Sugar – given to children by adults, lacing our breakfast cereals and a major part of our fizzy drinks – is the real villain in the obesity epidemic, and not fat as people used to think, according to a leading US doctor who is taking on governments and the food industry.
Dr Robert Lustig, who was this month in London and Oxford for a series of talks about his research, likens sugar to controlled drugs. Cocaine and heroin are deadly because they are addictive and toxic – and so is sugar, he says. “We need to wean ourselves off. We need to de-sweeten our lives. We need to make sugar a treat, not a diet staple,” he said.
“The food industry has made it into a diet staple because they know when they do, you buy more. This is their hook. If some unscrupulous cereal manufacturer went out and laced your breakfast cereal with morphine to get you to buy more, what would you think of that? They do it with sugar instead.”
Lustig’s book, Fat Chance: The Bitter Truth About Sugar has made waves in America and has now been published in the UK by 4th Estate. As a pediatrician who specialises in treating overweight children in San Francisco, he has spent 16 years studying the effects of sugar on the central nervous system, metabolism and disease. His conclusion is that the rivers of Coca-Cola and Pepsi consumed by young people today have as much to do with obesity as the mountains of burgers.
That does not mean burgers are OK. “The play I’m making is not sugar per se, the play I’m making is insulin,” he says. Foodstuffs that raise insulin levels in the body too high are the problem. He blames insulin for 75% to 80% of all obesity. Insulin is the hormone, he says, which causes energy to be stored in fat cells. Sugar energy is the most egregious of those, but there are three other categories: trans fats (which are on the way out), alcohol (which children do not drink) and dietary amino acids.
These amino acids are found in corn-fed American beef. “In grass-fed beef, like in Argentina, there are no problems,” he said. “And that’s why the Argentinians are doing fine. The Argentinians have a meat-based diet … I love their meat. It is red, it’s not marbled, it’s a little tougher to cut but it’s very tasty. And it’s grass-fed. That’s what cows are supposed to eat – grass.
“We [in the US] feed them corn and the reason is twofold – one, we don’t have enough land and, two, when you feed them corn they fatten up. It usually takes 18 months to get a cow from birth to slaughter. Today it takes six weeks and you get all that marbling in the meat. That’s muscle insulin resistance. That animal has the same disease we do, it’s just that we slaughter them before they get sick.”
But his bigger message is that cheap sugar is endangering lives. It has been added to your diet, “kids have access” to it, and it is there in all sorts of foods that don’t need it, he says. When high-fat foods were blamed for making us overweight, manufacturers tumbled over each other to produce low-fat products. But to make them palatable, they added sugar, causing much greater problems.
Cutting calories is not the answer because “a calorie is not a calorie”. The effect of a calorie in sugar is different from the effect of a calorie in lean grass-fed beef. And added sugar is often disguised in food labelling under carbohydrates and myriad different names, from glucose to diastatic malt and dextrose. Fructose – contained in many different types of sugar – is the biggest problem, and high-fructose corn syrup, used extensively by food manufacturers in the US, is the main source of it.