Modern Diet Myth No. 1: Eating McDonald’s makes you fat and sick

For years, the food served at McDonald’s restaurants has been used as an example of all that is wrong in modern western diets – it’s simple, fast, cheap and American, and therefore couldn’t possibly be good for us. In his 2004 movie Super Size Me United States film maker Morgan Spurlock set out to demonstrate that McDonald’s food actually makes people fat and sick, using himself as a guinea pig.

The Spurlock ‘experiment’

For 30 days Spurlock ate only McDonald’s food and documented the effects on his physical and psychological well-being on film. The effects were dramatic: he gained over 11 kilos in weight; his blood cholesterol went up; fat built up in his liver; and he experienced sexual dysfunction and swings in mood. At last, here was all the proof we needed that eating McDonald’s food makes you fat and sick!

In reality it was nothing of the sort. Proof comes from scientific experiments and Super Size Me bore no resemblance to science. When conducting dietary experiments researchers are careful to control for all the factors that might affect the result. If two things change in a diet, how do you know if an adverse effect is due to one thing or the other?

Spurlock gave his audience the impression that he was testing the QUALITY of McDonald’s food. However, during his 30-day ‘experiment’ he also changed the QUANTITY of food that he ate. In fact, he absolutely stuffed himself, doubling his calorie intake. This binge was why he put on so many kilos and probably why his blood cholesterol and liver fat increased.

The fact that he was eating McDonald’s food actually had nothing to do with his weight gain. Many dietary experiments have shown that diets with widely differing composition have exactly the same effect on body weight if calories are kept constant, and physical activity remains the same. These are the things that determine whether body weight moves up or down. Spurlock actually lowered his level of physical activity during his month-long feast, presumably to ensure the results were as bad as possible.

Image: source

Spurlock’s motive

What was Spurlock’s motive? If the intention had been to inform the general public of the facts Spurlock would have teamed up with some nutrition researchers and filmed a real scientific study into the effects of McDonald’s food. I suspect he was aware that the results would hardly have been big news.

At best, Spurlock’s movie may be an extreme case of white hat bias i.e. bias leading to the distortion of information in the service of what may be perceived to be righteous ends. But the predetermined outcome and the misrepresentation of its cause surely pushes ethics to the limit.

Alternatively, maybe Super Size Me was just a stunt designed to generate a lot of publicity and to tarnish McDonald’s name. Irrespective of what we think about the nutritional quality of McDonald’s food, wouldn’t we all be better off if we just heard the facts?

Declaration: Bill Shrapnel has no association with McDonald’s.

 

Fatty liver

Fatty liver is reaching epidemic proportions in western countries. What causes it and what diet and lifestyle measures can be used to manage it?

About 30% of adult Australians are thought to have non-alcoholic fatty liver disease – fatty liver for short – and its prevalence is increasing. In its early stages fatty liver is of minor concern and there are no symptoms. But it can progress to a stage called NASH where liver cells begin to be damaged and this is associated with inflammation. At the next stage the risk of cirrhosis of the liver increases which may lead to liver failure and even cancer of the liver. Together, fatty liver and NASH are now the number one cause of liver disease in Western countries. However, the major cause of death in people with fatty liver is cardiovascular disease.

What causes fatty liver?

Fatty liver develops when the liver’s normal processes of delivery and removal of fats go awry. Although the exact cause is not known several things could be going wrong:

• Perhaps too much fat is being delivered to the liver
• The liver may have a problem ‘burning’ fats for energy
• Fat (triglyceride) production by the liver may be increased
• The movement of triglycerides from the liver into the bloodstream may be impeded.

But what is the underlying cause?

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The decline of breakfast

Fifteen percent of Australian children head off to school without having had any breakfast and the figure is rising. Among secondary school students it’s closer to 20 percent. What are the implications and what should nutritionists do?

The CensusAtSchool survey

CensusAtSchool is an annual nationwide survey of students’ everyday lives, experiences, opinions and interests conducted by the Australian Bureau of Statistics. Participation is voluntary so the data produced are not necessarily representative of the whole school population, just those who completed questionnaires. Nevertheless, the findings provide insight into the trends, habits, attitudes and lifestyles of Australian students.

According to the latest survey of nearly 24,000 children, about 15 percent do not consume breakfast and the figure has been rising in recent years. There is considerable variation in breakfast skipping across Australia, from 12 percent of Victorian school children to over 22 percent in the Northern Territory.

Earlier reports from the same survey have highlighted how breakfast consumption declines as children get older. Typically about 7-8 percent of primary school children skip breakfast but the figure rises to about 20 percent for children at secondary school.

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Gluten-free diets: who’s spreading the bulldust?

Gluten-free diets are good for people with coeliac disease but nobody else, yet going gluten-free has become a major international food trend driven along by celebrity endorsement. Hocus-pocus like this doesn’t just happen; it’s sophisticated food marketing on a global scale.

Coeliac disease

All dietitians and nutritionists are familiar with coeliac disease – the gastrointestinal disorder suffered by about one percent of the population. It’s due to an inflammatory response to gluten, a protein found in wheat, rye and barley, which damages the gut wall resulting in malabsorption of nutrients leading to gas, distension, diarrhoea and weight loss. Adopting a gluten-free diet provides great benefits to those with coeliac disease but it has long been thought that such a diet offers no benefit to people without the condition.

What about gluten sensitivity?

More recently, a hypothesis has emerged that there is a spectrum of reactions to gluten with full-blown coeliac disease at one end and mildly irritable bowel at the other. The term gluten sensitivity has been coined to describe the “no man’s land” in the middle. If it’s true, millions of people could be affected. But gluten sensitivity is almost impossible to diagnose as the gut wall is not damaged and there is no diagnostic biomarker. So, if you have tummy troubles and they seem improve when you go on a gluten free diet, well, maybe, perhaps you have gluten sensitivity.

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The demise of the Danish fat tax

As governments struggle to address the rising prevalence of obesity and other chronic diseases there have been increasing calls for taxation on selected foods as a means of improving the quality of national diets. Last year Denmark introduced the world’s first ‘fat tax’, but in an abrupt turnaround the much maligned tax has been repealed. What went wrong?

Targeted taxation of foods

The rationale for targeted taxation of foods to improve health draws on the fundamental economic principle that the demand for any good is related to its price. If the price goes up, the demand goes down, and vice versa. Hence the demand for goods is said to be ‘elastic’. Viewed through this prism, addressing diet-related chronic disease becomes straightforward – use the tax system to increase the price of junk foods and lower the price of healthier foods. Too easy.

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