The iceberg nutrient... Vitamin D is most widely known as the nutrient that is necessary to aid calcium absorption which then prevents rickets and therefore it is assumed if you don’t have rickets then you don’t have a deficiency. However, there is now literature that associates low vitamin D status with an increased risk for a wide variety of disorders (including in fact Covid-19 as it plays a huge role in immunity).  It is actually known as the iceberg nutrient because, as the image of an iceberg suggests, deficiency could be causing a myriad of problems underneath the surface.

Now, vitamin D can take many forms, but standard blood tests detect only one, an inactive precursor that can be stored in your body. So, a test result may say you have adequate levels, but your body may not be in a good enough state to turn it into its active form.  

Your gut bacteria determine how much vitamin D is converted. Our gut microbiome (the bacteria, viruses and other microbes living in our digestive tracts) plays an important role in our health and risk for disease in ways that are only beginning to be recognised.  In regard to vitamin D, the more variety of bacteria in a person’s gut the more the precursor vitamin D is turned into the active form.  Whilst greater gut microbiome diversity is necessary for converting vitamin D, it is also necessary for overall health and is why I chose to focus on this area as my speciality – everything starts in the gut (said Hippocrates!).

Optimal Vitamin D levels play a positive role in making sure that your body functions the way it’s meant to. There are Vitamin D Receptors located in tissue throughout your body and in all the major organs and vitamin D interacts with over 3,000 genes. 

Insufficiency is associated with many diseases. The benefit of an adequate vitamin D level to each individual will be better overall health and a reduction of illnesses. In addition to rickets, bone disease and osteoporosis, vitamin D insufficiency is associated with many other diseases including: tuberculosis, psoriasis, multiple sclerosis, inflammatory bowel disease, type-1 diabetes, high blood pressure, increased heart failure, myopathy, breast and other cancers. 

It is projected that the incidence of many of these diseases could be reduced by 20%-50% or more, if vitamin D deficiency were eradicated by increasing vitamin D intakes through increased sun exposure, vitamin D rich foods or supplements and ensuring your gut microbiome is balanced to convert it into its active form.

It only take 10-15 minutes. You need to expose your skin 10-15 minutes per day in the Summer with no sunscreen - face and hands is enough (obviously not if you have very fair skin or skin cancer) and this will produce enough vitamin D to be stored in your body over the Summer months. During the Winter however you do need to take a supplement.  An adult needs an intake up of to 4,000IU per day depending on body weight but taking 1,000IU will be sufficient if you have stored up over Summer.  

Food sources of vitamin D. Food has very low amounts of vitamin D but can contribute a small amount. The best sources are oily fish like wild salmon, full fat milk, eggs and some mushrooms (they are usually labelled high in vitamin D on the packaging). 

So the obvious question here is: “How do you balance your microbiome?” This is not a small feat (and is the basis of my business!) but ensuring variety in your food intake is really important – most people stick to eating the same foods week in week out.  In particular, increase plant foods as gut bacteria feed off different types of fibre – set yourself a challenge to eat 30 different foods a week or more! 

Start low and slow with fibre. Some people with dysfunctional digestive systems may find their symptoms get worse doing this however which is where I come in.  Everyone is individual so I use a tailored approach to find out where the issues are and design programmes that heal and balance the gut so you can go on to eat a full and varied diet for future health.

So, start the 30 different foods a week challenge and get out in the Summer sunshine when it finally appears!