Dr Alan Barclay
Eat foods, not nutrients
In his NYT piece Unhappy Meals Michael Pollan documents the ‘shift from eating food to eating nutrients’ and argues that relying solely on information regarding individual nutrients has led people and policy makers to repeatedly make poor decisions relating to food and nutrition over the last forty years.
The ‘low fat’ story is a good example of this nutritionism at work. Research from the 1960s and 1970s linking high fat (especially saturated fat) diets with cardiovascular disease, led to widespread government health recommendations to cut back on fat intakes – a mantra quickly enshrined in dietary guidelines the world over to beat heart disease and the battle of the bulge. The food industry responded by developing a vast array of reduced and low fat alternatives (often substituting refined carbohydrates for the fat). People responded too, cutting back on full fat products and tucking into the ‘diet’ and ‘lite’ alternatives with gusto. And although heart health statistics improved, the scales told a different story. People just kept on getting fatter. Why? Well as Arne Astrup points out in Saturated fat and heart disease – the latest evidence in this issue, what you replace fat with really does matter.
The huge success of Dr Atkins’ New Diet Revolution with his message that excessive carbohydrate consumption (not fats saturated or otherwise) was the bad guy behind the US obesity epidemic shone the spotlight back on carbohydrates in general. Post Atkins Revolution, one carbohydrate in particular – fructose - has been singled out as the cause of the US obesity epidemic, especially in the form of high fructose corn syrups used in increasing amounts by the US food industry from the late 1970s. The parallel increase in rates of overweight and obesity with the increasing use of HFCS has led some researchers to believe that fructose is in fact a major cause of the obesity epidemic. Yet rates of overweight and obesity have increased around the globe, even in countries like Australia (we are right up there in the fattest nations league) where high fructose corn syrups are not generally used.
At the University of Sydney's Human Nutrition Unit, we decided to explore further the links between increased consumption of sugars (including fructose) and the global obesity epidemic. In our paper published in April in Nutrients we investigate trends in sugars consumption in Australia, UK and the US between 1980–2003 to see whether it was likely that increased consumption was the cause of the obesity epidemic in these nations.
In Australia, the UK and US, per capita consumption of refined sucrose (table sugar) decreased by 23%, 10% and 20% respectively from 1980–2003. However, when all sources of nutritive sweeteners, including HFCS, were considered, per capita consumption decreased in Australia (16%) and the UK (5%), but increased in the US (23%). During this period, the prevalence of obesity has increased three-fold in Australians and at least doubled in the UK. So while excessive consumption of fructose in the form of HFCS may be a contributing factor to the US obesity epidemic, it seems unlikely that it is a major cause elsewhere.
It appears that in Australia at least, people took the message to eat less sugar very seriously. Australians are very good at adopting public health messages with one of the lowest rates of cigarette smoking in the world due to decades of the Quit campaign, and the Slip, Slop, Slap campaign to reduce sun exposure has been so successful that rates of vitamin D deficiency are skyrocketing.
Maybe the real problem is focusing on individual nutrients in foods to find a key culprit to blame for of the obesity epidemic. And while we obsessively count the grams of fat or sugar we consume, we inadvertently consume more food and drink overall. Also, we often overlook the fact that most of us are less physically active than we were a few decades ago.
Of course, foods and traditional diets are far more than just nutrients. Food is one of life’s great pleasures to be enjoyed with family and friends. For each of us it is part of our cultural heritage and for many integral to religious beliefs. If we want to deal with the current obesity epidemic without totally destroying our enjoyment of food, life and the environment, let’s encourage people to enjoy whole foods and beneficial dietary patterns such as the Mediterranean diet (and here I mean both what was eaten and how mealtimes were enjoyed), rather than blaming specific nutrients.
For more information email Dr Alan W Barclay here: firstname.lastname@example.org
For more information about the GI Symbol Program
Dr Alan W Barclay, PhD
Chief Scientific Officer
Glycemic Index Foundation (Ltd)
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