Whether we like it or not, the weather is definitely up there as one of our most covered conversation topics. Yes, a damp afternoon or cloudy weekend can be mildly frustrating, but it turns out this crappy weather might actually have more sinister consequences than mislaid plans. We all know how the changing seasons can affect us mentally and emotionally, but a lack of sunshine is making a lot of us deficient in a key component of our body's mechanisms: vitamin D. You've probably heard people talking about the issue multiple times on the news, but let me explain once and for all why a vitamin D deficiency is such a problem (and how you can go about fixing it).
Why Do We Need Vitamin D?
Vitamin D is classically known as the “sunshine vitamin” because it’s made by the effect of sunlight on the skin. Ninety percent of vitamin D is made by the effect of sunlight, with only 10% coming from our diet, so it can be hard to maintain optimum levels. The vitamin has a wealth of health benefits, mainly because its effects are not simply confined to one body system.
One of the most vital effects of vitamin D is promoting bone health by regulating the absorption of calcium and phosphorous. Traditionally, vitamin D deficiency is associated with rickets in children and osteomalacia in adults. These diseases, in which the bone tissue doesn't properly mineralize, lead to soft bones and skeletal deformities. Vitamin D is also essential for a healthy immune system, muscle strength and health, skin health and mental health.
What Are the Symptoms of Vitamin D Deficiency?
A vitamin D deficiency can manifest in the following ways: aching bones and joints; muscle weakness; tiredness and general fatigue; flare-ups in skin conditions; poor skin healing; and recurrent infections.
What Causes Vitamin D Deficiency?
Reduced Sun Exposure: People with living in cooler climates with reduced hours of sunlight, people working indoors for prolonged hours and people who have their skin covered up outdoors are all more prone to a deficiency.
Restricted Diets: Those following a strict vegetarian or vegan diet (or a non–fish eating diet) are the most at risk.
Digestive Problems: As vitamin D is a fat-soluble vitamin, people with gut problems such as coeliac disease or inflammatory bowel disease can have problems absorbing vitamin D from dietary sources.
Increased Demand: The following groups of people are at risk of low levels of vitamin D as their baseline body requirements are higher than the average person—young children, pregnant women, breastfeeding women, and elderly people.
Skin Color: People with darker skin are naturally more at risk than people with lighter skin because the increased levels of melanin in their skin reduce their ability to make vitamin D, even in the presence of sunlight.
How Can You Test for a Vitamin D Deficiency?
Vitamin D deficiency can easily be picked up on a simple blood test that can be organized by your GP. The normal range of vitamin D is wide, so the results are interpreted as either normal, suboptimal or deficient.
Normal Levels: If your levels are normal, the key thing here is to keep them that way. This is best achieved by supplements that can be bought over the counter, along with safe sun exposure and a healthy balanced diet.
Suboptimal Levels: This means your levels are lower than the ideal level but not dramatically low enough to warrant high dose replacement therapy. In this case, your GP may prescribe a vitamin D supplement around 800 to 1000 units daily and then recheck your baseline levels in two to three months.
Deficient Levels: If your levels are lower than the normal range, they’re classed as deficient and need high-dose replacement therapy. In this case, your GP is likely to prescribe a high dose treatment of around 20,000 units, which can be prescribed over a variety of time frames—normally about two months. Once you have completed the course, your levels should be rechecked. Hopefully, your vitamin D will be back in the normal range, in which case you can commence maintenance treatment.
Can You Get More Vitamin D Through Your Diet?
Unfortunately, we can’t rely solely on our diet to receive our total vitamin D requirement—it only gives 10% at best—but the foods that contain the most vitamin D are oily fish, eggs and red meat. Some food groups are fortified with vitamin D; these include cereals, formula milk, and some dairy products.
In summary, it’s important to remember that it’s all about safe sun exposure. It’s estimated that around 20 to 30 minutes of sunlight on the face and forearms around the middle of the day two to three times a week is sufficient to make enough vitamin D in the summer months. A simple blood test is all that’s needed to detect your vitamin D levels, so if you’re showing any of the symptoms mentioned above, be sure to check in with your GP.