Ever heard the rumor that having sex burns calories? Breakfast is the most important meal of the day, snacking is bad, or gym class helps kids control weight? These are just a few of several widespread myths about obesity.
Seven popular obesity myths have been addressed in a new article published in the New England Journal of Medicine.
The authors suggest that these inaccurate beliefs are encouraging poor policy decisions, unused resources, and careless public health recommendations.
A group of researchers led by David Allison, Ph.D., associate dean for science in the School of Public Health at the University of Alabama at Birmingham (UAB), examined many articles in the popular and scientific press to separate fact from fiction. The authors referred to myths as beliefs about obesity, many of which are passionately trusted in despite little evidence.
“False and scientifically unsupported beliefs about obesity are pervasive. As health professionals, we should hold ourselves to high standards so that public health statements are based on rigorous science. In instances where the science doesn’t exist, we should conduct rigorous studies to find the answers.”
For instance, research from late last year suggests that skipping breakfast increases our desire for high calorie foods later in the day, due to brain circuits that are more prone to seeking them out while we are fasting.
Myth 1: Small, continued changes in our caloric intake or how many we burn will accumulate to create a larger weight change over the long term.
- Fact: Little changes in caloric intake or burning do not build-up indefinitely. Body mass changes eventually cancel out any change in calorie burning or intake.
Myth 2: Realistic goal-setting in obesity treatment is essential. If no goals are met, patients can become frustrated and lose less weight.
- Fact: Some data points out that people achieve more by setting more challenging goals.
Myth 3: Slowing losing weight is better than shedding the pounds quickly. Quick weight losses are likely to be gained back.
- Fact: People who lose weight quickly are actually more likely to weigh less after many years.
Myth 4: You will only lose weight when you are “ready” to do so. Health-care professionals should measure each patient’s diet readiness.
- Fact: Among people who seek weight loss treatment, research suggests that examining readiness does not predict weight loss or helps to make it happen.
Myth 5: Childhood gym classes in their current state, play an important role in the prevention of childhood obesity.
- Fact: Physical education classes currently, do not appear to counteract obesity.
Myth 6: Breastfeeding helps prevent future obesity for the breastfed baby.
- Fact: Although breastfeeding has advantages for both mother and child, data does not confirm that it protects against obesity.
Myth 7: One act of sex can burn up to 300 Kcals per person.
- Fact: In reality, it is just about one-twentieth of that on average, and not much more than resting on the couch.
The authors also addressed six other “presumptions” – defined as beliefs that are assumed to be true even though more studies are required before accurate conclusions can be drawn.
For example, some research that has been presented as fact says that eating breakfast everyday versus skipping breakfast, helps in weight loss, but few studies have been completed yielding these results.
The same goes for the common idea that consuming vegetables by themselves results in weight loss, or that snacking between meals makes you gain weight. According to the authors, not enough compelling evidence backs up these hypotheses, while some data suggest they could be false.
The investigators also pinpointed nine research-proven weight-loss facts. For instance, weight-loss programs for kids that involve parents and the child’s home, tend to reach better outcomes than programs that take place just in school or other settings.
Additionally, research has historically shown that genetic factors play a big role in obesity, but “heritability is not destiny.” Lifestyle and environmental changes can trigger just as much weight loss as treatment with weight-loss medications.
Eating a great deal of fewer calories effectively lowers weight, although it is hard for many to keep this up over the long term. Exercise is important, but only when it is often enough and powerful enough to use up more energy than taken in.
Allison and colleagues wondered why the widespread acceptance of obesity myths and presumptions is so common. The authors pointed out several factors that seem to play a part in this phenomenon.
- One is what experts refer to as the “mere exposure effect” – repeating an idea frequently enough that people start to believe it is true.
- Another factor is that people find some ideas so desirable that they do not want to let them go, despite evidence against them.
- And the other is “confirmation bias” – when one seeks out information only to confirm an opinion that is already held.
“Fortunately, the scientific method and logical thinking are there to detect erroneous statements, counter bias and increase knowledge. We believe scientists need to seek answers to questions using the strongest experimental designs. As a scientific community, we need to be honest with the public about what we know and don’t know as we evaluate proposed strategies for weight loss or obesity prevention.”
Written by Kelly Fitzgerald