The magic of vitamin D - The sunshine vitamin

Research in recent years has begun to show the critical importance of vitamin D for our overall health and wellbeing.

Vitamin D was discovered around 100 years ago, when sunlight was found to help heal children with rickets. Since then we’ve known that Vitamin D is vital for keeping blood calcium and phosphorous levels in balance, which is important for healthy bones, teeth and muscles.

However, more recently research has found that vitamin D’s importance goes way beyond this. The impact of vitamin D on the body’s immune and inflammation system is beginning to become known, and Vitamin D deficiency is now linked to a wide range of diseases, including:

• A range of cancers

• Diabetes

• Multiple Sclerosis

• Rheumatoid Arthritis

• Hypertension

• Heart Disease

• Infectious diseases, including Flu (perhaps one reason flu is prevalent in winter is that our vitamin D stores are much lower) and possibly Covid 19 (this makes sense given the vitamin’s relationship to our immune and inflammatory systems. There isn’t enough evidence for this to be conclusive, but research will continue and we’ll know more in time).

Worryingly, however, multiple research studies in different geographical areas and across different demographics, show that in many populations, upwards of 50% of the population is vitamin D deficient. Despite living in Africa, I was tested last year and was found to be Vitamin D insufficient!

Our main source of vitamin D is from the sun. However, did you know that:

• In the UK there is insufficient sunlight for your body to manufacture vitamin D from sunlight during the months of October to March/April.

• In the US, if you live anywhere north of Atlanta, Georgia there is insufficient sunlight for your body to make vitamin D between the months of November and February.

So how can you ensure you get enough?

You won’t be surprised to know that the most reliable (and fun) way is to get out in the sun. But this is what you need to know. In the northern hemisphere sun exposure only gives you what you need during spring, summer and autumn. There’s not enough UVB in the winter sun for your body to make ANY vitamin D (see above).

During these seasons you need to be in the sun:

• With bare arms and/or legs

• o For 5-15 minutes

• o 3 times per week

• o In the middle of the day (11am-3pm)

• o With no sunscreen on (if you are fair skinned and prone to burning, ensure you do not exceed the safe limit for your skin).

Food sources of vitamin D are limited, particularly for vegans and vegetarians. Foods that are fortified with vitamin D provide a good option, particularly for those who don’t eat fish and meat. Here are the main food sources:

• Wild caught oily fish such as salmon, mackerel, herring and sardines

• Red meat

• Cod liver oil

• Egg yolks

• Fortified dairy and non-dairy milks

• Fortified cereals

• Certain mushrooms (most commercial mushrooms are grown in the dark, so wild mushrooms or those grown in UV are the only varieties that contain Vitamin D)

During the winter months you will almost certainly need a vitamin D supplement, and possibly also at other times of the year. In the UK the NHS recommends 400IU per day for everyone aged 1 to 70 during the winter months but not more than 4000IU. Professor Michael Holick who wrote the book “The Vitamin D Solution” recommends 1000IU per day for children and 2000IU per day for adults.

If you are unsure what dose it right for you, you should always check with your doctor.