With the winter months in full swing, many people are paying closer attention to their health, but according to medical experts, there may be one simple step most of us are overlooking. Dr. Shireen, a general practitioner with the UK’s National Health Service (NHS), has been urging people to add a specific supplement to their daily routine, stressing that it can play a vital role in keeping the body functioning well during colder months. She shared her advice in a video that quickly caught attention, laying out the case for why this one nutrient deserves a spot in everyone’s medicine cabinet. Her recommendation is straightforward and backed by official health guidelines.
“I am an NHS GP and today I am going to tell you about one supplement that everyone should be taking right now. When you are deficient in this vitamin, it is often not obvious,” Dr. Shireen explained. She went on to describe a range of subtle warning signs that many people might brush off as everyday tiredness or seasonal sluggishness. “Symptoms come on very subtly. For example, fatigue, body aches, a general feeling of exhaustion, more frequent colds and coughs than usual, and perhaps mild hair loss. This is vitamin D deficiency,” she said. These are symptoms that countless people experience during winter without ever connecting them to a nutritional gap.
One of the most common misconceptions is that a reasonably healthy diet provides enough vitamin D, but Dr. Shireen pushes back on that idea firmly. “We are always taught as doctors to advise diet first, which is fine if we live very unencumbered lives and are able to eat everything we want. But even with the best diet in the world, you will never get enough vitamin D from food alone,” she said. The body primarily relies on sun exposure to produce this vitamin, and during the winter season that simply is not happening at the levels needed to keep stores topped up. “We need to supplement it because we mostly get it from the sun and sunlight. Obviously right now, during the winter months, we are not seeing enough sun to be able to maintain the vitamin D levels we need,” Dr. Shireen added.
Her recommendation is to take around 800 to 1,000 IU (international units) of vitamin D daily from October through March, and throughout the entire year for anyone who spends most of their time indoors. While she encourages people to get their levels tested if possible, she makes clear that supplementation is advisable for virtually everyone in the colder half of the year. Official NHS guidance aligns with her advice, noting that everyone should consider taking a daily vitamin D supplement during autumn and winter. The guidelines also specify that people at high risk of deficiency, all children between one and four years old, and all babies unless they are drinking more than about 17 ounces of formula per day, should take a supplement year-round.
According to the NHS, the situation changes between late March or early April and the end of September, when most people can get all the vitamin D they need through sunlight on their skin combined with a balanced diet. “Between late March or early April until the end of September, most people can get all the vitamin D they need through sunlight on the skin and a balanced diet. You may choose not to take a vitamin D supplement during these months,” the official guidance states. Dr. Shireen emphasizes that for anyone concerned about taking supplements, a quick conversation with their own doctor before making any changes is always the wisest course of action.
Vitamin D is a fat-soluble nutrient that the human body produces naturally when skin is exposed to ultraviolet B (UVB) rays from sunlight, which is why it is sometimes called the “sunshine vitamin.” It plays a critical role in helping the body absorb calcium and phosphorus, which are essential for building and maintaining strong bones and teeth. Beyond bone health, vitamin D supports muscle function and is closely linked to immune system regulation, which is part of why deficiency is associated with a higher susceptibility to infections. Foods that contain vitamin D include fatty fish such as salmon and mackerel, egg yolks, and fortified products like certain dairy items and cereals, though as Dr. Shireen points out, dietary sources alone are generally not sufficient. Severe vitamin D deficiency can lead to rickets in children, a condition that causes bone deformities and stunted growth, while in adults it can cause osteomalacia, which results in soft, weakened bones and significant pain.
If you have experienced any of the subtle symptoms Dr. Shireen described or have questions about your own vitamin D levels, share your thoughts and experiences in the comments.
