We all know that vitamin D is vital for healthy bones, teeth and muscles as well as a whole host of other benefits. But if you adhere to a strict vegan diet, stay out of the sun or have dark skin, you may be suffering from vitamin D deficiency - and according to experts, it's more common than we think.
The trouble with vitamin D is that the body can't create it itself, the main source of it coming from direct sunlight on the skin. And with the sun becoming public enemy number one due to its association with skin cancer, many of us are falling short in our vitamin D reserves. We chat to certified nutritionist Franziska Spritzler, founder of , to find out everything we need to know about the vital vitamin.
Why is vitamin D so important to our health?
According to Franziska, vitamin D is not only a vitamin but also a hormone. "It plays important roles in maintaining a healthy immune system and protecting against disease. It enhances calcium absorption and is crucial for maintaining strong bones," she says. As well as that, vitamin D deficiency has also been associated with infections, cardiovascular disease and autoimmune and inflammatory diseases including multiple sclerosis.
Do we get enough of it?
Although there are guidelines for the amount of vitamin D we need on a daily basis, Franziska thinks it may not be enough; "I think that the RDA [recommended daily allowance] for vitamin D (600 IU for younger people and 800 IU for older adults) isn't high enough for many individuals," she says. "Most people have insufficient or deficient levels of vitamin D in the blood."
What's the main cause of deficiency?
As well as a lack of sunshine, inadequate dietary vitamin D plays a role in vitamin D deficiency. "Fatty fish (and especially cod liver oil) is the only food that contains large amounts of this vitamin, although shellfish and egg yolks also contain some," she explains. Another contentious cause of deficiency is avoiding the sun. "Avoiding sun exposure is also a major contributor to vitamin D deficiency, and people in areas with little sunshine are at the greatest risk." Emerging scientific research is suggesting that according to our skin tone and the altitude at which we live, we should spend a number of minutes (ranging from 5 minutes for fair skin, to 20 minutes for dark skin) in the sun every day - without SPF.
But what about supplements?
I think vitamin D supplementation is important in those who have been diagnosed with vitamin D deficiency, especially if they are unable to increase their sun exposure to bring levels up to the optimal range. People who avoid the sun and those who follow strict vegan diets would also benefit from vitamin D supplementation. However, it's important to regularly monitor vitamin D blood levels when supplementing, as vitamin D toxicity can occur.