Vitamin D – how much is too much?

Functional nutrition with Carmen Gresa-Alemany

Summer is coming and we have been waiting patiently for it, what a year! Yes, we are all craving those precious rays of sunshine to get some vitamin D in.

Lockdown, working from home, plenty of rain and a cold winter, haven’t allowed us to produce enough of the immune fighter, super vitamin D. How much vitamin D we make in response to sun light, will depend on age, skin colour, nutritional status and exposure time. In order to manufacture enough vitamin D for our needs, it is essential to get 20 minutes of sunshine* wearing shorts and a t-shirt.

Foods like oily fish (salmon, herring, anchovies, sardines, and mackerel), egg yolk, organ meat and fortified foods, contain good levels of vitamin D, but do we eat enough of them?

This precious super hero that behaves like a hormone, deserves a special mention as it is critical for health, even more so in our current situation. Virtually every cell in the body has a vitamin D receptor, which, when bound to vita-min D, can switch more than 200 genes on and off, how cool is this! Optimal levels are important to regulate inflammation, and low vitamin D status is linked to diabetes, risk of respiratory tract infections, hypertension, cardiovascular disease, arthritis, low immunity, obesity, thyroid conditions and depression among others health issues.

It is important to monitor vitamin D levels to ensure they are not too high or too low. In clinic I test vitamin D, with a simple prick test, getting accurate levels 15 minutes after a client walks through the door. Most of the time, I see a deficiency, sometimes severe, but I have also seen toxicity cases, in clients that believed they were staying healthy by keeping up what they thought were good levels. Knowing your level is essential to remain within that golden range, so if results show that you are deficient, we set a target dose to achieve normal levels within a few weeks and if you have toxic levels, we will also set a plan to normalise those.

I get a lot of surprised faces in clinic, even from outdoor people and athletes when they see their results. You can’t overload through sun exposure, but you can with supplements, and excess vitamin D can lead to a build-up of calcium in the blood which might develop into kidney stones and bone pain.

Vitamin D can be toxic, so assessing your vitamin D status is important before you start taking supplements. Why leave it to chance, when calculating your vitamin D levels can be so easy?

*Avoid sunlight between 11am and 4pm when the sun is at its hottest. See page 107 for Bay Cluster advice.

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