Vitamin D plays a vital, key role in your immune system. A
deficiency can lead to fatigue, depression, seasonal affective disorder (SAD)
and a weakened immune system. It’s the weakened immune system that
exposes you to the common cold, but also to flu and other infections. On
that note, vitamin D has been shown to decrease the severity of influenza, as
well as your chances of catching it. Vitamin D is also know to be
responsible for regulating calcium absorption and, therefore, your bone
density. It’s also thought to positively affect many other diseases, including:
colon and breast cancer, respiratory disease and type-1 diabetes.
So, where do we
get vitamin D from?
Vitamin D is vital for human health and we get it through sunlight
exposure and diet. Our main source is from the sun. In the winter, we
spend more time indoors and there is less sunshine when we are outside, so our
exposure level drops below what our bodies need. This decrease is linked
to a weakened immune system and therefore one of the theories behind why most
people get colds in the winter. Vitamin D levels also drop in pregnant
and breast feeding women, young children and older people, darker-skinned
people and those who wear full-body coverings.
We can supplement our decreased production of vitamin D from sunlight
with our diet. Mackerel sardines and fish liver oil are good sources of
natural vitamin D. You can get supplements, too. The only downside of
vitamin D in our diet is that it is not as effective. When you ingest
vitamin D, only 60% of it sticks to vitamin D-binding protein; but when you
make vitamin D through sunlight hitting your skin, 100% of it binds to the
protein. In the group that took supplements, their levels had
What is the best
way to increase vitamin D levels in the winter?
In the northern hemisphere, between the months of September and March, there is insufficient sunlight to ensure optimum vitamin D synthesis. The best way to top up is to enjoy a winter holiday to the southern hemisphere. Therefore, it is essential to maintain a diet high in oily fish, like mackerel and sardines. This diet can be aided by supplementation as well.