Vitamin D through the winter is worth the pennies. Magnesium and omega-3 capsules are a harder sell for most men. Here’s what the evidence and the NHS actually say.
Walk into any high street chemist and you’ll find a whole wall promising better sleep, a sharper brain and a heart like a 30-year-old’s. The trouble is that a fair bit of what sits on those shelves gives you very expensive urine and not much else.
So let’s look at the three supplements men in midlife ask about most: vitamin D, magnesium and omega-3. One of them is backed by official UK advice. The other two are mostly about your shopping list rather than your pill box.
For most of us, yes. This is the easy one.
Your skin makes vitamin D when sunlight hits it. In the UK, the sun is only strong enough for that from about late March or early April to the end of September. Outside those months your skin doesn’t make much at all, however long you stand in the car park looking hopeful.
So the NHS advises everyone to consider taking 10 micrograms of vitamin D a day in autumn and winter, roughly October to March. On the label, 10 micrograms may also be written as 400 IU (international units). The advice is the same across the UK: the Scottish Government, for example, recommends that everyone aged 5 and over considers a daily 10 microgram supplement, especially in the winter months.
Some people should think about taking it all year round. That includes you if you rarely get outside, if you usually cover most of your skin when you’re out, or if you have dark skin, such as an African, African-Caribbean or South Asian background, because your skin makes less vitamin D from sunlight.
Why bother? Vitamin D helps your body control calcium and phosphate, which you need for healthy bones, teeth and muscles. Let it run low for long enough and you’re heading for bone pain and weakness. That matters more with every birthday, as bone and muscle mass slowly drop away in midlife.
What vitamin D won’t do is turn you into a superhero. Large trials, including the big American VITAL study, found that people who took vitamin D on top of a normal diet didn’t see a clear drop in cancer or heart disease. Take it for your bones and muscles, not as a cure-all.
It’s also cheap. A basic own-brand 10 microgram tablet costs pennies a day, so you don’t need the premium bottle with the mountain photo on the front.
Yes, and this is where some people go wrong. More is not better. The NHS advises adults not to take more than 100 micrograms (4,000 IU) a day. Taken in large amounts for a long time, vitamin D can cause too much calcium to build up in the body, which can weaken bones and damage the kidneys and heart.
Watch out for high-strength products. Some combine vitamin D with other things, and if you also take a multivitamin you can end up doubling your dose without noticing. Add up what’s on the labels.
If your GP has diagnosed a deficiency and prescribed a higher dose, that’s a different matter. Follow their advice rather than the general guidance.
Vitamin D from October to March is the one supplement most British men should actually buy. Most of the rest belongs on your plate, not in a capsule.
Magnesium has had a brilliant few years on social media. It’s sold for sleep, cramp, stress, muscle recovery and more or less everything else.
The basics are dull but true. Magnesium helps turn food into energy and helps your parathyroid glands work, and those glands matter for bone health. The NHS says men aged 19 to 64 need about 300mg a day. Most people can get that from their food: green leafy vegetables such as spinach, nuts, wholemeal bread, brown rice and other wholegrains.
As for sleep, the evidence is weak. Small studies, many of them in older people who may have been low in magnesium to start with, point to modest effects at best. That isn’t strong enough to call magnesium a sleep treatment. If you’re lying awake at 3am every night, your GP and the NHS advice on insomnia are better places to start than a tub of magnesium glycinate.
If you still want to try it, the NHS says taking 400mg or less a day from supplements is unlikely to cause harm. Higher doses can cause diarrhoea, which won’t do much for your sleep either. Magnesium can also interfere with some medicines, including certain antibiotics and some osteoporosis drugs, so check with a pharmacist before you add it.
For most men, the money is better spent at the fishmonger.
Omega-3 fats from oily fish are good for you, and the NHS advises at least two portions of fish a week, one of them oily. A portion is about 140g. Salmon, mackerel, sardines, trout, herring and pilchards all count, and a tin of sardines on toast is about as cheap a heart-friendly lunch as you’ll find.
Capsules are a different story. When researchers pooled the big trials, including a large Cochrane review, they found that omega-3 supplements had little or no effect on heart attacks, strokes or deaths from heart disease. NICE doesn’t recommend omega-3 supplements for preventing heart disease, and the British Heart Foundation’s line is that eating fish is the better route.
There’s also a catch. Some trials of higher-dose fish oil have found a small increase in the risk of atrial fibrillation, an irregular heart rhythm. Fish oil can also add to the effect of blood-thinning medicines. If you take any heart medication, speak to your pharmacist or GP before you start.
There are exceptions. A prescription omega-3 product is sometimes used for specific conditions, such as very high triglycerides. That is a decision for your doctor, not the supplement aisle. And if you really don’t eat fish, it’s reasonable to ask a pharmacist whether a supplement makes sense for you.
A quick rule of thumb: if you eat a reasonably varied diet, you probably don’t need much else. Water-soluble vitamins such as vitamin C and most B vitamins aren’t stored in large amounts, so the excess largely leaves you when you go to the loo. Hence the expensive urine.
Some supplements can do more harm than good. High-dose beta-carotene, for instance, has been linked to a higher risk of lung cancer in smokers. Natural doesn’t always mean safe.
If you’re worried about your diet, your weight or your heart, the free NHS Health Check is a far better investment than a cupboard of capsules. It’s offered to adults aged 40 to 74 in England every five years. Scotland, Wales and Northern Ireland don’t run the same programme, so if you live there, ask your GP practice about a check-up. For urgent worries call NHS 111, and in an emergency call 999.
Take 10 micrograms (400 IU) of vitamin D a day from October to March, or all year if you rarely get outdoors or have dark skin, and don’t go above 100 micrograms a day. Magnesium and omega-3 are best got from food, such as nuts, greens, wholegrains and two portions of fish a week, because the evidence for the capsules is weak. If you take any regular medicine, check with a pharmacist before you add a supplement.
Vitamin D in winter and creatine for your muscles have decent evidence behind them. Plenty of what’s on the pharmacy shelf doesn’t. Here’s how to spend your money sensibly.
Low vitamin D is common in UK winters and is often blamed for tiredness in midlife. Here’s what the NHS recommends, what the evidence says and when to see your GP.
Winter was heavy on the port and light on the walks. Here is what actually helps your liver recover, and why you don’t need any of the detox kit.
Midlife energy slumps usually come down to how you sleep, eat and move. Here’s how to plan a day that keeps you going, and when tiredness needs a GP.
Newsletter
The best guides of the week — collected, without the noise, for anyone who likes to stay a step ahead.
