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<\/p>\nAs winter rumbles on, most of us are going to great lengths to keep colds and flu at bay. Now there\u2019s new evidence that taking a simple, and cheap, vitamin D supplement could be the solution. This week researchers from the universities of Surrey, Oxford and Reading, analysing data on 36,000 British adults, found those with a severe vitamin D deficiency were 33 per cent more likely to be admitted to hospital with a respiratory tract infection than those getting the right amount.<\/p>\n
Unfortunately, many of us don\u2019t. According to the Department of Health and Social Care, about one in six of us have low levels of vitamin D, with a deficiency more likely in winter months when we don\u2019t get enough sunlight for our skin to produce it naturally.<\/p>\n
\u201cVitamin D is vital to our physical wellbeing,\u201d said Abi Bournot, the study\u2019s lead author from the University of Surrey. And it\u2019s not only integral to a healthy immune system. Boosting levels can have myriad other benefits for body and mind.<\/p>\n
It can reduce the risk of colds, flu and Covid<\/p>\n
Nicola Shubrook is the founder of Urban Wellness<\/p>\n
CASSANDRA LANE<\/p>\n
Vitamin D functions as a messenger in a similar way to hormones, says Nicola Shubrook, nutritional therapist and founder of the functional medicine clinic Urban Wellness. \u201cIt gets activated by the liver and kidneys into calcitriol \u2014 its active form \u2014 which can regulate hundreds of genes in many tissues, similar to oestrogen or cortisol.\u201d <\/p>\n
It activates VDRs (vitamin D receptors) located throughout our body, including in the heart, bones and lungs. When activated, VDRs have been shown to boost production of antimicrobial proteins that help to fight infection. The vitamin also improves the function of immune cells such as macrophages that help to fight viruses and calm excess inflammation that can worsen symptoms of a cold. <\/p>\n
\u201cHuman trials show a daily low dose can help to support a healthy immune response,\u201d Shubrook says. A 2022 meta-analysis in the journal Frontiers in Nutrition found those taking a vitamin D supplement were 22 per cent less likely to develop flu than those who didn\u2019t, while other studies have linked vitamin D deficiency to increased risk of severe Covid.<\/p>\n
\u2022 Can vitamin D slow ageing? Here\u2019s why I take it<\/a><\/p>\n Take (at least) a 10mcg supplement every day \u2014 it doesn\u2019t need to be an expensive brand<\/p>\n The NHS recommends everyone take a supplement of 10mcg (400IU) a day between October and March. But we all require different amounts, Shubrook says. \u201cThe darker your skin, the harder it is to make vitamin D naturally from sunshine. You can supplement and still have low levels.\u201d <\/p>\n Symptoms of deficiency can include muscle pain and low mood, but the only way to find out if you\u2019re deficient is with a blood test, which should be available through your GP but can also be paid for privately using an at-home finger prick test. The NHS defines deficiency as below 25nmol\/l (nanomoles per litre) of calcidiol \u2014 the stored form of vitamin D \u2014 in your blood, while a level of 50nmol\/l is adequate. For those deficient, 25mcg (1,000IU) supplements are widely available. The safe upper limit for most adults and children over 11 is 100mcg (4,000IU) a day, according to the NHS. The main (rare) side effect from taking too much is a build-up of calcium in the blood \u2014 hypercalcemia \u2014 which can cause symptoms such as vomiting and kidney stones.<\/p>\n In addition to pills, sprays and drops to put under the tongue are available (BetterYou Vitamin D 3000IU (75mcg) Daily Oral Spray, \u00a310.40, boots.com<\/a>). Evidence suggests they are all equally effective, but as a fat-soluble vitamin \u201cany vitamin D supplement is best taken with a meal containing fat for optimal absorption,\u201d Shubrook says. She sees no merit in buying an expensive supplement. \u201cI use a fairly cheap brand.\u201d Superdrug\u2019s 25mcg tablets are \u00a33.99 for 90; Boots\u2019 own-brand tub of 180 10mcg tablets is \u00a34. <\/p>\n \u2022 Read more expert advice on healthy living, fitness and wellbeing<\/a><\/p>\n Take it with calcium for stronger bones Vitamin D, found in oily fish like salmon, helps your body to absorb calcium from food<\/p>\n GETTY IMAGES<\/p>\n Vitamin D \u201chelps improve the absorption of calcium from food in the gut, then transport it to the bones, where it helps form cells called osteoblasts\u201d, Shubrook says. However, some evidence finds it only effective in strengthening bones when taken with a calcium supplement \u2014 a meta-analysis in the journal JAMA Network found that daily supplementation of 10-20mcg of vitamin D taken with 1,000-1,200mg calcium led to a 16 per cent reduced risk of hip fracture (Vitabiotic Ultra Calcium tablets combine 20mcg vitamin D with 1,000mg calcium, \u00a33.65 for 30, vitabiotics.com<\/a>). <\/p>\n Shubrook suggests the elderly and those at risk of heart disease also take a vitamin K supplement with vitamin D, which prevents calcium from accumulating in blood vessel walls, keeping them flexible.<\/p>\n![\"Pan-fried](\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/01\/\/38eaea6a-15bc-49d0-8a22-d0bc5a32d87c.jpg\")
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