DR MICHAEL MOSLEY: Can eating too much be a sign your body lacks nutrients?


For most people, the past 12 months have been really tough, but some businesses have thrived — it seems 2020 was a fantastic year for supplement manufacturers, with nearly £500 million in UK sales, up a record 14 per cent compared with 2019.

We swallowed their products in record numbers partly because we’re all more health conscious, but also in the hope of protecting ourselves and our loved ones from Covid-19. 

But to what extent was this money down the drain? Which of us is really lacking in vitamins or minerals?

Let’s start with vitamin D, which I have been taking in pill form over the winter months. 

The Curtin University team suggests that as well as vitamin and mineral deficiency being more common in people who are overweight or obese, this lack of nutrients may in turn be contributing to over-eating, causing a vicious circle where your brain, knowing it is short on crucial nutrients, will make you eat more unconsciously, to make up the shortfall

The Curtin University team suggests that as well as vitamin and mineral deficiency being more common in people who are overweight or obese, this lack of nutrients may in turn be contributing to over-eating, causing a vicious circle where your brain, knowing it is short on crucial nutrients, will make you eat more unconsciously, to make up the shortfall

Vitamin D is good for your bones, but it is also vital for a properly functioning immune system and there is decent evidence it can protect you from the impact of respiratory infections, including Covid-19.

Most of our vitamin D is generated by the effect of the sun on the skin, but around one in five Britons doesn’t get enough, particularly between September and March when the sun in the UK is too weak.

But some people are much more badly affected than others. A recent report found high rates among some ethnic minorities.

The study, carried out by the University of South Australia and which looked at more than 440,000 Britons, found that 57 per cent of people from an Asian background were severely deficient in vitamin D during winter and spring and half were still deficient in summer and autumn.

The next most badly affected group were black participants (39 per cent of whom were deficient in vitamin D in winter and 31 per cent in summer). 

The NHS recommends these groups take a supplement all year round. Another large group of people who tend to have low vitamin D levels, and lack other essential micronutrients, are those who are overweight or obese.

Vitamin D is good for your bones, but it is also vital for a properly functioning immune system and there is decent evidence it can protect you from the impact of respiratory infections, including Covid-19

Vitamin D is good for your bones, but it is also vital for a properly functioning immune system and there is decent evidence it can protect you from the impact of respiratory infections, including Covid-19

This is partly because people who are significantly overweight tend to eat less nutritious food, but also because carrying excess weight, particularly around the tummy, leads to chronic inflammation — and if you have an inflamed gut, this can reduce the amount of nutrients you absorb.

There is also research which shows that if you have a lot of body fat, then this can ‘steal’ vitamin D from your blood, reducing the amount available for the rest of the body. Vitamin D deficiency is far more common in obese people than those of a healthy weight (although taking a supplement redresses this).

While making a series for Channel 4, which involved helping overweight volunteers shed some of their Covid kilos with my Fast 800 diet, I was shocked to discover how many of those we tested were deficient in vitamins and minerals.

Surprisingly few studies have looked at the vitamin status of people with a high body mass index (BMI), but those that did have disturbing findings.

In research published last year by Curtin University in Perth, Western Australia, 127 people, all of whom were overweight or obese, kept a detailed record of what they ate and drank.

The researchers also did blood tests to measure levels of vitamins A, B12, C, D, E and folic acid, as well some minerals, including iron, iodine, calcium, potassium, magnesium and zinc.

Although their food diaries suggested the volunteers were getting enough of many of these essential nutrients, their blood tests told a different story. It turned out that most of the participants were severely deficient in vitamin A, vitamin D, calcium, potassium, magnesium and zinc.

Which suggests that, whatever their food diaries said, they weren’t eating enough of the right foods, or their excess weight was significantly interfering with their ability to absorb and utilise the micronutrients they were consuming.

One of the shocking findings was despite the fact that Western Australia is hot and sunny for much of the year, 89 per cent of participants were severely deficient in vitamin D.

Perhaps that’s because fear of skin cancer means Aussies are particularly conscious about the need to keep out of the sun. 

But even worse, only 8 per cent of the volunteers had healthy levels of calcium and almost all of them were deficient in vitamin A, magnesium, potassium and zinc. The only vitamin they had a super-abundance of was vitamin C, which many took as a supplement.

One of the shocking findings was despite the fact that Western Australia is hot and sunny for much of the year, 89 per cent of participants were severely deficient in vitamin D

One of the shocking findings was despite the fact that Western Australia is hot and sunny for much of the year, 89 per cent of participants were severely deficient in vitamin D

All this matters because vitamin A boosts the immune system and keeps eyes and skin healthy, while potassium plays a vital role in preventing hypertension (high blood pressure) and helps our heart muscles work properly.

Zinc is needed for wound healing and helps fight viral infections, while magnesium is important for not only a healthy body and brain, but also helps regulate your weight. Low levels are linked to depression and poor sleep, and it has powerful anti-inflammatory effects.

And not only is calcium needed for healthy teeth and bones, but it may also help with weight loss. That’s because calcium binds to fat in your diet, ensuring less of it is absorbed.

The Curtin University team suggests that as well as vitamin and mineral deficiency being more common in people who are overweight or obese, this lack of nutrients may in turn be contributing to over-eating, causing a vicious circle where your brain, knowing it is short on crucial nutrients, will make you eat more unconsciously, to make up the shortfall.

Unfortunately, getting your vitamin and mineral levels measured isn’t straightforward.

You can get specific tests done on the NHS if you have obvious symptoms of deficiency, such as being anaemic, but if you want to get an overall picture you’d need to get it done privately.

I would anyway recommend you try to embrace a Mediterranean-style diet, rich in oily fish, nuts, seeds, legumes, vegetables, fruit and some dairy, as this will give you most of the vitamins and minerals you need.

And now that it is spring, embrace the sun. To boost your vitamin D levels you should go outside (for around 15 minutes) with your forearms, hands or lower legs uncovered and without sunscreen, ideally between 11am and 3pm.

But as the NHS warns: ‘Be careful not to burn in the sun, so take care to cover up or protect your skin with sunscreen before your skin starts to turn red.’

One of the reasons for our success as a species is not just our big brains, but we’re great at sweating.

We have ten times more sweat glands per inch than chimpanzees and it was this mutation, which assists cooling, that made it possible for our ancestors to begin world domination by coming out of the forests to hunt on the hot African savannah.

The downside is body odour (or BO). And now a real solution could come from eliminating the main villains, which include the armpit bacterium Staphylococcus hominis.

In March, a Belgian scientist, Dr Chris Callewaert, known as ‘Dr Armpit’, revealed promising results for a probiotic spray containing good microbes that displaces bad ones such as Staphylococcus hominis. So is it goodbye to BO for ever?

After Covid jab triumph, it’s time to tackle mosquitos! 

Springtime means BBQs, long evenings outdoors and mozzies.

Globally, mosquitos are not just irritating, but are our deadliest predator. The diseases they transmit, including malaria, yellow fever and dengue fever, are the leading killers in human history.

However, last week came the news that a vaccine, developed by the Oxford team responsible for the AstraZeneca Covid jab, has been shown in a small study to be 77 per cent effective in preventing malaria.

This is potentially a huge breakthrough and the world awaits the results of a bigger trial with interest.

Fortunately, we no longer have malaria in this country (the last outbreak was in 1917), but we do have lots of annoying insects. To protect yourself, avoid letting water stand in plant pots or wheelbarrows, as it’s a potential mosquito breeding ground.

Growing strong smelling herbs such as lavender, basil and peppermint is said to keep them at bay, but I haven’t seen any studies confirming this.

Nothing really beats a mosquito repellent that contains DEET, though covering up by wearing socks, trousers and long sleeves is effective. A while ago, I did an experiment with another brave volunteer in which the two of us went into a room full of ravenous mosquitos wearing nothing but shorts and a T-shirt. Afterwards, we counted our bites and found they were mainly around the feet and ankles — probably because mosquitos like the smell.

We also noticed the insects much preferred biting me. So another tip is to hang around with friends who are more attractive to mosquitos. Ruthless, but effective.

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