The sun has enjoyed a bright career being worshipped as deity to our ancestors and bringer of health. In recent years however, it has taken some heat for the danger that overexposure can have on the skin, resulting in advice to cover up and use sunscreen. But with the covid-19 outbreak prompting many to look for ways to improve their health and resilience, once again it’s time to shine, and the hot topic of the day is vitamin D.
It has long been known to regulate calcium levels in the body and keep our bones, muscles and teeth healthy. The current interest in Vitamin D though, lies in the vital role it plays in boosting our immunity. It does this by regulating our immune systems to the responsiveness of infections. It’s known to be one of the most critical factors in our resistance to diseases such as tuberculosis. It may help the body’s resistance to pathogens too, and deficiency has been shown to lead to poor response to infections, allergies and autoimmune disease. New research even links a lack of vitamin D to the development of bowel disease, MS, arthritis and lupus.
This is why it has been suggested that it may help reduce the risk of infection from coronavirus. But even when things return to normal there are many reasons to stay topped up with this vital vitamin. For one it may extend our lives. A large-scale study of 95,000 adults even showed that administering vitamin D led to fewer deaths overall. How D-lightful.
For those in high-risk categories, having enough vitamin D might be even more important than usual. For example, several studies have shown that it plays a role in asthma prevention. Even before birth, mothers who supplemented it during pregnancy produced children who suffered fewer respiratory infections during early childhood. Continuing the journey, 6-year-olds with low levels of the vitamin were more likely to develop bronchial asthma aged 14. And the benefits extend throughout life, with one study showing that giving adults with mild to moderate asthma vitamin D supplements significantly reduced the severity of their attacks.
Another high-risk category at the minute is diabetes. Vitamin D can support diabetics, as it has been shown to improve insulin sensitivity and encourage weight loss. Diabetes UK recommends it for controlling blood glucose levels. Furthermore, a Norwegian study of 92,000 pregnant women found that those with low levels of Vitamin D doubled the risk of their children developing type-I diabetes.
As you probably know, Vitamin D is produced naturally when the sun shines on our skin. As many of us are stuck indoors for longer than usual right now, we might not be getting as much sunshine as we should. But even if you’re lucky enough to have a garden to lie outside in and the weather to make the most of it, there’s a good chance you’re not getting enough of the good stuff. That’s because, if you live above 37 ° latitude (that’s everyone north of the Mediterranean), the sun’s UVA rays are insufficient for year-round vitamin D synthesis, lockdown or not.
Many other factors also prevent absorption, such as time of day, cloud cover, air pollution, age, clothing, and even skin tone. In fact people with darker skin are more at risk of vitamin D deficiency, as the increased melanin, whilst limiting sunburn by reducing the absorption of UVA, also means you’ll need longer exposure to sunlight to give the same results.
So if the sun isn’t enough, what else can we substitute it for? Some foods contain vitamin D, notably oily fish, eggs and organ meat, but generally only in small quantities. For example you’d need to eat three whole wild salmon or 20 eggs to get your recommended daily amount.
If you’re following a plant-based diet your choices are even more limited. Wild mushrooms are one of the rare exceptions, but they contain only the less well absorbed D2, and commercially grown mushrooms are raised in the dark and don’t contain any. For vegan-friendly Vitamin D3, the better-absorbed type, you’ll need to start nibbling mosses, lichen and seaweed. If you don’t have access to remote highland forests, or don’t feel like jostling lobsters for the best pickings of kelp then fear not, there are supplements out there that do the hard work for you.
There are many brands of Vitamin D supplements out there, though few are vegan. Most are made by irradiating the oils in sheep skin but there are some also some great vegan brands like Protea Wellness that produce high-quality D3 from plant sources. As always, consult your doctor before starting any high-dose supplements, especially if you’re in high-risk categories.