Zinc supplements decrease incidence of infections in the elderly

Elderly adults are increasingly susceptible to infections, oxidative stress and immune dysfunction. According to new research, supplementing with zinc for one year decreased the incidence of infections and lowered markers of oxidative stress in a group of adults aged 55-87 years.

Adults over the age of 55 years are more susceptible to infections, immune dysfunction, increased oxidative stress, and zinc deficiency. Since zinc has anti-inflammatory and antioxidant properties, new research sought to determine the effect of zinc on the incidence of total infections in the elderly. Researchers also tested the effect of zinc on markers of oxidative stress.

A randomized, double-blind, placebo-controlled trial of zinc supplementation was conducted in 50 healthy subjects of both sexes aged 55-87 years. The zinc-supplemented group received 45 mg of zinc orally for 12 months. Incidence of infections during the supplementation period was documented. Plasma zinc concentrations and markers of oxidative stress were measured at the beginning and after supplementation.

After zinc supplementation, the incidence of infections was significantly lower, plasma zinc was significantly higher, and generation of oxidative stress markers was significantly lower in the zinc-supplemented than in the placebo group.

American Journal of Clinical Nutrition, Vol. 85, No. 3, 837- 844, March 2007

Supplemental vitamin D and calcium reduces risk of diabetes

The incidence of type-2 diabetes is lower among women who get adequate calcium and supplement with vitamin D. Researchers used data from the Nurses Health Study, which includes over 83,000 women, to study the relationship of calcium and vitamin D intake to type-2 diabetes.

After 20 years of follow-up, it was concluded that a combined daily intake of over 1,200 mg of calcium and more than 800 IU of vitamin D was associated with a 33 percent lower risk of type-2 diabetes. Interestingly, dietary vitamin D intake did not appear to provide any statistically significant benefit. But the women who supplemented with at least 400 IU of vitamin D had a 13% lower risk of diabetes when compared to those who took less than 100 IU per day. Both dietary and supplemental calcium resulted in decreased risk of type-2 diabetes, and those with overall intakes above 1,200 mg had a 21% lower risk than those who got less than 600 mg per day.

Elevated intakes of calcium and vitamin D, especially from supplements, are significantly associated with lower incidence of type-2 diabetes.

Diabetes Care 29:650-656, 2006

Calcium and vitamin D enhance heart health benefits of weight loss

Weight loss and reduced waist circumference are related to an improvement in heart health and factors related to metabolic syndrome. According to a new study, supplementing with calcium and vitamin D during weight loss enhances heart health benefits in women with typically low calcium intake.

Recent research has shown that overweight individuals with low calcium and dairy consumption are at increased risk of developing metabolic syndrome. The findings suggest that adequate calcium intake could create a healthier metabolic profile similar to a balanced diet and regular exercise.

In a new study, researchers investigated this issue by testing cardiovascular benefits of long-term calcium supplementation in women with usual low calcium intake. Healthy, overweight or obese women with a daily calcium intake of less than 800 mg/day were randomly assigned to 1 of 2 groups: the group consuming 2 tablets/day of a calcium + vitamin D supplement (600 mg elemental calcium and 200 IU vitamin D/tablet) or the group consuming placebo. Both groups completed a 15-week reduced calorie weight-loss program.

Significant decreases in LDL cholesterol levels, as well as the ratios of Total to LDL and LDL to HDL were seen the calcium +D group. These changes were independent of the changes due to fat loss and reduced waist circumference. A tendency for more beneficial changes in HDL cholesterol, triglycerides, and total cholesterol was also observed in the calcium +D group.

This was the first study to show that consumption of calcium +D during weight-loss enhances the beneficial effect of body weight loss on cardiovascular risk factors in overweight women with typically low calcium intake.

American Journal of Clinical Nutrition, Vol. 85, No. 1, 54-59, January 2007