When It Comes to Weight Loss, Myths Abound
Is it true that walking just 20 minutes a day can lead to weight loss long-term? Are you at greater risk of regaining weight if you lose a large amount quickly? If you skip breakfast, will it make you fat? And what about those physical education classes at your child’s school? Do they really help kids lose weight?
Researchers at the University of Alabama and other institutions looked at those common questions by evaluating 40 studies on weight loss. They found seven “myths,” which they explain as “[holding] true despite substantial evidence refuting them.” One example of a myth is that breastfeeding helps prevent obesity in children.
They also looked at six “presumptions,” which they describe as “unproved yet commonly espoused propositions,” such as that eating more fruits and vegetables will help you lose weight, regardless of what else you eat.
The researchers say simply that many of the weight-loss practices they investigated aren’t based on good science, yet they have become part of popular culture and the medical community. In fact, beliefs commonly accepted, such as it is better to lose weight slowly, and only small amounts of exercise will make you lose weight, aren’t true. In fact, losing weight quickly may actually work better, because quicker results boost motivation.
Here are what they found to be “myths:”
Myth #1: If you make “small sustained changes” in physical activity (such as a 20-minute daily walk) you will lose a lot of weight over time.
Truth: The most you would lose would be 5 kilograms (about 11 pounds) over 5 years, and that’s if you didn’t increase your food intake.
Myth #2: Setting “realistic” or conservative goals for weight loss lead to more success.
Truth: It is the more “ambitious” programs that lead to better weight loss because there is more progress — and thus less frustration with reaching a goal.
Myth #3: Large, rapid weight loss is associated with poorer long-term weight success.
Truth: More restrictive diets tend to help you lose more weight and keep it off.
Myth #4: It is important to assess “diet readiness” to determine if someone is truly motivated to lose weight.
Truth: Studies show that people who say they are ready to lose weight don’t always lose a lot; neither do they keep it off long-term.
Myth #5: School physical-education classes play an important role in preventing or reducing childhood obesity.
Truth: School phys ed does not seem to have long-lasting effects on physical activity in children.
Myth #6: Breast-feeding helps prevent obesity in children.
Truth: Although breastfeeding does have positive health effects on babies and children, studies indicate it does not keep children from becoming obese.
Myth #7: Sex can help you lose weight because it burns a lot of calories.
Truth: The average male expends about 210 calories an hour during sexual activity, which is the same as walking at a moderate pace. Since the average male also spends about 6 minutes having sex, he would be expected to expend only about 21 calories.
The “presumptions” researchers looked at in the study are:
• Eating more fruits and vegetables and not otherwise changing your diet helps you lose weight.
Truth: Just adding fruits and vegetables to your diet will not help you lose weight. You must make them part of your overall food plan, and exercise as well.
• Eating regularly (not skipping breakfast) helps keep your weight down.
Truth: Eating breakfast or any other meal has no effect on losing weight.
• If you don’t learn good nutrition and exercise habits as a young child, you will not be able to do so as an adult.
Truth: This theory assumes that how you eat and exercise is developed during childhood and remains with you into adulthood. This is not always the case. Additionally, your body mass index (BMI, or measure of obesity) is more based on genes than early learning. How to calculate your Body Mass Index.
• You are at greater risk of dying if you “yo-yo” diet, or lose and regain weight over and over.
Truth: Studies conflict about these findings, but animal studies show that this is not true. Also, dieters in general are more likely to have inherent health problems that can lead to death.
• Snacking causes weight gain.
Truth: There is no “consistent” evidence that this is true. If snacks are healthy and part of a food plan, they do not make you gain weight.
• Your physical environment may contribute to your weight problem in certain situations, such as having a sedentary job, or having no sidewalks for walking in your neighborhood.
Truth: No studies support this contention.
When it comes to weight loss, there simply are no magic bullets.
But the researchers did offer these “facts” on weight loss:
- Diets do work, but they aren’t a guarantee that weight loss will be long-term.
- School programs in and of themselves will not prevent or treat obesity in children; parents must be involved at home.
- More highly structured diets, such as meal-replacement programs, lead to better weight loss.
- Weight-loss medications may be helpful, but they are not meant to be taken forever. Once medications are stopped, you may gain weight.
- Bariatric surgery is a viable option for the severely obese, and may be “lifesaving.”
- Exercise is important, no matter what, because it helps “mitigate the health-damaging effects of obesity,” the authors report.