Researchers from the universities of Surrey and Bristol examined data gathered from over 7,000 mother-child pairs in Children of the 90s. They discovered that pregnant women who were deficient in vitamin D (i.e. they had less than 50 nmol per litre in their blood1) were more likely to have children who scored in the bottom 25 percent in tests for gross and fine motor development than were children whose mothers were getting enough vitamin D.
The tests were carried out when the children were aged two and a half and they assessed the children’s coordination – kicking a ball, balancing and jumping – and their use of fine motor skills – holding a pencil and building a tower with bricks.
Lack of vitamin D in pregnancy was also found to affect a child’s social development at the age of three and a half. However, no associations were found between the mother’s vitamin D levels and her chiId’s IQ or reading ability at the ages of seven and nine.
Previous evidence from animal studies has shown that the neuro-cognitive development of foetuses is detrimentally affected when the mother has low levels of vitamin D. Interactions between vitamin D and dopamine in the brain of the foetus may play a crucial role in the neurological development of brain areas controlling motor and social development.
The finding of the current study2 reinforces the importance of vitamin D, which is derived from sunlight and diet, to the human body. In addition to the findings in this study, vitamin D is also proven to regulate the amount of calcium and phosphate in the body, which is vital in reducing the risk of osteoporosis. Sufficient vitamin D may also be associated with reduced risk of cardiovascular disease, infectious and autoimmune disease and diabetes.
Lead author Dr Andrea Darling from the University of Surrey said:
‘The importance of vitamin D sufficiency should not be underestimated. It is well-known to be good for our musculoskeletal systems, but our research shows that if levels are low in expectant mothers, it can affect the development of their children in their early years of life.
‘Vitamin D is found in oily fish (e.g. salmon, sardines, mackerel and fresh tuna) and in small amounts in red meat, eggs, fortified fat spreads and some breakfast cereals. Consumption of oily fish will also give other health benefits (e.g. from omega-3 fatty acids). However, unless a large portion of oily fish (100g) is eaten daily it is difficult to get the recommended daily intake of 10 micrograms per day from food alone.
‘Many pregnant women, especially those from minority groups with darker skin (e.g. African, African-Caribbean or South Asian), will still need to take a 10 micrograms vitamin D supplement daily, particularly in the autumn and winter when vitamin D cannot be made from the sun in the UK. However, it is important to remember that ‘more is not necessarily better’ and it is important not to take too much vitamin D from supplements as it can be toxic in very high doses.’