February 6, 2012
By Rob Lyons
On Thursday, high-profile science journal Nature published a commentary by three academics, which argued that sugar is a toxin and that it should be subject to similar kinds of public-health interventions as alcohol. In other words, sugar should be taxed and restricted just like booze.
One of the authors, Robert Lustig, runs an obesity clinic at a children’s hospital, part of the University of California, San Francisco. His colleagues and fellow authors, Laura Schmidt and Claire Brindis, are researchers in healthy policy. Lustig has gained an online following since 2009 for a lecture entitled ‘Sugar: the Bitter Truth’. While Lustig’s tone is rather melodramatic, there does appear to be a growing body of evidence linking refined carbohydrates and a group of related symptoms – obesity, fatty liver disease, type-2 diabetes and cardiovascular disease – that come together under the broad umbrella of ‘metabolic syndrome’.
It’s certainly the case that these chronic diseases have increased in importance in recent decades (in part because of the decline of infectious disease). Consumption of refined carbohydrates – particularly sugar – has increased, too. America has a particularly sweet tooth; the average American consumes 131 pounds (about 59 kg) of sugar and high-fructose corn syrup (HFCS) per year, up from 113 pounds per person in 1966. A teaspoon of sugar weighs about 4g, so this amounts to 40 teaspoons per person per day. (And remember, that’s an average – some people are consuming considerably more.)
The UK has a pretty sweet tooth, too. A survey for the Food Standards Agency in Scotland in 2008 found that 17 per cent of children’s calorie intake was coming from ‘non-milk extrinsic sugars’ – that is, table sugar and sugar added to food. That adds up to about 20 teaspoons per child per day.
So, we have rising rates of diseases related to metabolic syndrome alongside increased sugar consumption. Sucrose (the kind used as table sugar) and HFCS are regarded as particularly problematic by many researchers because they are both mad up of two simpler sugars, glucose and fructose. Glucose induces the production of insulin and would seem, therefore, to be a reasonable suspect in problems of insulin resistance and diabetes, with knock-on effects to do with obesity. Fructose, though it sounds healthy because it is also found in fruit, is practically Public Enemy No.1 for some health researchers due to its effects on the liver and in relation to heart disease. Thus, some see the consumption of sucrose and HFCS as a dietary double-whammy that significantly increases the risk of a number of chronic diseases.