Bring me sunshine or a vitamin D supplement

So vitamin D is the latest trend in the news at the moment. Recently the NHS in the UK announced that increasing vitamin D intake, especially in the winter months can help prevent millions of colds and flu cases and possible save lives (1). So why the sudden trend in Vitamin D and its importance? This is mainly due to recent studies that have come out, especially in places where sunshine is not common and linking this to underlying health conditions. Cancer, diabetes, high blood pressure, poor semen quality, depression, and osteoporosis. There seems to be no limit to the illnesses that vitamin D can affect. Even though knowledge connecting low levels of vitamin D with severe health issues is available, people  are still getting far too little of the vital vitamin (2).

To take a step back what is vitamin D and why is it so important for your health? Vitamin D refers to a group of fat soluble steroids responsible for increasing intestinal absorption of calcium, iron, magnesium, phosphate, and zinc. In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol) (3). This was first made present in the late 1800’s when it was discovered that bathing children in sunshine helped improve bone structure and prevent rickets.

Anyone taking calcium knows that you need to take it with vitamin D. It's needed because vitamin D promotes calcium absorption in the gut and maintains blood calcium levels to enable normal mineralisation of bone and prevent abnormally low blood calcium levels that can then lead to tetany. Vitamin D insufficiency leads to secondary hyperparathyroidism (overactive parathyroid glands) that causes increased bone loss, osteopenia, osteomalacia, osteoporosis, and increased fracture risk (4).

So what is the best way to get vitamin D?

Our body creates vitamin D from direct sunlight on our skin when we are outdoors. From about late March/early April to the end of September, most people should be able to get all the vitamin D we need from sunlight in the UK. We also get some vitamin D from a small number of foods, including oily fish such as salmon, mackerel, herring and sardines, as well as red meat and eggs.  Vitamin D is also added to all infant formula milk, as well as some breakfast cereals, fat spreads and non-dairy milk alternatives. The amounts added to these products can vary and may only be added in small amounts. Manufacturers must by law add vitamin D to infant formula milk. Another source of vitamin D is dietary supplements (5).

The most natural way to get vitamin D is by exposing your bare skin to sunlight (ultraviolet B rays). This can happen very quickly, particularly in the summer. You don’t need to tan or burn your skin to get vitamin D. You only need to expose your skin for around half the time it takes for your skin to begin to burn. How much vitamin D is produced from sunlight depends on the time of day, where you live in the world and the colour of your skin. The more skin you expose the more vitamin D is produced.

You can also get vitamin D by taking supplements. This is a good way to get vitamin D if you can’t get enough sunlight, or if you’re worried about exposing your skin. Vitamin D3 is the best kind of supplement to take. It comes in a number of different forms, such as liquids, tablets and capsules, but it doesn’t matter what form you take, or what time of the day you take it.

Different organisations recommend different amounts of vitamin D supplement to take each day. The Vitamin D Council recommends taking larger amounts of vitamin D each day than other organisations, because smaller amounts aren’t enough to give you what your body needs. Most people can take vitamin D supplements with no problems. However, if you have certain health problems or take certain medicines, you may need to take extra care (6).

Can you get take too much vitamin D?

Vitamin D toxicity implies that vitamin D levels in the body are so high that they cause harm. Vitamin D is a fat-soluble vitamin. In contrast to water-soluble vitamins, the body has no easy way of getting rid of fat-soluble vitamins. For this reason, excessive amounts may build up inside the body. The exact mechanism behind vitamin D toxicity is complicated and isn’t fully understood at this point. However, we know that the active form of vitamin D functions in a similar way as a steroid hormone. It travels inside cells, telling them to turn genes on or off. Usually, most of the body’s vitamin D is in storage, bound to either vitamin D receptors or carrier proteins. Very little “free” vitamin D is available. However, when vitamin D intake is extreme, the levels can become so high that there isn’t any room left on the receptors or carrier proteins.

This may lead to elevated levels of “free” vitamin D in the body, which may travel inside cells and overwhelm the signalling processes affected by vitamin D. One of the main signalling processes has to do with increasing the absorption of calcium from the digestive system. As a result, the main symptom of vitamin D toxicity is hypercalcemia – elevated levels of calcium in the blood. High calcium levels can cause various symptoms, and the calcium can also bind to other tissues and damage them. This includes the kidneys (7).

So to summarise, spending more time outdoors with your skin exposed to the sun as well as having eggs and oily fish will ensure that during the summer months you have a good level of vitamin D is your body. IN the winter months when most people spend time indoors and wrapped up in jumpers and hats, I recommend taking a vitamin D3 supplement. Your diet should be vast and should be rich in vitamins, minerals and you should always stay hydrated. Processed foods should be avoided as much as possible. The plate you eat should be rich in colours, such as greens, reds, oranges and whites.

If you think you may have vitamin D deficiency or require general guidance on nutritional support and how to live a balanced lifestyle please contact me at habs@urbanplatehealth.com or visit my website by going to www.urbanplatehealth.com

References:

1. 'Add vitamin D to food to prevent colds and flu', say researchers - http://www.nhs.uk/news/2017/02February/Pages/Add-vitamin-D-to-food-to-prevent-millions-of-colds-and-flus-study.aspx
2. New study: we're not getting enough vitamin D - http://sciencenordic.com/new-study-were-not-getting-enough-vitamin-d
3. Holick MF (March 2006). "High prevalence of vitamin D inadequacy and implications for health". Mayo Clinic Proceedings. 81 (3): 353–73. doi:10.4065/81.3.353. PMID 16529140.
4. Vitamin D Deficiency - http://www.medicinenet.com/vitamin_d_deficiency/page3.htm
5. The gables Medical Centre: How to get vitamin D - http://www.thegablesmedicalcentre.co.uk/Library/livewell/topics/summerhealth/vitamin-d-sunlight
6. How do I get the vitamin D my body needs? - https://www.vitamindcouncil.org/about-vitamin-d/how-do-i-get-the-vitamin-d-my-body-needs/
7. How Much Vitamin D is Too Much? The Surprising Truth - https://authoritynutrition.com/how-much-vitamin-d-is-too-much/

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