6 benefits of vitamin D from slowing down ageing to boosting immunity

Taking regular vitamin D supplements could slow down biological ageing, according to a new study.

The trial, published by the American Journal of Clinical Nutrition, found that not only did those taking the vitamin every day see less age-related damage to their DNA, the supplement could “prevent the equivalent of nearly three years of ageing” when taken over the course of four years.

Vitamin D supplements are said by the authors of the study to be a “promising strategy to counter biological ageing”, that could also help lower the risk of various diseases, such as Alzheimer’s, dementia and some cancers.

Here, we take a look at the other benefits and potential side-effects of vitamin D, which is made naturally by our bodies in sunlight, and found in a small number of foods such as oily fish, red meat, egg yolks, liver and fortified cereal as well as supplements.

Five other benefits of vitamin D

1. It helps keep bones, teeth and muscles healthy

Not only does vitamin D help with bone development and maintenance, it regulates the body’s calcium and phosphate levels, making sure you get enough nutrients to keep your bones, teeth and muscles healthy.

Too much calcium (also known as hypercalcemia) can cause stomach upset, vomiting and constipation – while too little (hypocalcemia) can cause spasms, muscle cramps, numbness in the hands, arms, feet and legs. Over time, a calcium deficiency can lead to brittle bones, dry skin, broken or brittle nails and coarse hair, among other things.

Phosphate, meanwhile, helps maintain the integrity of cell membrane, promotes bone and teeth growth and health, and is essential for the production of energy, muscle and nerve function.

2. It may improve heart health

A 2015 study part-funded by the British Heart Foundation found that having low levels of vitamin D could be associated with an increased risk of cardiovascular disease. Though, it points out, low vitamin D is a result of lifestyle factors, rather than the cause of increased risk.

Too much vitamin D, however, can have an adverse affect on the heart, as high levels of calcium can cause heart palpitations, hypercalcemia (as mentioned above) and even increase the risk of coronary artery disease (CAD) – which, in turn, may lead to a heart attack or congestive heart failure.

3. It boosts the immune system

Those with low levels of vitamin D have been shown to be more susceptible to autoimmune and infectious diseases, like rheumatoid arthritis, multiple sclerosis (MS) and type 1 diabetes.

4. There’s a link between vitamin D and body weight

A 2021 medical review, looking at various studies that suggest low vitamin D is associated with obesity, found there is a link between vitamin D levels and body weight. However it said interventional studies do not support a beneficial effect of vitamin D supplementation on body weight and that more evidence is needed to suggest a casual link between the vitamin and weight management.

5. It may also have mood-boosting qualities

According to a paper published in 2022, low vitamin D levels are associated with increased depressive symptoms, as well as anxiety. It went on to say that, because of its antioxidant properties and activity in brain tissue, vitamin D is important in the treatment and prevention of mood disorders.

How often should I take vitamin D supplements and do I need to take them in the summer?

The official guidelines provided by the UK government state that everyone should aim to have a daily vitamin D supplement during the autumn and winter.

As the sun is a source of vitamin D, most of us don’t need to take supplements in the warmer months. However, official advice is that for those at risk of not getting enough vitamin D – such as children aged 1-4 and babies – should take a daily supplement all year round.

Signs of a vitamin D deficiency include fatigue, muscle ache, bone and lower back pain and hair loss, among other things. Severe deficiency of vitamin D can also result in rickets in children and osteomalacia in adults. You can find out more here.

Other sources of vitamin D

• sunlight

• oily fish (like salmon, sardines, herring and mackerel)

• red meat

• liver

• egg yolks

• fortified foods (like some fat spreads and breakfast cereals)

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