(Medical Xpress)—Taking vitamin D tablets cannot ward off heart attacks or stroke according to a new study from researchers at the University of East Anglia (UEA) published in the American Journal of Clinical Nutrition.
Recent studies have shown a link between low vitamin D levels and an increasing number of conditions including MS, diabetes, schizophrenia and asthma.
Previous research found that people with low vitamin D have are more likely to have cardiovascular disease. This new research reveals that taking vitamin D supplements does not reduce the risk of cardiovascular disease, however there is a chance that it could protect against heart failure in older people.
The research team looked at a trial involving more than 5,000 people aged over 60. While some were given a vitamin D supplement, others were given a placebo for up to five years. Cardiovascular events and mortality were assessed.
They also combined data from 21 other randomized trials involving more than 13,000 people which focused on vitamin D intake and cardiovascular outcomes.
Lead researcher Dr John Ford from UEA's Norwich Medical School said: "Vitamin D is both a hormone and a nutrient in that it can be both made in the body when it is exposed to sunlight and obtained from the foods we eat.
"It is known to have multiple and complex functions and there has been a lot of interest in the possibility that a lack of vitamin D might predispose a person to higher rates of heart disease and stroke. Several observational studies have provided evidence that cardiovascular patients tend to have lower circulating concentrations of vitamin D but we have shown that this is not a causal relationship. Instead vitamin D levels may be a marker for other risk factors, such as a sedentary lifestyle.
"There was however some evidence which suggested that the risk of dying from cardiac failure was lower among those taking a vitamin D supplement. There needs to be further research into whether a supplement could be beneficial."
The study was led by researchers from the University of East Anglia in collaboration with the University of Aberdeen, the University of Dundee and the University of Auckland in New Zealand.
More information: "Cardiovascular disease and vitamin D supplementation: trial analysis, systematic review, and meta-analysis." John A Ford, Graeme S MacLennan, Alison Avenell, Mark Bolland, Andrew Grey, Miles Witham, for the RECORD. Trial Group Am J Clin Nutr September 2014 doi: ajcn.082602 ajcn.113.082602v1.