DR MICHAEL MOSLEY: I don’t believe in supplements, except for this one, which I’ve now started taking year-round.

I’m generally not a fan of taking a lot of supplements, as I think you can get most of what you need from a healthy diet.

But I make an exception for vitamin D. And with recent studies showing that high doses can not only reduce the risk of colon cancer, but also dementia, I’m now taking a higher dose than usual and taking throughout the year.

During the winter months, when the sun is weak, I have always followed the NHS advice and swallowed a daily pill, because I know that vitamin D is so important for a number of reasons.

But usually around this time of year, when the sun is strong and summer is well on its way, I stop taking it. After all, I eat a lot of fatty fish and eggs, both of which are rich in vitamin D, and I also go for a lot of walks, so my vitamin D levels should be well topped up.

However, I will continue to take these supplements this year.

This is partly because, surprise surprise, every year I get older, and studies have shown that as we age, our bodies become less effective at absorbing vitamin D from food, and our skin also becomes less efficient at converting light solar in this nutrient.

This, and the fact that older people tend to spend more time indoors or in the shade, means that vitamin D deficiency is very common in the over-60s, even in the summer months, especially if you have darker skin.

But what dose should be taken? This is where things get more controversial. While the NHS suggests you stick to 10 micrograms (mcg) or 400 international units (IU) of vitamin D a day, the US National Institutes of Health recommend 15 mcg and 20 mcg if you’re over 70.

Take 25 mcg (1,000 IU), which is within the limits of what is considered safe (anything less than 100 mcg a day for adults or 50 mcg for children, according to the NHS), but closer to the type of doses which studies show you need to take to prevent infections, cancers and maybe even dementia.

Since its discovery in the 1920s, vitamin D’s best-known role has been to maintain healthy bones by increasing the body’s absorption of calcium.

In recent years, scientists have discovered that there are vitamin D receptors in almost all of our cells, suggesting that its usefulness extends far beyond the bones.

But there is growing evidence that to enjoy benefits in these areas, such as preventing colon cancer and maintaining brain health, you need larger doses than are usually recommended.

For example, when it comes to cancer, a very recent study, published in the journal Science, showed that one of the ways that taking large doses of vitamin D might work is by increasing the type of gut bacteria that are particularly good at preventing cancer. growth of bowel cancers. When researchers at the Francis Crick Institute in London gave mice a diet rich in vitamin D, the levels of Bacteroides fragilis increased, and higher levels of this bacterium protected them better against colon cancer.

Although there is currently no clear evidence that taking high doses of vitamin D has the same impact on the human gut, there are ongoing trials to use it to treat colon cancer.

In 2017, for example, a trial of 139 patients with advanced colon cancer undergoing chemotherapy found that those taking high-dose vitamin D (100 mcg) were 36% less likely to have died or to see his disease progress. over the course of the two-year study than those on a low dose (10 mcg). Encouraged, the team is now conducting a larger, longer study looking at whether high doses of vitamin D can help slow or even prevent the spread of the disease.

Meanwhile, evidence for vitamin D’s impact on delaying dementia is also mounting.

Last year there was a fascinating study from the University of Exeter where they looked at the brains of over 12,000 people participating in the US National Alzheimer’s Coordinating Center (a project that collected data on the disease).

At the start of the study, the patients had an average age of 71 and did not have dementia, and just over a third (37%) said they took vitamin D supplements regularly. Vitamin D fans will be pleased to know that over the next ten years those who took the supplements were 40% less likely to develop dementia.

This may be because vitamin D has been shown to help prevent the build-up of two proteins in the brain, amyloid and tau, that have been linked to dementia. It also helps reduce inflammation, another trigger of dementia.

Although compelling, this was not a proper randomized controlled trial where people taking the supplement were compared to a placebo group and patients received very different doses, making these results difficult to interpret.

But the same researchers have been conducting a trial with patients at risk of developing dementia, which will include randomly assigning them to either a high-dose vitamin D supplement (100 mcg) or a placebo. I will let you know when the results are released.

In the meantime, take a supplement if you need it (obviously ask your doctor about the right dosage, especially if you have existing health conditions), and make the most of the vitamin D boost you get during the summer months by spending at least ten minutes up to date with the sleeves rolled up.

Taking the stairs can help your heart

When I’m at an airport or mall I’m always surprised (and disappointed) by how many people are on the escalators, even when they’re going down.

All I can say is that you are missing out on an opportunity to give your heart a good workout and potentially extend your life. This was the conclusion of a recent review presented at a conference of the European Society of Cardiology.

Based on data from 480,000 people, it found that regular stair climbers were 39% less likely to die from a heart attack or stroke and 24% less likely to die from any cause. This is because it is a relatively intense exercise that gets the heart racing quickly.

Taking the stairs is even more beneficial In a 2017 study from Edith Cowan University in Australia, overweight women either took an elevator to the sixth floor and then walked back down, or took the elevator up and down twice a week . After a fortnight, those who went down saw the biggest benefits in balance, bone strength and blood pressure probably because going down the stairs makes the muscles have to work harder to keep from falling.

What to do with this persistent cough

You may have noticed, there is an annoying and persistent cough. I got it a couple of weeks ago from my brother-in-law, who had it for at least three weeks, who in turn got it from his wife.

This one keeps me up at night and shows no sign of improvement. The problem is that I don’t really believe in the effectiveness of over the counter remedies (there is no adequate evidence that cough medicines work), but in desperation I resorted to cough syrup and a zinc supplement. Neither has done anything good so far. I was particularly disappointed with zinc, as studies have suggested that supplements can shorten a cold and reduce cough by up to 46 percent. (Though that only seems to apply if you take them within 24 hours of developing symptoms, so I’ve probably missed the boat on that one.)

If you have a similar cough, I suggest drinking plenty of water and occasionally warm lemon and honey (honey helps soothe the throat, while lemon has anti-inflammatory properties). The NHS says to see your doctor if your cough persists for more than three weeks.

Put a thief to catch a thief is a well-known saying that, fortunately for us, seems to apply to bacteria as well. A new study from the University of Bonn in Germany found that a common type of skin bacteria, Staphylococcus, kills other bacteria by injecting a chemical that dissolves their cell membranes.

The idea is that this could be used to create a new antibiotic, which is exciting given that many bacteria are now resistant to antibiotics, including the first truly effective antibiotic, penicillin, which saved my life as a baby when I caught pneumonia