Can Vitamin D boost your immunity?
There are many things we can do to support a healthy immune system throughout the year including sleeping well, exercise, relaxation, and stress reduction. There are also certain supplements we can use to further boost our immune systems through the winter months, when we tend to be most likely to be laid low by a virus. This article focuses on Vitamin D, a key supplement for a healthy immune system and one which has received a great deal of press coverage in relation to its potential to improve immunity against Covid-19.
So, what is Vitamin D, why do we need it, and what, if any, Vitamin D supplements should we be taking?
What is Vitamin D?
We produce Vitamin D when we are exposed to sunlight. This occurs when our skin cells are exposed to ultra-violet light. In the UK, therefore, we are most likely to have suboptimal levels of Vitamin D through the winter months when we have less exposure to sunlight.
Who is at highest risk of having low Vitamin D levels?
Pregnant women, breastfed babies, children under 5
People with darker skin - those with African and Asian ethnicity may require 3-5 times the amount of sun exposure
People who use a lot of sunscreen
Those who are obese or underweight
Elderly people - our Vitamin D production falls as we age by at least 50%
People who spend a lot of time indoors
Why is Vitamin D important?
Vitamin D has so many important functions in the body and is often described as a more like a hormone. Here are some key things that Vitamin D is involved with:
Bone health - without adequate Vitamin D we may be more prone to bone density issues (osteoporosis), fractures and in children, Rickets
Brain health - Vitamin D is vital for proper nerve cell and brain development. Cognitive impairment, depression and even autism have all been associated with low levels of Vitamin D
Immune health - Vitamin D plays a critical role in proper immune system function. It has been linked to auto-immune development, particularly if there was deficiency in early life. These include type 1 diabetes, systemic lupus erythematosus (SLE) and multiple sclerosis (MS)
Cancer - there is a strong association between low Vitamin D and a poorer prognosis of patients with cancer. Vitamin D has been suggested to balance inappropriate inflammatory processes associated with cancer progression
What are the symptoms of low levels of Vitamin D?
Remember that even if you don’t have any of the following symptoms, it may be still worth checking if your levels are optimal. Symptoms tend to appear when we have a more significant deficit:
Bone pain or tenderness
Muscle pain
Fatigue
Depression
Stress fractures
Poor bone density (osteoporosis)
Vitamin D and COVID-19
There appears to be strong evidence to suggest that good levels of Vitamin D are linked to better survival rates in patients who have contracted COVID-19. We know that Vitamin D is important in healthy immune function, so it may be sensible to keep our Vitamin D levels optimal as a protective measure.
How do I know if my Vitamin D levels are low?
A 2011 study by the Institute of Medicine (IOM) suggested that we should have Vitamin D levels of at least 50 nmol/L, however, it has been suggested that optimal levels may be 125 nmol/L. It is possible to have a simple blood test to evaluate your Vitamin D levels, either through your GP or healthcare practitioner. There are inexpensive home blood test kits available, however it is advisable to do this in conjunction with a healthcare practitioner so they can guide you through the results and advise on supplements where appropriate.
Which Vitamin D products are best?
The most highly absorbable form of Vitamin D is the D3 form. You may see another commonly used form D2 - It is best to avoid it as it has been found to be less effective at raising the levels of Vitamin D in the blood.
If you are looking to maximise the benefits of using Vitamin D3, it is also sensible to consider using a supplement which also contains Vitamin K2. It works synergistically with Vitamin D3 in maintaining bone health. To ensure that you get the best available products speak to your healthcare practitioner.
All sources and references associated with this article can be found here.