Where does Vitamin D come from and how much do we need?
Everyone needs a daily vitamin D intake of 10 micrograms (the equivalent to 400iu (the international unit)). We can acquire a little vitamin D by eating a balanced diet (vitamin D is found in oily fish, red meat and egg yolks as well as fortified foods). Our bodies also make vitamin D from exposure to direct sunlight. In Spring and Summer in fact, we meet most of our daily vitamin D needs from sunlight exposure providing we are outside with our legs or arms exposed for at least 20 minutes.
When do we need to supplement?
Official advice from Public Health England is that everyone in the UK should take a vitamin D supplement over Autumn and Winter because during this period in the Northern Hemisphere, the sun isn’t strong enough for our bodies to make sufficient vitamin D.
- Are pregnant
- Have very limited outdoor exposure
- Have a darker skin tone
- Use sunscreen very liberally or cover the majority of your body in the summer months
Vitamin D acts on almost every single system in the body. Vitamin D plays a vital role in balancing calcium levels in the body and it is because of this that it so important for bone (and teeth) health. In children and adolescents, vitamin D deficiency is associated with Rickets, which is now worryingly on the increase. In older people, a lack of vitamin D can reduce bone mineral density, increasing the risk of osteoporosis and bone fractures. Ensuring you meet the recommended vitamin D intake can help ensure good bone health.
It is probably less well known that vitamin D is also important for heart health. Low vitamin D status is associated with high blood pressure, high cholesterol and inflammation, all of which are risk factors for cardiovascular disease. The good news is that there is evidence indicating that supplementing with vitamin D can reduce these risk factors.
As well as causing inflammation in the blood capillaries, vitamin D deficiency is also associated with inflammatory conditions such as Inflammatory Bowel Disease (or Crohn’s disease), asthma and Type 2 Diabetes. Supplementation therefore may be useful for you if you suffer from any chronic inflammatory conditions.
There is also emerging evidence that vitamin D is necessary for neurological development in the growing brains of children and for protecting brain health in adults. Vitamin D supplementation may reduce risk of autism (if used during pregnancy or in infancy), improve depression and protect against cognitive decline.
And it’s especially reassuring to know that at this time of year when we are surrounded by coughs and sneezes, that vitamin D supplementation can bolster our immune systems and protect against us against colds and flu!