The beginning of the year is the time when most people who need to shed some pounds turn to informercials and the Internet in search of their waistlines. But it’s hard to tell what’s what when it comes to weight loss. New research in the New England Journal of Medicine separates fad diet tips from scientifically backed ways to lose weight. And there are a lot of weight loss beliefs that science doesn’t support but that seem to work.
After doing an exhaustive Internet search themselves a group of health researchers say, “The promulgation of unsupported beliefs may yield poorly informed policy decisions, inaccurate clinical and public health recommendations, and an unproductive allocation of research resources and may divert attention away from useful, evidence-based information.”
They conducted a thorough examination of popular media and scientific literature where they identified, reviewed, and classified obesity-related myths and presumptions. They also looked at facts that are well supported by evidence, with an emphasis on those that have practical implications for public health, policy, or clinical recommendations.
Biostatistician David Allison from the University of Alabama at Birmingham led the study and says everyone is trying to do something about obesity but there is so much health misinformation out there, even erroneous and illogical beliefs endorsed by government and experts in the field.
He says, “If they are sending messages to the public that are based on erroneous understanding, arguably they may be wasting time and money and not pursuing the right things.”
Here’s what they found.
Small, sustained increases in energy intake or expenditure yield big weight change
False. The research team calls this wrong and illogical. Walking a mile every day won’t lead to a 50-pound weightloss over 5 years. If all things (calorie intake, exercise, etc.) stay the same a person might lose 10 pounds over that time frame.
Setting realistic goals for weight loss gets better results
What many people call “realistic” may be too modest and result in less weight loss. Allison and company suggest setting bigger goals for bigger weight loss.
Rapid weight loss
There is no scientific basis for telling people to lose weight slowly over time. Rapid weight loss can be a shock to your body’s system but that may not be a bad thing. Check with your doctor before any radical change in diet or exercise though. Some research has shown that some people can lose a lot of weight quickly and keep it off. Slow and steady doesn’t win every race, they say.
Even people who say they are ready to lose weight may not really be ready. The researchers note that studies show people who sign up for weight-loss programs may say they are ready but often actually lose little weight. Many doctors believe a patient has to demonstrate real commitment before they can achieve weight loss success. And they also believe that patients who feel ready to lose weight are more likely to make the required lifestyle changes. There is no evidence supporting that notion.
Physical Education classes
Just going to PE class doesn’t make kids less likely to become obese. Movement and physical exercise are very important for kids (and adults alike) but there’s no proof that PE class alone will help kids lose weight.
For over 100 years there has been a persistent belief that breast-fed children will grow up to be less obese. There is no research to back that up. The researchers say, “breastfeeding has many benefits for mother and child, but the data do not show that it protects against obesity.”
Sex doesn’t burn 300 calories. In fact the energy expended during sexual activity is not much different than sitting on the couch. With most sessions lasting an average of six minutes, doctors found that most people burn about 21 calories. That’s just 14 calories more than watching TV and certainly won’t do much to enhance weight loss. Still there are myths online that claim massive weight loss by having a lot of sex. Dr. Allison questions how this experiment was conducted.
Eating breakfast daily
Dr. Allison says that this presumption is a “very prevalent belief.” And it’s one that annoys him. Research has only been able to find an association (not a direct link) between people who skip breakfast and obesity. Some research (including a new study from Spain on Tuesday) does show that eating earlier in the day tends to boost metabolism thus making it easier to burn fat by turning food into fuel.
Early childhood eating and exercise habits
Weight-for-height indexes, eating behaviors, and early childhood food preferences don’t necessarily correlate with what happens later in life. Sometimes they do. Sometimes they don’t. Good habits can be formed later in life. Who liked brussel sprouts as a kid?
Eating fruits and vegetables
People who eat more fruit and vegetables eat less other kinds of food. And fruits and veggies are generally better for you and have fewer calories than hamburgers and potato chips. So the resulting reduction in calories is greater than the increase in calories from the fruit and vegetables and can help maintain weight or promote weight loss.
No-no on the yo-yo dieting
While yo-yo dieting can be hard on the body, it isn’t fatal. Weight cycling may be associated with higher mortality only because mortality rates have been lower among persons with stable weight than among those whose weight fluctuates over time.
Snacking makes you fat
Eating snack foods are not bad by themselves. But most people don’t have extra protein or vegetables at subsequent meals to make up for the snack. That can lead to weight gain. Observational studies have not shown a consistent association between snacking and obesity or an increased body mass index. The researchers say that randomized, controlled trials also do not support this presumption.
The built (i.e., human-made) environment
The idea that sidewalk access or proximity to a park will affect obesity is unclear. Given easy access to these neighborhood features, people are more likely to walk or exercise which will give them a better shot at avoiding obesity. But it’s not the neighborhood features that do the activity it’s the people in the neighborhood.
Heritability is not destiny
Dr. Allison et al. says, “Although genetic factors play a large role calculations show that moderate environmental changes can promote as much weight loss as the most pharmaceutical agents available.” The trick of course is identifying key environmental factors and successfully influencing them. Research has shown that when that happens obese people can lose a clinically significant amount of weight.
Diets (eating less)
This is a very effectively weight loss tool but trying to go on a diet or recommending that someone go on a diet generally does not work well in the long-term. Dieting is difficult.
Exercise increases health
An increased level of exercise promotes health and prevents the health-damaging effects of obesity, even without weight loss.
Physical activity or exercise
For physical activity to affect weight, there must be a substantial quantity of movement, not just participation. Merely showing up doesn’t guarantee results. Although it is the first step.
Long term weight loss maintenance leads to lower weight.
Obesity is best conceptualized as a chronic condition, requiring ongoing management to maintain long-term weight loss success.
Programs for overweight children that involve the parents and the home setting promote greater weight loss. Programs only in schools or other out-of-home structured settings may be convenient or politically expedient but net fewer long term results.
Meal-replacement products promote greater weight loss.
More structure regarding meals is associated with more weight loss when compared to a more holistic food approach of balance, variety and moderation.
Drugs can help patients
There is no magic pill. But while science is trying to figure out how to alter the environment and individual behaviors to prevent obesity some pharmaceutical solutions achieve clinically meaningful weight loss and maintain the reduction as long as the drugs are used.
One of the more drastic weight loss solutions available but surgery shows results in long-term weight loss and significant reductions in diabetes and mortality rates. This life-changing and life-saving measure is only for severely obese people.
To reach the scientific gold standard Allison says scientists would need to randomly assign people to a group of experimental subjects or a control group, keep all other variables except the one they are studying constant and watch what happens over time. He says, “Why do we spend all this time and money arguing about obesity, passing laws, instead of doing the simple randomized trial?”
Allison says beyond conducting randomized experiments to test obesity myths, drugs and surgery tend to work because they are already using randomized, controlled clinical trials before going to market.
Not everyone agrees with that assessment. Marion Nestle of New York University called the whole study “weird.” The nutrition professor tells the Today Show, “I can’t understand the point of the paper unless it’s to say that the only things that work are drugs, bariatric surgery, and meal replacements, all of which are made by companies with financial ties to the authors.”
The 20 co-authors on the study included a long list of food, beverage and weight-loss product companies they had financial ties with, which Dr. Nestle views as a conflict of interest.
The bottom line, the researchers say, is that “false and scientifically unsupported beliefs about obesity are pervasive in both scientific literature and the popular press.”
And fat chance that is going to change anytime soon.
The 20 researchers on this study had their work supported in part by a grant (P30DK056336) from the National Institutes of Health. The views expressed in the article are those of the authors and do not necessarily represent the official views of the National Institutes of Health.
List of disclosures
Dr. Astrup reports receiving payment for board membership from the Global Dairy Platform, Kraft Foods, Knowledge Institute for Beer, McDonald’s Global Advisory Council, Arena Pharmaceuticals, Basic Research, Novo Nordisk, Pathway Genomics, Jenny Craig, and Vivus; receiving lecture fees from the Global Dairy Platform, Novo Nordisk, Danish Brewers Association, GlaxoSmithKline, Danish Dairy Association, International Dairy Foundation, European Dairy Foundation, and AstraZeneca; owning stock in Mobile Fitness; holding patents regarding the use of flaxseed mucilage or its active component for suppression of hunger and reduction of prospective consumption (patents EP1744772, WO2009033483-A1, EP2190303-A1, US2010261661-A1, and priority applications DK001319, DK001320, S971798P, and US971827P); holding patents regarding the use of an alginate for the preparation of an aqueous dietary product for the treatment or prevention of overweight and obesity (patent WO2011063809-A1 and priority application DK070227); and holding a patent regarding a method for regulating energy balance for body-weight management (patent WO2007062663-A1 and priority application DK001710).
Drs. Brown and Bohan Brown report receiving grant support from the Coca-Cola Foundation through their institution.
Dr. Mehta reports receiving grant support from Kraft Foods.
Dr. Newby reports receiving grant support from General Mills Bell Institute of Health and Nutrition.
Dr. Pate reports receiving consulting fees from Kraft Foods.
Dr. Rolls reports having a licensing agreement for the Volumetrics trademark with Jenny Craig.
Dr. Thomas reports receiving consulting fees from Jenny Craig.
Dr. Allison reports serving as an unpaid board member for the International Life Sciences Institute of North America; receiving payment for board membership from Kraft Foods; receiving consulting fees from Vivus, Ulmer and Berne, Paul, Weiss, Rifkind, Wharton, Garrison, Chandler Chicco, Arena Pharmaceuticals, Pfizer, National Cattlemen’s Association, Mead Johnson Nutrition, Frontiers Foundation, Orexigen Therapeutics, and Jason Pharmaceuticals; receiving lecture fees from Porter Novelli and the Almond Board of California; receiving payment for manuscript preparation from Vivus; receiving travel reimbursement from International Life Sciences Institute of North America; receiving other support from the United Soybean Board and the Northarvest Bean Growers Association; receiving grant support through his institution from Wrigley, Kraft Foods, Coca-Cola, Vivus, Jason Pharmaceuticals, Aetna Foundation, and McNeil Nutritionals; and receiving other funding through his institution from the Coca-Cola Foundation, Coca-Cola, PepsiCo, Red Bull, World Sugar Research Organisation, Archer Daniels Midland, Mars, Eli Lilly and Company, and Merck.