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Report challenges weight-loss myths

Debbie Lee believes she understands the mindset of someone wanting to lose weight.

Having been Gainesville Health and Fitness Center’s marketing director for more than 20 years, Lee recognizes that the new clients who come in looking to improve their diet and increase their exercise regiment have made difficult decisions. However, thanks to what health-conscious weight watchers may read online and in popular magazines, they can develop some false impressions, she said.

They may think they can lose 10-25 pounds immediately and not have to work hard to keep the weight off long term, or they may be convinced the diet a friend of a friend tried of eating one meal a day or grapefruit every day or 10 apples a day may work just as well for them.

Misinformation is prevalent in weight-loss culture, and a Thursday report published in the New England Journal of Medicine disputes seven myths about obesity and questions the validity of other popular assertions about losing weight.

The report’s researchers reviewed online media and articles in popular science publications to find the unfounded assumptions and out-right fiction on weight loss circulating the Internet.

Misinformation is important to quash because it can lead to poor health policy decisions and unhealthy clinical recommendations, according to the report.

Perpetuating myths about weight loss can also lead to misdirection of precious resources and research funding, said Krista Casazza, one of the report’s authors and an assistant professor in the University of Alabama at Birmingham’s nutrition sciences department.

Instead, it’s important to encourage people to fund proven, scientifically sound strategies and not just accept long-held beliefs as fact, Casazza said.

In fact, she said she was surprised to find some long-believed concepts lacked scientific evidence.

Dieting Myths: Realistic Goals, Caloric Burns, Eating Less

Casazza, who runs 15 miles a day and is a vegetarian, said she didn't expect to find insufficient evidence for the idea that dieters who set realistic goals won’t get upset about not reaching their goal and lose less weight.

The report found no data supporting this idea, and some studies show ambitious weight-loss goals can lead to more pounds shed even if the goal isn't reached.

The report finding gaining a lot of press is refuting the idea that people can burn hundreds of calories having sex.

In reality, participants will burn about 3.5 calories a minute, the same rate as someone walking 2.5 miles an hour. The actual energy spent from of an intimate night is only 14 calories.

Even in the gym, certain activities have inflated calorie burn counts, Lee said. People will think they burn 500 calories after 15 minutes on a treadmill based on the equipment manufacturer’s information, but those numbers are impossible for anyone other than an elite runner.

Additionally, the notion that consistently eating a little less and exercising a little more than usual will lead to long-term weight change is based on an outdated weight loss equation, the report said.

The report found weight watchers’ levels of readiness before dieting didn't affect how many pounds they shed, and losing a lot of weight fast leads to more weight lost in the long term. This went against the popular idea that slowly losing weight will have better long-term results than quickly shedding pounds.

Childhood Obesity Myths: Breastfeeding, Gym Class

Myths the report found regarding children include physical education classes preventing childhood obesity and breastfeeding infants makes them less prone to obesity later in life.

Gym classes are not shown to have a definite effect on a child’s body-mass index, a weight-to-height ratio revealing obesity, according to the report. Such classes are too infrequent, too short and not intense enough.

Still, the report suggests a certain combination of a gym class’s length, quality and occurrence could help overweight children, and the researchers encouraged breastfeeding for other benefits to the mothers and infants.

Weight Loss Presumptions and Facts

The report identified six assumptions made about losing weight that aren't scientifically proven or disproven.

These assumptions include regularly eating breakfast prevents weight gain, teaching children good exercising and eating habits will influence their weight later in life, and yo-yo dieting, where a dieter gets stuck in a cycle of trying to lose regained weight, can kill.

Debbie Lee said she believes raising her two kids, now 21 and 17, in an exercise-friendly environment prepared them for being more active as adults.

The report said eating more fruits and vegetables without changing behavior will lead to the same weight or even weight gain, and no data showed relations between weight gain and snacking.

Finally, the man-made environment where people live, including the area’s architecture and the availability of sidewalks, roads and parks, wasn't proven to affect residents’ weights.

Co-author Casazza said some presumptions were left out of the report, including the uncertainty of whether daily self-weighing affects weight loss or not. She said her team wants to eventually publish another, more comprehensive report.

Proven factors that can affect weight include dieting, food choice, genetics, environment and exercise, according to the report. Drugs and surgery can help appropriate patients, and overweight children can benefit from weight loss regiments at home.

Making a Change

The abundance of wrong information available to weight watchers doesn't hinder fitness centers’ missions, Gainesville Health marketing director Lee said. Instead, it’s become part of the job.

She and the rest of her center’s communications staff regularly scour the Internet for the latest health news, accurate or not, just to be aware when a client comes in with questions.

“We expect for people to come in with lots of myths, with lots of misinformation that they've accumulated overtime,” she said. “People get so distraught about their situation, they start grabbing any and every piece of information out there that could possibly help them make the weight-loss changes that they want. So, by the time they get to us, they've got a lot of misinformation.”

Weight watchers need to find the combinations of diet and exercise that work best for them individually, Lee said. She advised investing in a calorie counting device people can wear with them to truly see how many calories are burned for certain activities.

Lee got hers for doing stadiums, but said she was surprised by how many calories she spent doing housework, laundry and washing windows.

The hardest part of changing for weight watchers is getting started, she said. It’s important to find that push.

“Do something, even if it’s not perfect do something that is movement oriented most days of the week,” she said. “Get in motion, even if it’s not anything formal or structured, until you figure it out or get someone to help you.”

Wade is a reporter for WUFT News who may be contacted by calling 352-392-6397 or emailing news