Van's Health Foods

Zinc reduced lower respiratory infections

Zinc is an essential mineral for healthy development and immunity. In this study, 192 children who were low in zinc and other nutrients took 10 mg of zinc gluconate per day or a placebo for 60 days. Doctors followed the children for four months, keeping track of respiratory infections.

Compared to children in the placebo group, kids who took zinc were less than half as likely to have acute or severe lower respiratory infections. The children who took zinc also had more healthy days without infection, and recovered from infection far faster than kids who had taken the placebo.

Vitamin D reduced respiratory infection

Recent evidence has shown that vitamin D is important not only for developing bones, but also for strengthening immune systems. Because the body produces vitamin D from the sun, it is particularly important to maintain good levels in winter months. This study took place in a northern climate, where vitamin D deficiency is common in winter.

At the start of the study, all the 250 children who participated were very low in vitamin D. The children drank locally produced milk with or without 300 IU of added vitamin D per day. Over the course of the winter, parents of children in the vitamin D group reported about half the number of respiratory infections as parent of the kids in the placebo group.

In discussing their findings, doctors said the large benefit they saw was due to the very low levels of vitamin D at the start of the study, and suggest further study to determine the best level of vitamin D.

Reference: Clinical Nutrition; August, 2012, Electronic Prepublication

From the February 2013 newsletter

Nutrients helped reduce recurring URTI’s

Doctors said that getting vitamins and minerals in the right amounts can boost immunity and protect against upper respiratory tract infection (URTI). In this study, 192 people with recurrent URTI’s took a daily supplement containing vitamin C, vitamin D3, folic acid, and selenium, or a placebo. Researchers followed the two groups to measure the number, intensity, and course of URTI’s.

After 16 weeks, nearly half of those in the placebo group had missed work compared to 14 percent for the supplement group. Doctors also measured circulating levels of the four nutrients and found that vitamin C, folic acid and selenium increased in the supplement group, while vitamin D declined for both groups, but declined less in the supplement group. Those in the supplement group who began the study with insufficient vitamins C or D also had improved respiratory health.

Vitamin D lowers chances of viral infection

Because vitamin D levels decline in the fall and winter when there is less and weaker sunlight, people may catch cold more easily, doctors said. In the first phase of this two-part study, researchers measured vitamin D levels in three healthy groups: young people aged 20 to 30, middle-aged people 31-59, and older adults aged 60 to 86, and found circulating vitamin D levels decreased with age.

In the second phase of the study, using the same group of volunteers, doctors found that the special immune receptors designed to intercept and kill viruses were more likely to function normally as levels of vitamin D increased.

Reference: Journal of Leukocyte Biology; 2012, Vol. 91, No. 5, 829-38

From the October 2012 newsletter

Probiotics replenish good intestinal bacteria that antibiotics take away. Doctors say nearly one in three who take antibiotics to treat infection get diarrhea, which may cause them to stop taking the treatment early. In this large review, researchers analyzed 63 antibiotic-infection treatment studies including 11,811 people, who also took probiotics-most commonly Lactobacillus-with their antibiotic treatment. Compared to placebo, those who took probiotics along with antibiotics were 42 percent less likely to have diarrhea as a side effect. People got the benefit regardless of the type or dose of probiotics.

Reference: Journal of the American Medical Association; 2012, Vol. 307, No. 18, 1959-69

From the August 2012 newsletter