Children who do not get enough vitamin D 'are 10% more likely to suffer from depression'
Children with high levels of vitamin D levels are less likely to suffer from depression, claim scientists.
A new study shows those with highest levels of the ‘sunshine vitamin’ have a 10 per cent lower risk.
It is the first time research has looked at the impact of vitamin D on depression in children, although it is known that higher levels in adults benefits their mental health.
Children can boost their vitamin D levels by eating oily fish like tuna and having exposure to sunlight
Encouraging children to eat more vitamin D-rich foods such as oily fish like tuna and fortified breakfast cereals along with exposure to sunlight – the vitamin is made by the action of sunlight on the skin – could protect them throughout their teens and beyond, it is claimed.
The findings from the Children of the 90s study run by the University of Bristol, which has been charting the health of thousands of children since their birth in the early 1990s.
The study looked at vitamin D levels in over 2,700 children by taking blood tests when they were 9 years and 8 months old.
They then re-tested the children at the age of 13 years and eight months and found those with higher levels of vitamin D were 10 per cent less likely to show signs of depression.
Those with higher levels were also more likely to show a decline in depressive symptoms between the ages of 10 and 13.
The study investigated levels of two forms of the vitamin – vitamin D2 and vitamin D3 – and found the strongest anti-depression link with vitamin D3.
Vitamin D supplements are available in two forms but it was previously unclear whether they both had an effect on depression.
The study suggests new trials investigating whether vitamin D supplements can prevent depression or improve mood in depressed people should use vitamin D3.
Lead researcher Dr Anna-Maija Tolppanen, of the school of social and community medicine at Bristol University, said further research is needed before a change in medical practice could be recommended that actively investigated vitamin D levels in children with depression or routinely gave them supplements.
She said: ‘Given the importance of depression in childhood and adolescence and the relative ease with which vitamin D levels could be increased with supplements, randomised controlled trials to assess its effectiveness in preventing depressive symptoms would be appropriate.
‘Certain studies show that high levels of vitamin D are associated with numerous other health benefits, including better respiratory health, lower risk of several types of cancer, asthma and cognitive decline, but these studies have often provided mixed and inconclusive results’ she added.
Tuna steak: Oily fish is a good source of vitamin D
Oliver Gillie, who runs the Health
Research Forum and campaigns for greater awareness of vitamin D
deficiency, said scientists knew the vitamin D3 form was superior to
vitamin D2, but many consumers were not aware of the difference.
Although vitamin D3 is widely used in supplements for adults, supplements for children often contained the less potent form D2 for historical reasons.
Changing the formula might need massive trials and expense to meet EU regulations, he said.
But too many children were not getting adequate intakes of vitamin D, he said, with only around 5,000 children a year are getting supplements on the NHS.
Although the vitamin is found in salmon, tuna and other oily fish, and is routinely added to milk, diet accounts for very little of the nutrient that actually makes it into the bloodstream.
Canned tuna does not have the same amount of oil as fresh tuna, with the canning process reducing levels of vitamin D and omega 3, which is good for the brain, but it is widely eaten in sandwiches.
Mr Gillie said ‘Consumers should be made more aware of the differences between different types of vitamin D in supplements because it is almost impossible to get enough through a healthy diet. There is less vitamin D even in fish than people might think.’
In the UK, the Food Standards Agency does not recommend a specific daily dose of vitamin D unless you are elderly, pregnant, Asian, get little sun exposure and eat no meat or oily fish when 10mcg is advised.
It says daily supplements of 25mcg are unlikely to cause harm.
The danger with taking excessive doses for long periods is that the body absorbs too much calcium, which could weaken bones and possibly damage liver and kidneys.