Karen's Blog

Vitamin D: What You Need to Know

Vitamin D: What You Need to Know

Most of us will have come across Vitamin D due to its association with bone health. Without vitamin D our bodies cannot effectively absorb calcium, which is essential for good bone health. More recently, due to the current coronavirus pandemic, its vital role in immune system function has been highlighted in the media. Research emerging relating to the pandemic is clearly indicating associations between low vitamin D levels and severity of COVID-19.

As well as being important for bones and the immune system, vitamin D is also important for cardiovascular, gut and mental health. Deficiency also plays a role in certain cancers such as prostate, colon and breast.

Many people, particularly in northern countries, will have low levels of vitamin D over the winter months unless they take a supplement. And since we have recently been spending much more time inside due to lockdown we have had less exposure to sunlight than usual.

Some vitamin D is available from foods such as oily fish, liver, eggs, some mushrooms (if exposed to light), fortified foods such as milk substitutes, cereals and tofu. However, diet alone is unlikely to provide enough vitamin D, exposure of the skin to ultraviolet radiation from the sun is our major source of this vital nutrient.

In April of this year, Public Health England responded to concerns about deficiency and growing evidence of the vital role of vitamin D in immune function, by recommending that everyone should now consider supplementing with vitamin D, not just those in at risk groups.

The NHS current recommendation is that we should consider taking a minimum dose of 10mcg, or 400IU, a day. According to the Institute of Medicine 4000IU is considered the safe upper level of intake. For those who prefer to know their vitamin D status, home testing kits are available to buy online at reasonable prices (starting from £25) and it can be useful to know what your levels are so that you can personalise your supplement dose accordingly.

However, advice on taking vitamin D neglects the fact that vitamins (although D is now considered to be a hormone) do not act in isolation in the body - it may not be as simple as just taking Vitamin D supplements or sitting out in the sun!

For your body to effectively make use of vitamin D, it is important to ensure you have sufficient magnesium. The body needs magnesium to convert vitamin D to its final usable form.

So for anyone who is already low in magnesium, suddenly taking a high dose vitamin D supplement increases the body's demand for magnesium and may push the body into magnesium deficiency. If when taking a vitamin D supplement, or increasing to a much larger dose, someone then experiences symptoms such as headaches, muscle aches/cramps, acid reflux, trouble sleeping, anxiety they may blame the D when it may in fact be due to insufficient magnesium!

Magnesium insufficiency is common in the Western world. There are over 600 roles for magnesium in the body, demand is great for this mineral. It can be obtained from foods such as leafy greens, nuts and seeds, avocados, legumes, wholegrains, cacao. However, many people in the UK do not get enough magnesium from diet and could benefit from supplementing with magnesium.

If you are taking a vitamin D supplement, you should also consider whether you can actually digest and absorb it - we tend to assume that we can! This requires good levels of digestive enzymes and bile to be produced and it is common, particularly in older people, to have sub-optimal digestion. Anyone with type 2 diabetes or gallbladder problems may have impaired production of enzymes and bile which can affect absorption of fat soluble vitamins (vits A,D,E and K). In this case, alternative forms of vitamin D such as sub-lingual or sprays could be considered.

If you are deficient in vitamin D, sometimes large doses are recommended - eg taking one large dose a week rather than daily doses. In my opinion, daily dosing is preferable as this can prevent the vitamin D receptors in the body being overwhelmed and the over-absorption of calcium, which can be a problem in anyone taking calcium supplements.

Vitamin K2 is also a key nutrient when taking vitamin D supplements. Vitamin K2 is responsible for activating proteins which both help move calcium into the bones and prevent it depositing soft tissues such as blood vessels, so helping both bone and cardiovascular health.

Key Takeaways:
• Nutrients such as vitamin D do not work in isolation in the body
• More is not always better!
• We are not what we consume - but what we consume, digest and absorb

Please note if you decide to take any supplements and, are taking any medications, please take advice from your G.P. or pharmacist on any potential contraindications.

If you would like more information regarding vitamin D tests and/or supplements please get in touch. www.karenbrooks.co.uk/contact