Nutshells Series: Vitamin D

Vitamin D

The Nutshells series gives you all the essentials on nutrition in, well, a nutshell!  These quick guides will help you to understand the important macronutrients (think Carbohydrates, Proteins, Fats etc), vitamins and minerals and how they can improve your overall health and wellbeing.   First up, Vitamin D.

Vitamin D has become quite the celebrity during this Covid-19 pandemic with some debate over whether it can help in the treatment and prevention of the virus.  They are still doing studies with the jury still out, but what we can tell you is that Vitamin D has a lot of benefits.  

Where can I get Vitamin D from? 

1.  The Sun 

Let’s start by crushing a myth.   Natural sunlight does not give you Vitamin D.  Natural sunlight helps your body to create Vitamin D.  Isn’t it cool how your body works!   

Here is the important thing to note:  You need sunlight to create Vitamin D to help your body work to its full potential.   20 minutes of sunshine per day in the summer will give you more than enough exposure.  People with dark skin, such as those of African, African-Caribbean or south Asian origin, will need to spend longer in the sun to produce the same amount of vitamin D as someone with lighter skin as their skin pigmentation screens out the relatively limited sunlight more effectively.

For clarity, wearing sunscreen will prevent almost all Vitamin D creation in your body (SPF 15 will decrease Vitamin D production levels by 99%).  Give yourself 20 minutes sunscreen free per day but do follow all of the guidance for the prevention of skin cancer.  

2.  Foods

Vitamin D is extremely rare in foods. It’s found in fish, cod liver oil, mushrooms, liver and eggs – but usually not in substantial amounts (except in cod liver oil).

Farmed varieties of fish contain very little vitamin D compared to the wild varieties. The only reason we even get vitamin D from foods like milk and cereal is because these foods are fortified with it — it doesn’t naturally occur.  

3.  Supplements 

We recommend Vitamin D supplements to boost the levels in your body, especially between September and March.  You can pick these up from your local pharmacy or supplement store (and even most supermarkets now).  Check out the back of the supplement pack and look for the Vitamin D supplements between 1,000IU and 4,000IU.  Do not exceed the latter without speaking to your Doctor first. Your Doctor may recommend a higher dose if your are struggling with Vitamin D deficiencies.   

Why is vitamin D important? 

Without enough activated vitamin D in the body, dietary calcium cannot be absorbed. Calcium is essential for signaling between brain cells, development of bone, and tooth formation.  Extreme deficiencies can cause rickets.  

Studies also reveal that low vitamin D levels in the body are associated with:

  • Increased loss of muscle strength and mass as we age
  • Increased risk of cancers
  • Lower levels of immunity
  • Higher blood pressure
  • The development of neurological disorders
  • The development of diabetes.


Anything else you should know? 

There’s no risk of your body making too much vitamin D from sun exposure, but always remember to cover up or protect your skin before the time it takes you to start turning red or burn.  

You can make too much Vitamin D for your body to handle by overdosing on supplements.  

The Merck Manual notes:

Taking very high daily doses of vitamin D—for example, 50 or more times the recommended daily allowance (RDA)—over several months can cause toxicity and a high calcium level in the blood (hypercalcemia).  Early symptoms are loss of appetite, nausea, and vomiting, followed by excessive thirst, weakness, nervousness, and high blood pressure. Because the calcium level is high, calcium may be deposited throughout the body, particularly in the kidneys, blood vessels, lungs, and heart. The kidneys may be permanently damaged and malfunction, resulting in kidney failure.’
You would have to swallow a lot to do that but do follow your countries recommended daily allowance.  

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