory activity, and low levels are common in adults with type 2 diabetes. Up to 75% of young people with type 1 may also be deficient in vitamin D according to new evidence (1). A recent review of studies suggests that for lowering the risk of type 2 in women, 800 IU of this vitamin is more effective than 400 IU (2).

People with type 1 & 2 diabetes excrete more thiamin (vitamin B1,) and have low blood levels compared to those free of the disease. Researchers report that blood concentrations of thiamine were decreased by about 75% in type 1 & 2 diabetics vs. healthy controls (3). Thiamin plays a role in the body's metabolism of glucose, and low levels have been found to increase the risk of kidney, nerve and eye complications in animals.

Low B6 has been observed in those with type 1 and 2, and B6 levels generally decline with age. Older people are also at risk for sub-optimal levels of B12, a vitamin critical to proper nerve function. Diabetics have a greater risk for cataract, and riboflavin (B2) and thiamine have been linked to decreased risk. In an AREDS analysis, long-term multi use lowered cataract risk by 16-25%. Many of the participants in this trial were diabetic.

Antioxidants Help Combat Oxidative Stress

Diabetics have higher levels of oxidative stress - an imbalance between the production of damaging oxygen compounds and the body's ability to neutralize them. Oxidative stress contributes to long-term complications in diabetes such as vision (retinopathy), kidney (nephropathy), nerve (neuropathy) and heart disease.

Antioxidants such as vitamins C and E help counter oxidative stress. Vitamin C appears to be particularly important. Higher blood levels of this vitamin, for example, were linked to a 62% lower risk of developing diabetes in 21,000 people followed for 12 years (4). Additionally, in a large-scale government survey, long-term use of supplemental C, E and/or a multinutrient, lowered the risk of developing retinopathy (5).

Meaningful Minerals Can Be Missing

Magnesium, which is involved in maintaining artery health and sensitivity to insulin, is often low in diabetics with poor blood sugar control. If you are at risk for diabetes, note that research strongly suggests that better dietary magnesium intake lowers the risk of developing hypertension, metabolic syndrome and diabetes itself (6).

Zinc and chromium are minerals important for proper insulin function, and both have antioxidant activity. Urinary loss of zinc can be higher in type 1 and 2 diabetics (7). Evidence, too, suggests that chromium supports healthier blood glucose levels in people who are low in this trace mineral and have impaired glucose tolerance (8).

References

1. Svoren BM, et al. Significant vitamin D deficiency in youth with type 1 diabetes. J of Pediatrics 154:132-34 2009.
   
2. Pittas AG, et al. The role of vitamin D and calcium in type 2 diabetes. A systematic review and meta-analysis. J Clin Endocrinol Metab 92:2017-29, 2007
   
3. hornally PF, et al. High prevalence of low plasma thiamine concentration in diabetes linked to a marker of vascular disease. Diabetologia 50:2164-70, 2007
   
4. Harding AH, et al. Plasma vitamin C level, fruit and vegetable consumption and the risk of new-onset type 2 diabetes mellitus-The European Prospective Investigation of Cancer-Norfolk Prospective Study. Arch Int Med 168:1493-99, 2008.
   
5. Millen AE, et al. Relations of serum ascorbic acid and alpha-tocopherol to diabetic retinopathy in the 3rd National Health and Nutrition Exam Survey. Am J Epidemiol 158:225-33, 2003.
   
6. Larsson A, et al. Magnesium intake and risk of type-2 diabetes: a meta-analysis J Int Med [ePub] 2007
   
7. Ross CA. In Modern Nutrition in Health and Disease. Shils ME et al Eds; Lippincott Williams & Wilkins Pub, 10th Ed, 2006.
   
8. Balk EM, et al. Effect of chromium supplementation on glucose metabolism and lipids: a systematic review of randomized controlled trials. Diabetes Care 30:2154-63, 2007.