Getting plenty of vitamin D could help boost fertility in women, say experts.

Vitamin D – aka the ‘sunshine vitamin’ – is produced in the skin after exposure to sunlight and can also be found in some foods.

And now scientists from the University of Edinburgh have found a link between vitamin D and ‘reproductive success’.

Their findings come from monitoring a flock of sheep on a remote Scottish island.

But they’re confident the results will be mirrored in other mammals – most importantly humans.

Health and wellbeing expert Jonathan Evans, founder of world-leading supplements firm MANFLU, says the evidence could prove life-changing for many couples desperately trying for a baby.

He said: “We’ve long known that vitamin D is essential for healthy bones and teeth in humans, and it has been linked to other health benefits.

“When we created our new MANFLU Soup A Hero product we enhanced it with 13 select vitamins and minerals for immune support, to reduce tiredness and support energy release.

“We of course included vitamin D as people can be deficient at this time of year.

“And now this piece of research offers another reason to ensure you’re getting enough, either through plenty of time outdoors or through the right foods, such as our vitamin D enriched ’Soup a Hero’ chicken soup.”

Some other foods rich in vitamin D include tuna, sardines, milk, yoghurt, egg yolks and cheese.

Dr Richard Mellanby, Head of Small Animal Medicine at Edinburgh University’s Royal School of Veterinary Studies, says the wild sheep they surveyed on the island of St Kilda were measured for concentrations of a marker linked to vitamin D in the blood.

Sheep with higher levels of vitamin D in their blood at the end of the summer went on to have more lambs in the following spring.

The research has been published in the journal Scientific Reports.

Dr Mellanby says: “Our study is the first to link vitamin D status and reproductive success in a wild animal population.

“Low levels of vitamin D appear to dampen the immune response and make the body almost attack itself.

“And what we have shown for the first time in wild animals is that vitamin D is linked with important life history events, like giving birth.”

The research has also been welcomed by fertility campaigners.

Susan Seenan, chief executive of the Infertility Network UK, said: “What is important to remember when trying to conceive is to try to stay as healthy as possible overall: eating a balanced diet, getting enough exercise and taking care of your emotional health.

“Recent studies suggesting a link between sunshine/vitamin D and improved fertility are interesting; couples may want to consider boosting their sunshine exposure.”

The news comes after a separate study, by Dr Emad Al-Dujaili, of Queen Margaret University, Edinburgh, found that boosting vitamin D intake can raise energy levels.

Vitamin D deficiency is a growing problem in the western world, linked to increasing instances of rickets, irritable bowel syndrome and even leukaemia .