The Independent
LONDON: There are many mixed messages coming from all angles telling people to cut out fat, sugar and carbohydrates, or engage in counter-intuitive behaviour such as intermittent fasting (or 5:2) or eating six meals per day.
Every fad carries with it the promise that it will help people lose weight, but studies show that even though three-quarters of people are on a diet almost all of the time, the British population is three times fatter than it was in 1980.
Tim Spector, professor of genetic epidemiology at King’s College London and author of The Diet Myth: the real science behind what we eat, argues that the lack of success in losing weight is due to our ignoring one key factor: the microbes in the gut.
Speaking at a London event, Spector said that there are around 2kg of microbes in the average gut, and that the microbes in the body outnumber our own cells by 10 to one.
What should really be on the menu for someone who wants to lose weight?
Spector recommends chocolate, wine, coffee and cheese.
He says every individual has a different set of microbes in their gut, which can influence processes in our bodies, including how much we weigh.
Fad diets, most of which involve either pedantic calorie control or the complete elimination of one or more food groups, have failed to help British people shed weight.
Calorie control on its own is unlikely to work, says Spector, because studies show that calories from one type of food will have a completely different effect on weight than calories from another.
In The Diet Myth, Spector says: “Our narrow, blinkered view of nutrition and weight as a simple energy-in and energy-out phenomenon and our failure to account for our microbes have been the main reasons for the miserable failure of diets and nutritional advice.”
Other diets involve the practice of “cutting out” a food group, whether it be carbohydrates, fats or everything other than cabbage soup. Spector claims that these sorts of diets could actually contribute to weight gain or ill-health, because lack of dietary diversity decreases the diversity of microbes in the gut.
“The increasing promotion and use of restrictive diets that depend on just a few ingredients,” he says, “will inevitably lead to further reduction in microbe diversity and eventually to ill-health.”
In order to stay healthy and slim, Spector says the best thing you can do is eat food that promotes the reproduction and growth of good bacteria in the gut.
According to a study of 2 000 UK twins he conducted, Spector and his colleagues found that twins with the highest levels of blood flavonoids had “lower weights, better arteries, lower blood pressure, stronger bones and a lower risk of diabetes”.
The good news is that chocolate, wine and coffee are definitely on the menu for a person looking to increase the diversity in their gut. All three of these contain polyphenols: antioxidants which feed the microbes in the gut and allow them to reproduce.
Wine and chocolate contain a type of polyphenols called flavonoids, which Spector claims have “anti-inflammatory, antioxidant and important microbial effects”.
Flavonoids can also be found in olives and nuts, but “gram for gram, cocoa has the highest concentration of poly-phenols and flavonoids of any food”.
It’s worth remembering, though, that it’s the cocoa in chocolate that has been shown to be good for your gut, not the milk and sugar that commercial chocolate is filled with. The reason why diets heavy in “junk” tend to lead to weight gain is not necessarily because of fat and sugar content, but because heavily processed food has very few ingredients.
Cheese is also a good choice, unpasteurised cheeses.
Cheeses contain “a wide variety of microbes, including bacteria, yeasts and fungi, and hundreds of species plus thousands of known and unknown strains”.
All of these things help contribute to diversity of microbes in the gut, which he claims could make you lose weight and live longer, as well as reducing the risk of disease.
Unfortunately, having a glass of wine, a chunk of camembert and an entire family-sized bar of chocolate for dinner every night is not the way to go.
Eating a wide range of foods and keeping up a varied diet, including one rich in polyphenols and healthy bacteria, is the answer, he says.