Woman looking at supplements by a countertop

Vitamin D helps us feel happy, healthy – and, crucially, boosts our immunity. Sarah Maber gets the lowdown.

Autumn is the time of year when we traditionally start to hibernate. Sleeveless tops and shorts are replaced by coats, tights and jumpers, and we spend less time outside as the nights draw in. And while there are many things to celebrate about autumn – hot chocolate, log fires and Strictly among them – our seasonal hibernation, and the UK’s weak winter sunshine, means that our levels of vitamin D nosedive.

One in five of us suffers from low levels of the vitamin and post-winter, this increases to one in three, according to immunity expert Professor Steve Jones. ‘April is normally the month when vitamin D deficiency is at its peak,’ he says, ‘because we’ve just come out of winter, when our vitamin D stores have been depleted. In April, one in three people in southern England will be below the safe limit for vitamin D.’

Why does this matter? Well, vitamin D is no ordinary nutrient. ‘Vitamin D is created when we expose our skin to sunlight, and it is also found in some foods,’ says nutritional therapist Eve Kalinik. ‘It is a bit of a misnomer to label it a vitamin because it acts more like a hormone in the body, with a crucial role in maintaining strong and healthy bones, supporting the immune system and for cardiovascular health.’

According to Professor Jone the vitamin controls many of the body’s functions: from the lungs to the heart to the brain, he says, ‘you’ll find vitamin D hard at work.’ Studies show that it protects against some cancers and cardiovascular disease, and fights depression and fatigue. But it’s as an immunity booster that this ‘sunshine’ vitamin has attracted recent attention. ‘Vitamin D activates our immune defences, which is important as we move into the colder months,’ says nutritionist Rob Hobson. And while there is no direct evidence, some experts believe it may help protect us against coronavirus as low levels of the vitamin have been linked to respiratory conditions. 

Vitamin D might even help you shift that lockdown stone as there is some evidence that vitamin D boosts weight loss. In one study, people taking a daily calcium and vitamin D supplement were able to lose more weight than those taking a placebo; researchers suggested that the extra calcium and vitamin D had an appetite-suppressing effect. So as we move into the colder, shorter days of autumn and winter, here’s how to make sure you’re getting enough of the sunshine vitamin.

Take supplements. 

‘Sunlight is the best way to absorb vitamin D, but the sun really isn’t strong enough in the winter months,’ says Rob Hobson, ‘and you just can’t get enough… from your diet. Everyone should supplement with the recommended amount suggested by Public Health England – 10mcg daily. It comes in various forms – gummies, tablets and sprays. Choose vitamin D3 as opposed to D2, as that’s the most easily absorbed by your body.’ A recent study showed oral sprays and tablets are equally effective – and if you do supplement, take it with your main meal of the day. Vitamin D is fat soluble, and main meals tend to have more fat. 

Eat food rich in it. 

Top up with foods containing vitamin D like salmon, tuna, mackerel, milk, some cereals and eggs, plus lots of fortified foods; you can also buy mushrooms that have been treated with UV light to boost their vitamin D content (or try leaving regular mushrooms on a sunny windowsill to increase their vitamin D supply). Vitamin D can be stored, so any excess you take in will be used by the body on days when you don’t get enough. 

Get outside.

While winter sunshine might not be strong enough to directly impact our levels of the vitamin, there are other reasons to spend time in the sun. Research by Richard Weller, a consultant dermatologist and senior lecturer at the University of Edinburgh, suggests that as well as being anti-inflammatory and mood-boosting, sunlight may also lower blood pressure. Sunlight also helps set and synchronise our body clocks, so if you’re struggling to sleep, try heading outside into natural light when you wake.

To help you out as the cold approaches, check out our 7 health tricks you need to feel happier this winter.

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