Vitamin D is a vital supplement taken by millions across the UK to ward off diabetes, cancer and even Covid… or is it simply a useless waste of money?
Last week, in a special report, The Mail on Sunday interviewed top researchers who insisted that despite the NHS spending a whopping £8 million a month on the pills, there was next to no evidence they did anything at all for our health.
Epidemiologist Professor Tim Spector, co-creator of the Zoe Covid Study tracker app, went as far as to brand them ‘pointless’.
Vitamin D is made naturally by the skin in response to sunlight, and is essential for bone health. It is also found in fish and red meat.
NHS guidelines suggest we all take a Vitamin D supplement throughout winter, when there’s less sunshine, but Prof Spector and others were adamant this wasn’t necessary.
They also pointed out that although many clinical trials have been carried out using Vitamin D to treat and prevent illnesses, not a single one had shown any benefit.
An open and shut case? We asked readers to tell us what they thought after their own experiences with taking Vitamin D, and we were deluged with responses.
Vitamin D is a vital supplement taken by millions across the UK to ward off diabetes, cancer and even Covid… or is it simply a useless waste of money?
The vast majority couldn’t have disagreed more with Prof Spector. Many claimed that daily Vitamin D had helped combat everything from debilitating joint pain to bone problems and even mental illness.
One was reader Janet Byrne, who has polymyalgia rheumatica – an inflammatory disorder that causes muscle pain and stiffness.
‘Three weeks after taking the supplement I felt very much better physically and my depression lifted, so I have been taking it ever since,’ she wrote.
One benefit appeared to be the most common – a reduction in pain related to the weak bone condition, osteoporosis. Vitamin D helps bone tissue absorb calcium from food, which is crucial for strength and growing new bone.
One size does not fit all – it is a necessity that I take Vitamin D
Wendy Jeffries, 75, from Lincolnshire, said: ‘I have osteoporosis, and on the advice of my specialist I’ve been taking calcium and Vitamin D supplements for three years. I also take prescription medication for osteoporosis.
‘Since I’ve been taking the vitamins, tests have shown that my bone density has begun to increase again. One size does not fit all – it is a necessity that I take Vitamin D.’
Meanwhile, 54-year-old Katie Woodiss-Field, a credit manager from Oxfordshire, says that thanks to a sizeable daily dose of Vitamin D, in just three months she went from being too stiff to get out of bed to enjoying five-mile hikes.
She says: ‘During lockdown I developed horribly aching legs. They felt as if they’d lost all strength. My GP suspected a side effect of the menopause, but blood tests showed I had extremely low levels of Vitamin D.
‘I was prescribed the highest dose you can get over the counter, and I saw an improvement within a few days. It was suddenly much easier to walk up the road to the shops.
‘And then one day, about three months later, the ache just disappeared. It was like when you have a headache for a week and then you wake up and it’s gone.’
Epidemiologist Professor Tim Spector, co-creator of the Zoe Covid Study tracker app, went as far as to brand Vitamin D supplements ‘pointless’
Katie has been taking the same daily dose ever since, adding: ‘My husband often gets sore knees from exercising a lot, and when he saw the change in me, he started taking the same dose. He’s seen a big change in his mobility, too.’
We reported that studies looking at the benefits of taking a supplement for bone and joint health had shown mixed results.
In 2018, an analysis of the results of 81 previous trials concluded that Vitamin D supplements did nothing to prevent fractures or strengthen bones in those with osteoporosis.
A 2011 US study where menopausal women took Vitamin D found it had no significant effect on menopause-related joint pain, although the authors noted that some patients with severely low Vitamin D did see a mild benefit.
Other studies have shown that for people who are deficient in Vitamin D, a supplement increases the turnover of bone cells and boosts the stiffness and thickness of bones.
Many Mail on Sunday readers are also convinced of the benefits of Vitamin D on their immune system in helping to fight off infections – including Covid.
Jean Stables, from Buckinghamshire, has taken a daily dose for several years after blood tests showed she was deficient. She said: ‘Before vaccination, what was it that saved me from getting Covid? Probably Vitamin D.’
Meanwhile, David Bentley, from Leicester, said: ‘In the winter of 2017, I had six colds in six months.
‘I had my Vitamin D levels checked and I was deficient. Since then I have been taking 25 micrograms daily [more than twice the Government recommended dose] between October and April, and I have not had a cold in three years.
‘I believe that Vitamin D is an important hormone for optimising immune system function.’
One medical academic who agrees is former nurse and prominent YouTube personality Dr John Campbell.
In one video the self-proclaimed health campaigner accused the Government of inaction for failing to provide Vitamin D to every Briton in the first wave of the pandemic.
We still don’t have enough high quality data to prove the benefits
And in November he advised Britons to take at least 100 micrograms every day – ten times the Government-recommended amount.
‘The amount the NHS recommends is probably based on research that is outdated,’ he told The Mail on Sunday.
‘More recent evidence suggests that Vitamin D levels in the blood need to be double the Government’s target to see benefits for the immune system.’
Dr Campbell explained that the immune system’s fighter cells have receptors for Vitamin D – proteins that produce a reaction when they come into contact with the nutrient.
He said: ‘Studies show this reaction helps to stimulate the immune response. But if Vitamin D is low, the cells won’t function well and immunity will be compromised.’
He claimed research suggested low Vitamin D can cause the immune system to malfunction and attack healthy tissue, adding: ‘This is what we saw with severe Covid.
‘Most people who died from it did so because of an over-reaction of the immune system in response to the virus. And studies have found patients this happened to had low Vitamin D.’
However, some other large-scale studies have found the opposite.
Last October, a study of more than 500,000 hospitalised Covid patients in China found no link between Vitamin D deficiency and severe illness or death, and that taking supplements did not improve outcomes.
‘The benefits span beyond Covid,’ added Dr Campbell. ‘There are correlations between lower Vitamin D and multiple sclerosis (MS), colorectal cancer and breast cancer.’
Speaking to The Mail on Sunday’s Medical Minefield podcast, Prof Spector admitted the one illness where there might be some benefit from Vitamin D supplementation is multiple sclerosis, a condition affecting the brain and spinal cord that can cause serious disability.
Dr Campbell added, though, that there is little evidence that Vitamin D supplements offer the equivalent boost of basking in the sunshine.
‘There are plenty of anecdotal reports from patients about feeling better after taking Vitamin D, or seeing their symptoms improve,’ he said. ‘But unfortunately we still don’t have enough high-quality data to prove the benefits of supplements.
‘I think that’s because there’s no incentive for pharmaceutical companies to do research, because there’s little money to be made in Vitamin D. A positive discovery is hardly going to make drug firms millions when anyone can get it from the supermarket for a few quid.’