Weight-loss myths busted by scientists

Slimming guides in magazines, health-based television programs, and even the government, are all guilty of perpetuating myths about the best ways to shed weight. Understandably, many people are confused by (often contradictory) advice, and have difficulty separating scientific fact from fanciful fiction.

University of Copenhagen researcher Arne Astrup, along with an international team of his colleagues, has gathered popular misconceptions about weight-loss, and proceeded to debunk them.

»Outdated, observational studies infer that skipping breakfast can cause obesity, without taking into account underlying factors. We should really be paying attention to randomised double-blind studies to infer a cause-and-effect relationship«, says Arne Astrup to the University Post.

‘Wisdom’ is wrong

Many myths originate from a failure to understand the complexities of people’s energy balance, writes Astrup and his collaborators in the article. A commonly held belief is that a cumulative deficit of 3500 calories will result in a weight loss of 1 lb (0.45 kg). This rule only holds water, if applied over the span of a few days. Removing all the sugar from your coffee for a year will unfortunately not result in any weight change – the change needs to be more drastic and done over a smaller period of time.

Other myths, are based on a misunderstanding of human psychology. Skipping breakfast, common wisdom dictates, results in overindulgence later in the day. Similarly, setting too ambitious of a goal, will discourage people when they fail to meet it and quit.

Both bits of ‘wisdom’ sound completely reasonable, and yet they are wrong: Observing dieters who do, and do not, have breakfast, shows there is no difference between them. When it comes to lofty ambitions, it turns out the loftier, the better. As far as sex is concerned, the energy expenditure is roughly 3.5 calories a minute (compared to 1.5 kcal per minute for sitting on a couch).

Against misinformation

Any message that has been repeated often enough will embed itself as truth in the public consciousness, say the researchers.

»The Danish ministry of health promotes gradual weight loss, while the World Health Organisation suggests there is robust evidence that breast-feeding prevents obesity. Neither of those statements is based on fact« says Arne Astrup, adding:

»If someone can lose, say, five kilograms in the span of a few weeks, there is nothing unhealthy about that. Telling people to avoid doing so is counterproductive. The health ministry shouldn’t be publishing misinformation«

universitypost@adm.ku.dk

Stay in the know about news and events happening in Copenhagen by signing up for the University Post’s weekly newsletter here.