Overall, I’m not a fan of taking a lot of supplements because I think you can get most of what you need from a healthy diet.
But I make an exception for vitamin D. And because recent studies show that high doses can reduce the risk not only of colon cancer, but also of dementia, I now take a higher dose than normal – and I use it. throughout the year.
During the winter months, when the sun is weak, I have always followed the NHS advice and taken a daily tablet, as I know vitamin D is so important for a whole host of reasons.
But usually around this time of year, when the sun is strong and summer is approaching, I stop. After all, I eat a lot of oily fish and eggs, both rich in vitamin D, and I also go outside a lot, so my vitamin D levels must be good.
However, this year I will continue to take these supplements.
Research shows that as we age, our bodies become less effective at absorbing vitamin D from food and sunlight. That’s why Dr. Michael Mosley says he takes supplements year-round.
That’s partly because, surprisingly, I’m getting older every year 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 sunlight into this nutrient.
That, and the fact that older people tend to spend more time indoors or in the shade, means that vitamin D deficiency among the over 60s is very common, even in the summer months, especially if you have darker skin.
But what dose should you take? That’s where things get more controversial. While the NHS suggests you should stick to 10 micrograms (mcg) – or 400 international units (IU) of vitamin D per day, the National Institutes of Health in the US recommends 15 mcg – and 20 mcg if you’re over 70.
I take 25 mcg (1,000 IU), which is within the range of what’s considered safe (anything under 100 mcg per day for adults or 50 mcg for children, according to the NHS), but closer to the kind of doses shown in studies turns out you need to take it to prevent infections, cancer and maybe even dementia.
Since its discovery in the 1920s, vitamin D’s best-known role has been in keeping your bones healthy by increasing the body’s absorption of calcium.
In recent years, scientists have discovered that vitamin D receptors are present in almost all of our cells, suggesting that its usefulness extends far beyond the bones.
But there is mounting evidence that to reap the benefits in these areas, such as preventing colon cancer and maintaining brain health, you need larger doses than routinely recommended.
When it comes to cancer, for example, a very recent study published in the journal Science found that one of the ways that taking large doses of vitamin D could work is by boosting the kind of gut bacteria that are particularly good at prevention of growth. of colon cancer. When researchers at the Francis Crick Institute in London fed mice a diet rich in vitamin D, it increased the levels of Bacteroides fragilis – and higher levels of this bacteria better protected them 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, studies are underway into its use to treat colon cancer.
For example, in 2017, a study of 139 patients with advanced colon cancer undergoing chemotherapy found that those who received high-dose vitamin D (100 mcg) were 36 percent less likely to die or see their disease progress. over the course of the two-year study than that with a low dose (10 mcg). Encouraged, the team is conducting a larger, longer study to investigate whether high doses of vitamin D can help slow or even prevent the spread of the disease.
Meanwhile, evidence is mounting for vitamin D’s impact on slowing dementia.
Last year there was a fascinating study from the University of Exeter that looked at the brains of more than 12,000 people participating in the US National Alzheimer’s Coordinating Center (a project that collects data on the disease).
At the start of the study, patients were on average 71 years old and free of dementia – and just over a third (37 percent) said they regularly took vitamin D supplements. Vitamin D fans will be happy to hear that those who took the supplements were 40 percent less likely to develop dementia over the next decade.
This may be because vitamin D has been shown to help prevent the buildup of two proteins in the brain, amyloid and tau, that have been linked to dementia. It also helps reduce inflammation, another trigger for dementia.
Although compelling, this was not a true randomized controlled trial – comparing people taking the supplement to a placebo group – and the patients all received very different doses, making these results difficult to interpret.
But the same researchers conducted a trial of patients at risk of developing dementia, randomly assigning them to a high-dose vitamin D supplement (100 mcg) or a placebo. I’ll let you know when the results are known.
In the meantime, take a supplement if you need it (of course, ask your doctor for the right dose, especially if you have existing health conditions) and take full advantage of the vitamin D boost you get in the summer months by taking at least ten minutes a day outside — with sleeves rolled up.
Climbing stairs can help your heart
When I’m at an airport or a mall, I’m always surprised (and disappointed) at how many people are on the escalator, even when it’s going down.
All I can say is that you are missing the opportunity to give your heart a good workout and possibly extend your life. That was the conclusion of a recent study presented at a conference of the European Society of Cardiology.
Based on data from 480,000 people, it was found that those who regularly climb stairs were 39 percent less likely to die from a heart attack or stroke, and 24 percent less likely to die from any cause. This is because it is a relatively intensive exercise that gets your heart beating faster.
It’s even more beneficial to walk down the stairs: In a 2017 study from Edith Cowan University in Australia, overweight women either took the elevator to the sixth floor and then walked down, or walked up twice a week and took the elevator down. After a fortnight, those who walked down stairs saw the biggest benefits in balance, bone strength and blood pressure – probably because walking down stairs means your muscles have to work harder to prevent you from falling.
What to do about that persistent cough
You may have noticed an annoying, persistent cough going around. I got it a few weeks ago from my brother-in-law, who had had it for at least three weeks, and who in turn got it from his wife.
This one keeps me awake at night and shows no signs of improvement. The problem is that I don’t really believe in the effectiveness of over-the-counter medicines (there’s no good evidence that cough medicines work), but out of desperation I resorted to cough syrup and a zinc supplement. Neither has done anything good so far. I was especially disappointed with the zinc, because research has shown that supplements can shorten the duration of a cold and reduce coughing by up to 46 percent. (Although that only seems to apply if you take them within 24 hours of developing symptoms, so I probably missed that boat.)
If you experience a similar cough, I recommend drinking plenty of water and occasionally hot lemon and honey (honey helps soothe the throat, while lemon has anti-inflammatory properties). The NHS says you should see your doctor if the cough lasts for more than three weeks.
Use a thief to catch a thief is a well-known saying that, fortunately for us, also seems to apply to bacteria. A new study from the University of Bonn in Germany has 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 can be harnessed to create a new antibiotic, which is exciting considering that many bacteria are now resistant to antibiotics – including the first truly effective antibiotic, penicillin, which saved my life as a baby when I had a got pneumonia.