Vitamin D deficiency (VDD) has been reported in very high rates in the U.S. population.
It has been implicated in various diseases such as:
- high blood pressure
- cardiovascular disease
- food allergy
The National Health and Nutrition examination survey (NHANES) in 2005-2006 was a cross-sectional nationwide survey in the U.S.
An allergy questionnaire inquired about self-reported allergic diseases including allergic rhinitis, allergies, and atopic dermatitis. Data were collected using the question, “Has the doctor or other health professional ever told you that you have allergies?“
The laboratory parameter of vitamin D level lower than 10 ng/mL was used to define severe vitamin D deficiency (VDD). The sample consisted of 5,000 people.
Vitamin D deficiency (VDD) was positively correlated with prevalence of allergies. There was also a correlation with rashes, sneezing, and sinus infections with low vitamin D.
Editor's comment: It all sounds plausible but we need confirmation from randomized controlled trials, which are currently underway. Until their results confirm that vitamin D deficiency plays a role in allergic disease, and supplementation is beneficial, all discussions on the topic are inconclusive.
Vitamin D deficiency as a risk factor for allergic disorders and immune mechanisms. Frieri M, Valluri A. Allergy Asthma Proc. 2011 Nov-Dec;32(6):438-44.
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