© Rio Schroer . Chris Von Tuleken - Reese Schroer with epidemiologist Dr. Spector at the Hay FestivalTop gut doctor says people who take vitamin supplements are "dumb."
Tim Spector, an epidemiologist and co-founder of the Joe Diet program, which analyzes users' endurance, lipids and blood sugar levels, and author of Food for Life, who spoke at the Hay Festival with infectious disease doctor Chris van Tulken, said supplement manufacturers are the "fast food companies of the future".
"These supplements are run by the same company, they're going to be the new junk food company in the future - their budgets are huge," he says.
“These are not artisans making great organic supplements in the back of a warehouse in Somerset. Everything is made in a big factory in China and you have no control over what it is.
"It turned out that 99 percent of them don't work at all, so we paid the supplement in full," he added.
A recent US study found that taking a daily multivitamin reduced age-related memory loss in people over 60 over three years.
Improving mental performance
American researchers found that regular intake of the vitamin improves general cognitive activity, memory and concentration in adults.
However, study leader D. Adam Brickman, a professor of neuropsychology at Columbia University's Vagelos College of Physicians and Surgeons, cautions, "Not every type of supplement should replace the usual way of obtaining the same micronutrients."
"Although multivitamins are generally safe, people should always check with their doctor before taking them," he said.
© Available from Telegraph Intestinal SupplementSpector told the HI audience that eating less meat and dairy is more important to saving the planet than driving less or flying less.
"If we're concerned about climate change, one of the most important things we can do is cut back on meat and dairy, especially beef and lamb, and drink milk," he said.
"It's more important than flying to Spain or traveling a lot on vacation. Organic foods are proven to be good for your health and vice versa. You don't have to give them up completely."
drink wine
Spector previously suggested that mixing different grape varieties could improve health, as drinkers try thousands of different varieties to boost immunity and ward off disease, as well as improve mental health.
"Drinking wine is primarily for pleasure, but you think, 'Can I try a different bottle or a variation that might be better for me and that I can enjoy?' I think about it.
Diversity is also important; As with food, eating a variety of grapes in your diet will help maintain a diverse gut microbiota and improve the health and diversity of your gut.
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