As we near the end of what feels like a very long winter, our last summer holiday a hazy memory and the next opportunity to travel still a way off, stores of vitamin D will be at an all-time low. However, with the clocks going forward and brighter days just around the corner, lets refresh our knowledge of all things vit D with a look at some of the research surrounding vitamin D and COVID-19.
Vitamin D is in fact not a vitamin at all but a fundamental steroid hormone that is produced in our skin in response to sunlight with a wide-ranging impact on the entire human body, and in particular, on immune function. Receptors for this sunshine vitamin have been identified in every single one of our immune cells suggesting powerful immunoregulatory properties.
In the UK, due to our position on the earth we are simply not able to produce enough vitamin D, and as a population we have chronically low levels. The integral role of vitamin D to our overall health meant that at the onset of the coronavirus pandemic last year, government recommendations to supplement through the winter months were increased to supplement year-round. Since then, there has been much debate and discussion around vitamin D in the prevention and treatment of COVID-19, and the research has produced some very interesting results.
At the beginning of the pandemic there was a lot of press covering the potential link between vitamin D and coronavirus outcomes and some hospitals in the UK began prescribing high doses of the vitamin with positive effects. Subsequently, a review carried out by NICE and Public Health England in June 2020 concluded that there was not enough evidence to prove that vitamin D was helpful against COVID-19, however this review has many flaws in itself. It was heavily criticised for being too narrow – including only 5 studies, for looking at studies that were out of date, and at those that used a dosage too low to make a difference or too high and considered dangerous.
Despite this, in December of last year, 150 leading scientists, doctors and authorities wrote an open letter to governments worldwide calling to increase vitamin D use to combat COVID-19. The majority recommended supplementing with 4,000 IU – 10 times the level currently recommended in the UK, and some personally admitted taking in excess of up to 10,000 IU.
In addition, over the past 12 months, interventions with vitamin D around the world, including the UK, France, Spain, South Korea and Singapore have been shown to reduce the severity of COVID-19 infections and improve outcomes.
Vitamin D and the immune system
Low levels of vitamin D have long been linked to a higher risk of viral respiratory tract infections, as well as a host of serious illnesses including cardiovascular disease, hypertension, skin conditions, autoimmunity, neurological conditions and cancer. This is because vitamin D is integral for immune function:
- Vitamin D has a powerful effect of on our genetic ability to fight viruses, switching on or off processes that help to protect us.
- The impact on ‘T cells’ – a collection of white blood cells that live in the skin and mucosal layers such as the gut and respiratory tract and create a barrier to prevent pathogens from entering the body. Vitamin D enhances the production and activity of these immune cells, helping to identify, neutralise and destroy invading viruses and bacteria.
- Vitamin D has an ability to regulate our immune system, cases of long-covid in particular appear to be a result of something called a ‘cytokine storm’ – where the immune system has gone into overdrive causing long lasting damage.
On average, the UK population has less than half (19ng/ml) the recommended levels shown to support good health and resistance to infection. So, while the daily dose suggested by Public Health England of 400 IU/10 mcg may be adequate to prevent severe deficiency, resulting in rickets, it is far too low to achieve levels needed for optimal immune function. Some studies show that up to 250mcg per day, or up to 20 times(!) the current recommendation is required to maintain blood levels (40-60ng/ml).
Bearing in mind that it is impossible to get enough vitamin D through food and the fact that the majority of us have spent the past 12 months indoors, it is sensible to consider supplementing in the long term in order to give our immune systems the best possible chance of fighting any future threats to our health.
Stay healthy every day
Get More Vits now have a wide range of products to help us keep topped up with a daily dose of vitamin D, and most importantly – in a tasty way to suit your lifestyle. Try our still Mango & Passionfruit drink, Orange flavoured vitamin D spray, Orange & Mango effervescent tablets or our vitamin D supplements.