The Whys and Wherefores of Vitamin D Supplementation
We have all seen the controversial newspaper headlines, debating whether or not we should be taking vitamin D. It is so confusing to know what to do for the best. I am here to give you the facts, so that you can make an informed choice for yourself.
Government guidelines (2016) state that everyone above the age of 1 year old should think about supplementing vitamin D at 10mcg of (400 IU) daily, from October to March every year. When sunlight exposure is inadequate, dietary vitamin D is difficult to obtain.
Certain groups of people have a higher risk of vitamin D deficiency, and are therefore being advised to take a supplement all year round. For example:
● Pregnant and breastfeeding women
● Infants and young children under 5 years of age. A deficiency in maternal vitamin D can result in low bone mineralisation for the child.
● People who have obesity
● Autoimmune sufferers
● People over the age of 65
● People with low, or no exposure to the sun, and those with darker skin
Where do we get Vitamin D from?
Vitamin D can be synthesized from ultraviolet light on the skin, converting it to an inactive form of vitamin D. It becomes active when it reaches the liver and kidneys. In the summer months we apply high factor sun cream, and wear clothing to protect our skin, so that the UVB rays do not penetrate the skin. 20 minutes of daily exposure to direct sunlight, without protection, will produce enough vitamin D from April to September.
Small amounts of vitamin D are found in oily fish, eggs, liver and butter, but not enough to maintain optimal levels.
What does Vitamin D do?
● Vitamin D plays a fundamental role in maintaining a healthy bone metabolism, by regulating Calcium and Phosphorus absorption, and slowing down bone density loss.
● It enhances our natural immune response against some infections, particularly respiratory tract infections. It has anti-inflammatory properties too.
● Vitamin D plays a role in cardiovascular health, the specialisation of body cells, Insulin and blood sugar regulation, the prevention of autoimmune conditions, gut microbiome health (bacteria environment), and mood.
Symptoms of Deficiency include:
● Softening of bones and teeth
● Lack of energy and fatigue
● Poor immune system
● Muscle aches
There is little tissue storage of vitamin D, so toxicity is very rare. Symptoms include muscle weakness, irritability and nausea.
If you have a chronic disease the NHS will test your vitamin D levels. Otherwise, there are private tests, usually pin prick tests, that can be carried out at home (eg, Thriva.co.uk).
Supplementation: Which one to choose
● Vitamin D can be bought in tablets, drops and sprays, the latter being the best absorbed.
● D2 is vitamin D in its vegan form, and D3 is derived from lanolin.
● Vitamin D is oil soluble, so those supplements containing oil may increase its absorption.
● You may notice some supplements also contain Vitamin K2. Vitamin K promotes calcium accumulation in your bones, and compliments vitamin D.
● Vitamin D can interact with anticonvulsants, anti TB drugs, and drugs used in anaesthesia, so always tell your doctor you are taking it.
I hope that you now feel confident about why you are supplementing vitamin D, when to take it, and what to look for in a good effective supplement.