There has been much said about vitamin D on social media platforms in the light of immunity and specifically with regard to Covid19. Vitamin D is an important co-factor in immunity. Information circulating recently has been a little ambiguous and potentially misleading, so I thought I’d clarify a few points.
Firstly, more is not necessarily better. There are recommended amounts for most nutrients and vitamin D is no different. Remember the “juice” that could be found in the fridge section of the supermarket? The “juice” that had so much sugar in it that it did not need to be sold from the refrigeration units, it could happily sit in the ambient drink section of the supermarket due to the high sugar content. Those who drank excessive amounts turned an interesting shade of orange. This was due to overdosing on the beta carotene present in the drink. The consumers concerned simply consumed excessively on a single product and therefore overdosed on a single nutrient that was present in the product.
Vitamin D is a fat soluble vitamin. This means that unlike water soluble vitamins such as vitamin C you will not simply “wee it out”. It will be stored in the body. Now I’m not saying you will change colour! What I am saying is that there’s a healthy level of vitamin D in a good diet. If you believe you or your family do not have a good diet that embraces all nutrients then perhaps this is a good time to look at introducing some balance. Nutrients impact on each other and can be interactive with each other. For example healthy bones require an interaction between vitamin D and calcium. The vitamin D helps absorb the calcium.
If taken, the recommended supplement for those over the age of 5 years is 10 micrograms. Note, this is not milligrams, but micrograms there is a 10 fold difference in this. Advice should always be sought on any supplementation, especially for vulnerable groups. Reliable advice from the NHS is here
https://www.nhs.uk/live-well/healthy-body/how-to-get-vitamin-d-from-sunlight/
Most of us get about 90% of our vitamin D from sun exposure, but this is dependent on other factors too, such as skin colour, ageing, BMI, access to the outdoors and not least the weather! Many of us can get out, exercise and get a dose of sunshine that will help with our vitamin D status and our mental health, so this is an excellent idea.
Meanwhile food sources of vitamin D can provide additional benefits, such as fibre and other macro and micro nutrients. Cooking methods matter too, high temperature cooking methods, such as frying, are less likely to preserve vitamin D than baking for example. Baked salmon loses little or no vitamin D, salmon fried may lose 50% of the vitamin D content. Farmed salmon may contain only 25% of the vitamin D found in wild salmon, but not everyone can afford that or would choose to eat it and there are alternatives!
Other food sources of Vitamin D include liver, egg yolks, cheese, butter, oily fish such as salmon, herrings, kippers, sardines and mackerel, meat and, particularly important for vegetarians, fortified foods such as breakfast cereal, juice, some plant based milks and spreads and naturally occurs in mushrooms.
So a quick fix of a supplement is there for those who want it, or need it. However, for many of us a slight shift in diet and lifestyle may benefit us in more ways than just improving our vitamin D intake and may be the opportunity to look critically at our daily food consumption and exercise levels which is likely to impact positively on our general health and wellbeing, including immunity.