Vitamin D Levels Linked to Healthy Lung Function

Vitamin D may play a role in keeping our lungs healthy, with higher concentrations of vitamin D resulting in positive effects on lung function and health.

Low concentrations of vitamin D have been associated with a number of diseases. Research out of New Zealand indicates that serum concentrations of vitamin D may also influence pulmonary (lung) function.

In a study published in the journal Chest, original analysis was performed on data from 14,091 adult subjects (all participants in the U.S. National Health and Nutrition Examination Survey conducted between 1988 and 1994). Lung function was measured in two ways: by the volume of air that could be forcibly blown out in total (forced vital capacity, or FVC), and the volume blown out in one second (forced expiratory volume, or FEV1). Vitamin D was measured using serum 25-hydroxyvitamin D, a standard indicator of vitamin D levels.

After adjusting for age, gender, height, body mass index, ethnicity, and smoking history, the difference in lung function between the groups with the highest and lowest vitamin D intake was substantial in both the FVC and FEV1 tests (172 mL and 126 mL respectively, p <0.0001). Further adjustment for physical activity, vitamin D supplementation, milk intake, and serum antioxidant status revealed additional strong correlation between the highest and lowest intake groups (142 mL (FVC) and 106 mL (FEV1), p < 0.0001).

Although further studies are necessary to determine whether vitamin D supplementation may be beneficial in cases of chronic respiratory disease, this study has shown that vitamin D may have a positive influence on pulmonary health, with greater levels of vitamin D associated with more positive benefits.

Chest 2005 Dec;128(6):3792-8

Regular Exercise Reduces Risk of the Common Cold

New research shows a strong correlation between regular aerobic exercise and reduced risk of upper respiratory tract infections.


Upper Respiratory Tract Infections (URTI) can be caused by more than 200 different viruses, and it is estimated that the U.S. population suffers more than one billion colds a year (2-4 per average adult, 6-10 per average child). A number of lifestyle factors contribute to URTI risk, including poor nutrient status, lack of sleep, and stress. A new paper published in the British Journal of Sports Medicine adds exercise habits to the list of lifestyle factors affecting URTI risk.

1,023 subjects between 18 and 85 years of age were recruited for this study, with 1,002 individuals completing all study requirements. Subjects were selected from multiple BMI groups (roughly one-third were of normal weight, one-third were overweight, and one-third were obese) to ensure adequate representation. A comprehensive validated survey on lifestyle, diet, activity levels, stress, and URTI incidence and severity was completed by each study participant.

After controlling for potential cofounders, total days with URTI symptoms were 43-46% lower in the highest third of aerobic activity when compared to the lowest third, while URTI severity was reduced 32-41% for the high group. Low stress levels, high exercise frequency (≥5 days/week), and high fruit intake (≥3 servings/day) also correlated with reduced URTI incidence.

The exact mechanism by which aerobic exercise reduces URTI risk is still uncertain, although it appears to be a combination of factors, including transient increases of certain immune cell types, a reduction of stress hormones, and specialized benefits to key organs (particularly the lungs, which serve as a primary barrier against URTIs).

Nieman DC, Henson DA, Austin MD, Sha W. Upper respiratory tract infection is reduced in physically fit and active adults. 2010. Br J Sports Med, ePub ahead of print. doi:10.1136/bjsm.2010.077875