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
