Hi Jo,
Here’s the article. Interesting and good to discuss!
Calorie counting won’t solve the obesity crisis
Jenni Russell
Published at 12:01AM, February 18 2016
Evidence is growing that the destruction of our gut bacteria by processed food is the real enemy
Something very curious happened in Britain in the mid-1980s. Obesity rates had scarcely shifted in the 20 years since records were kept. They were more or less steady at around 7 per cent. Then, overnight — or overyear — they rocketed, going into a steep climb for the next 20 years. Obesity almost trebled and every age group was affected. Whether they were 16 or 60, people suddenly started getting fat.
Exactly the same thing happened in America, except that it took place five years earlier. The US graphs show a slow rise in adult obesity from 1950 to 1980, from around 12 per cent to 15 per cent of the population, an increase of only 1 per cent a decade. Then in 1980 the line on the graph starts shooting up rapidly, both for children and adults, so that by 2000 the adult obesity rate had more than doubled to 35 per cent.
Nothing in the pattern of physical activity in either country explains this dramatic change. Increases in car use and television watching, and declines in physical activity and housework, all show a gradual trend. There were no sudden spikes, let alone any that are parallel with the obesity figures. And the fact that all age groups were affected at the same time means that single explanations for one group aren’t sufficient.
Nor does an increase in calorific intake provide a simple explanation. In America, it’s true, the number of calories in the food chain shot up over those two decades by around a sixth. But in Britain the number of calories consumed per person actually fell markedly. From 1974 to the early-2000s our average daily calorie count dropped by a fifth.
If neither calories nor physical activity explain the surge, that implies something else must have changed: the way our bodies work. There must have been an alteration in the way we process food and use the surplus.
Last autumn a major study in North America confirmed that the popular explanation of the obesity surge — that it’s solely due to eating more and moving less — just isn’t true. Scientists at York University in Toronto examined the dietary data of thousands of Americans from 1971 to 2008, and the physical activity data of thousands more from 1988 to 2006. That showed something remarkable. In 2006, people who ate the same amount of calories as their counterparts in 1988 and did the same amount of exercise were nevertheless 10 per cent fatter. In other words, for some reason it has become much harder to stay thin, or even average, than it was 30 years ago.
The puzzled researchers have suggested several possible causes. Environmental chemicals, from the plastics used in food production to flame retardants, could be changing our hormones. The explosion in antidepressants, oral contraceptives and antibiotic use, all associated with weight gain, is another. The third suggestion is the one that increasing numbers of scientists are focusing on: the destructive transformation of our gut bacteria — our microbiome — by the rapid changes in the western diet since 1980.
There are dozens of human and animal studies demonstrating how contemporary diets rich in processed food, transfats, artificial sweeteners, additives, corn, soya and wheat devastate the huge variety of good bacteria that live in our guts, and replace them with strains that create inflammation and weight gain. That switch in our eating habits took off in the 1980s, when we ditched butter, full-fat milk, eggs, red meat and three meals a day in favour of frequent snacks, sugary drinks, ready-made meals and low-fat, high-carbohydrate food. Instead of an internal garden we created an arid landscape filled with weeds.
Gut biology has gone from being an esoteric area to a mainstream interest in the past five years, as researchers have realised just how vital it is to our health. The key understanding is that once they are established, our gut bacteria determine how our bodies respond to food. Thin people develop colonies that keep them lean; fat people the reverse.
In a fascinating 2013 experiment by the genetic epidemiologist Tim Spector, from King’s College London, researchers took intestinal microbes from pairs of twins where one sister was obese and one lean, and transferred them into mice. All mice were fed the same food. Yet the mice given the “obese” bacteria grew fat. The mice with the lean sister’s bacteria stayed lean. Then, just to prove the point, the scientists gave the fat mice bacterial transplants from the lean ones — and the fat mice lost their excess weight.
The clear implication of the research is that if we continue to eat a classic western diet then even if we reduce our calories we’ll fight to lose weight or keep it off. Our bacteria will act like a fifth column, simultaneously fattening us and sending us subversive chemical messages demanding more sugar or fat. The exciting element of the theory is that just as our microbiome was ravaged by dietary changes, so it’s probably in our power to rebuild it — and the changes can start in days.
Dr Spector and other leading figures in this field say the solution is simple; replace processed food with the natural foods we used to eat, particularly spices, herbs, fermented foods and fibre-rich plants. Variety is the key to internal regeneration. We used to eat around 150 different foods; now many of us eat only 20, packaged in 50 ways.
And if broccoli for breakfast, nuts and sauerkraut for lunch and green smoothies for snacks is too much to bear, there’s always the cheat’s option. Sidle up to the skinniest person you know and find out what it might take for them to give away their good bacteria.
11:37 am
19 Feb 16