According to a new research, higher levels of maternal vitamin D during pregnancy have been linked to better muscle development in children.
The study on 678 children, published in Endocrine Research, showed vitamin D levels in the womb were linked to grip strength at the age of four.
The research team at the University of Southampton in UK says the muscle boost could persist throughout life.
Trials are taking place to see how effective pregnancy supplements are.
Most vitamin D is made by the skin when exposed to sunlight and supplements are offered during pregnancy.
Higher levels of maternal vitamin D during pregnancy have been linked to better muscle development in children
Some doctors have raised concerns about vitamin D deficiency as people become more “sun aware” and have linked it with a range of health problems.
The team at the University of Southampton investigated the impact of the vitamin in pregnancy.
Blood samples were taken 34 weeks into the pregnancy and the vitamin D levels were compared with how tightly their children could squeeze a device in their hand at the age of 4.
The results showed that women with high levels of vitamin D in the late stages of pregnancy were more likely to have children with greater muscle strength.
The group in Southampton is now conducting a trial in which 1,200 expectant mothers are given higher doses of vitamin D supplements to assess the impact on both bone and muscle strength.
French researchers have cast doubt on the value of vitamin D supplements to protect against diseases such as cancers, diabetes and dementia.
Scientists writing in The Lancet Diabetes and Endocrinology suggest low vitamin D levels do not cause ill health, although they did not look at bone diseases.
More clinical trials on non-skeletal diseases are needed, they say.
Vitamin D supplements are recommended for certain groups.
French researchers have cast doubt on the value of vitamin D supplements to protect against diseases such as cancers, diabetes and dementia
Recent evidence has shown it may also have a role to play in preventing non-bone-related diseases such as Parkinson’s, dementia, cancers and inflammatory diseases.
Prof. Philippe Autier, from the International Prevention Research Institute in Lyon, carried out a review of data from 290 prospective observational studies and 172 randomized trials looking at the effects of vitamin D levels on health outcomes, excluding bone health, up to December 2012.
A large number of the observational studies suggested that there were benefits from high vitamin D – that it could reduce the risk of cardiovascular events by up to 58%, diabetes by up to 38% and colorectal cancer by up to 33%.
But the results of the clinical trials – where participants were given vitamin D supplements – found no reduction in risk, even in people who started out with low vitamin D levels.
And a further analysis of recent randomized trials found no positive effect of vitamin D supplements on diseases occurring.
Prof. Philippe Autier said: “What this discrepancy suggests is that decreases in vitamin D levels are a marker of deteriorating health.
“Ageing and inflammatory processes involved in disease occurrence… reduce vitamin D concentrations, which would explain why vitamin D deficiency is reported in a wide range of disorders.”
According to a new study, healthy adults do not need to take vitamin D supplements.
The study published in The Lancet found the subjects had no beneficial effect on bone density, a sign of osteoporosis.
Experts say many other factors could be at play and people should not stop taking supplements.
University of Auckland researchers analyzed 23 studies involving more than 4,000 healthy people.
The New Zealand research team conducted a meta-analysis of all randomized trials examining the effects of vitamin D supplementation on bone mineral density in healthy adults up to July 2012.
The supplements were taken for an average of two years by the study participants.
Healthy adults do not need to take vitamin D supplements
Bone mineral density is a measure of bone strength and measures the amount of bone mineral present at different sites in the body. It is often seen as an indicator for the risk of osteoporosis, which can lead to an increased risk of fracture.
The trials took place in a number of different countries including the UK, the US, Australia, Holland, Finland and Norway.
Although the results did not identify any benefits for people who took vitamin D, they did find a small but statistically significant increase in bone density at the neck of the femur near the hip joint.
According to the authors, this effect is unlikely to be clinically significant.
Prof. Ian Reid, lead study author, from the University of Auckland, said the findings showed that healthy adults did not need to take vitamin D supplements.
“Our data suggest that the targeting of low-dose vitamin D supplements only to individuals who are likely to be deficient could free up substantial resources that could be better used elsewhere in healthcare.”
Writing about the study in The Lancet, Clifford J. Rosen from the Maine Medical Research Institute agrees that science’s understanding of vitamin D supports the findings for healthy adults, but not for everyone.
“Supplementation to prevent osteoporosis in healthy adults is not warranted. However, maintenance of vitamin D stores in the elderly combined with sufficient dietary calcium intake remains an effective approach for prevention of hip fractures.”
The Department of Health currently recommends that a daily supplement of vitamin D of 10 micrograms (0.01 mg) should be taken by pregnant and breastfeeding women and people over 65, while babies aged six months to five years should take vitamin drops containing 7 to 8.5 micrograms (0.007-0.0085 mg) per day.