Since Covid-19 arrived in our lives, there’s been a lot of chatter about whether we should be taking supplementary vitamin D to help prevent or even treat it.
The vitamin – also referred to as the sunshine vitamin, because our bodies make it from cholesterol when we’re exposed to the light – is especially important in autumn and winter when people tend to spend less time outdoors.
During the winter months, we are advised to take vitamin D supplements to keep our bones and muscles healthy and to support our general health. But in the context of Covid-19, can it be of additional help?
People at high risk from coronavirus – those deemed clinically extremely vulnerable – are already able to get free daily vitamin D supplements to boost their health. However, health experts are cautious to make a clear link.
In June 2020, Paul Chrisp, director of the Centre for Guidelines at the National Institute for Health and Care Excellence, said: “While there are health benefits associated with vitamin D, our rapid evidence summary did not identify sufficient evidence to support the use of vitamin D supplements for the treatment or prevention of Covid-19.”
This was after close analysis of five studies into coronavirus and vitamin D. “We know that the research on this subject is ongoing, and Nice is continuing to monitor new published evidence,” Chrisp added.
An observational study by the UK’s Covid Symptom Study app suggests taking vitamin D supplements could play a small role in reducing the risk of Covid-19 in women, but not men. But further clinical trials were needed, researchers said.
Early on in the pandemic, 1.4 million app users entered data to the Zoe Covid Symptom Study app about their use of supplements. Among this group, more than 445,000 went on to be diagnosed with Covid-19, while 126,000 were thought to have the disease based on their symptoms.
After analysing the data of those who had, and had not had Covid-19, the researchers concluded that multivitamins, vitamin D, omega-3, and probiotic supplements all had a very small but statistically significant protective effect. Vitamin C, zinc or garlic supplements had no detectable effect, they added.
Other scientists said the findings should be treated with caution. Naveed Sattar, professor of metabolic medicine at the University of Glasgow, said: “These are interesting results but, due to the way the study has been conducted, these data absolutely cannot tell us that taking such supplements ‘protects’ against infection from Covid-19.”
So, the jury’s still out on vitamin D’s effect when it comes to Covid-19. But when it comes to boosting your general health, it’s a no-brainer – it keeps bones, teeth and muscles healthy. And a lack of it can lead to bone deformities and pain.
Here are seven ways to get that sunshine vitamin into your life all year round.
The easiest option and one many will be doing already. You should take 10 micrograms (400 IU) of vitamin D a day between October and early March to keep your bones and muscles healthy. People with dark skin are urged to take them all year round.
Do not take more than 100 micrograms of vitamin D a day, as it could be harmful. Taking too many supplements over a prolonged period can cause a build up of calcium in the body, known as hypercalcaemia, which can weaken the bones and damage the kidneys and heart.
Online pharmacies have reported a rise in demand for vitamin D, attributed to the fact more people are spending time indoors during the third lockdown.
From late March until the end of September, most people with white skin will normally get enough vitamin D through a mixture of sunshine and a balanced diet. But in 2020, at points where lockdowns prevented people from leaving their homes as much, health officials encouraged people to continue taking vitamin D supplements – and they say the same of the third lockdown.
People with darker skin – for example, those from an African, African-Caribbean or south Asian background – may not get enough vitamin D from sunlight, according to the NHS, which is why they are urged to take a daily supplement containing 10 micrograms of vitamin D throughout the year.
People who do not spend much time outdoors, live in care homes, or who cover up most of their skin when outdoors are also advised to take a vitamin D supplement all year round.
3. Oily fish
Salmon is a great source of vitamin D. You can also find it in mackerel, tinned tuna, kippers, trout, herrings, pilchards and sardines.
Eggs are the best source of vitamin D after oily fish. This is particularly the case when the eggs come from free range hens who’ve had access to sunlight and a good diet. The vitamin D content in eggs is basically all in the yolk.
5. Red meat
Red meat such as beef and lamb contain decent amounts of vitamin D. Offal, such as cow’s liver and kidneys, also provide “considerable amounts of vitamin D”. The content in muscle meat is generally much lower, according to a study published in the journal Advances In Nutrition.
Many of the foods already mentioned are not vegan-friendly, but there are ways to get vitamin D even if you follow a plant-based diet – and mushrooms should be your number one friend.
A review on the vitamin D content of mushrooms, published in the journal Nutrients, found levels of vitamin D can decrease slightly in storage and after cooking. However, eat your mushrooms before their ‘best-before’ date and the vitamin D level is likely to remain above 10 micrograms.
“Mushrooms have the potential to be the only non-animal, unfortified food source of vitamin D that can provide a substantial amount of vitamin D in a single serve,” the authors wrote.
7. Fortified foods
There are a variety of foods in the UK which are fortified with vitamin D, these include: some cereals, margarine, infant formula milk and some yoghurts. You might be surprised to find that cereals including Coco Pops, Corn Flakes and Rice Krispies are all fortified with vitamin D.