Like most people, Kevin Hall once believed that the reason for gaining weight was simple: “Why eat a lot and move more?” In the view of Hall, a physicist, losing weight is a combination of calorie intake and calorie burn. relationship between. However, he eventually proved his views wrong through research.
Hall is a scientist at the National Institutes of Health. A few years ago, at the recommendation of a friend, he started watching the reality TV show “Super Weight Loss King.” He said, “Those people lost 20 pounds in a week.” The show fits the public perception of weight loss: exercise is extremely intense High, dietary requirements are also very strict. Losing 20 pounds in a week is truly amazing, though. To understand how these people did it, Hall decided to study 14 show contestants and write a paper about it.
On reality TV, contestants did lose a lot of weight in a short period of time. After one season of the show, the contestants lost an average of 127 pounds and lost about 64 percent of their body fat. Hall believes that if his research can reveal physiological changes in these athletes, it may help the huge overweight population.
What he didn’t expect, however, was that even with the seemingly perfect weight loss conditions on TV—a tough but well-instructed coach, a good-looking doctor, a strict diet plan, and intense training—the body would lose weight in the long run. Always trying to grow back those lost fat. Of the 14 contestants Hall studied, 13 ended up regaining 66 percent (the average) of the weight they lost on the show, and four were even fatter than they were before the show.
Even the most motivated dieter may be tempted to quit after learning this frustrating fact. “People might think, why bother?” Hall said. But in today’s society, the importance of losing weight is increasingly prominent. The medical community generally believes that excess body fat greatly increases the risk of major diseases, including type 2 diabetes, heart disease, depression, breathing problems, cancer, and reproductive disorders. A 2017 survey found that obesity causes more early preventable deaths than smoking in the United States. These factors have spawned a multi-billion-dollar weight-loss industry with products ranging from diet pills to diet plans to gym memberships.
Related research has also grown substantially. These studies help scientists understand many questions about weight loss: Why is dieting so difficult? Why is it harder to maintain long-term weight loss? Why common sense about weight loss doesn’t apply to everyone The U.S. Centers for Disease Control and Prevention said the scientists’ findings could bring new hope to the 155 million overweight Americans. For example, researchers agree that exercise, despite its health benefits, is not a reliable way to lose weight in the long term. In addition, the simple inequality of “calorie intake and calories burned” has gradually been replaced by a more complex theory: diet structure, not exercise to burn fat, maintains weight loss.
Scientists also believe that the recipes that work best for you are likely to be useless to your neighbors. The same recipes—from low-fat diets and vegans to low-carb and paleo diets—can have wildly different effects on different people. Frank Sachs, a professor of preventive medicine for cardiovascular disease at the Harvard T.H. Chan School of Public Health, said: “Some people lose 60 pounds on a diet and maintain it for two years, while others follow the same diet and gain 5 pounds. “If we can understand why, it can greatly help people who need to lose weight.”
Research by scientists such as Hall and Sachs suggests that the key to weight loss appears to be a personalized diet, rather than a fad diet. While losing weight isn’t easy, there’s growing evidence that anyone can achieve a healthy weight with the right approach.
Lena Wing, a professor of psychiatry and human behavior at Brown University, has been working with the National Weight Control Registry, tracking those who successfully lose weight and maintain it. Wen’s partner James Hill, an obesity researcher at the University of Colorado, said: “Initially, there was a general belief in society that almost no one succeeds in losing weight. We didn’t believe it, but we couldn’t falsify it because we didn’t have the data.”
The registration threshold for the National Weight Control Registry is to lose more than 30 pounds and maintain it for at least one year. Today, the center’s list includes more than 10,000 people from all 50 states who have lost an average of 66 pounds over five years. The most thought-provoking point is that everyone on the list lost a lot of weight, but in different ways: About 45% of them said they lost weight on a diet, and another 55% participated in a systematic diet. project.
The researchers found that these people had something in common: 98% of the study subjects adjusted their eating patterns, and most of them reduced their daily food intake; 94% of the study subjects increased the amount of exercise, and the most popular form of exercise was walking. “There’s nothing special about what they do,” Wen said. “Some are more exercise-focused, some follow a low-carb diet, and some just eat low-fat foods. The only thing they have in common is a sense of their day-to-day behavior. make changes.”
When asked how to maintain their weight loss, most of the study participants said they ate breakfast every day, weighed at least once a week, watched TV for no more than 10 hours a week, and exercised an average of 1 hour a day. In addition, the majority of study subjects did not consider themselves aggressive (competitive, competitive, impatient, impatient, and time-critical), suggesting that it is not only those who are obsessed with planning that stick to diets. Many successful dieters call themselves “morning people.” The researchers also found that people who can maintain their weight loss over the long term are often not driven by a slender waistline, but by a sense of health concerns or a desire to live longer and be with loved ones.
Staff at the National Weight Control Registry said the subjects were not gifted and were more likely to lose weight, after all, they had also experienced many failures to lose weight. The secret is that they have a strong drive to keep trying different weight loss methods until they find what works best for them. “It’s hard to lose weight and keep it off,” Hill said. “But at the same time, it’s definitely possible, and once you start, life gets better.”
Hill, Wen, and their colleagues agree that the most inspiring experience may be the simple fact that no two of the more than 10,000 real-life “super slimmers” lose weight exactly the same.
The Ottawa Obesity Medical Research Institute of Canada was established based on this view. In its weight loss program, all participants start with the same six-month diet and exercise plan, but they can deviate from the plan according to their needs and find the best way to lose weight under the guidance of a doctor. This weight loss program takes a “whole person” approach, meaning that everyone’s weight loss program is influenced by multiple factors including behavior, psychology, budget, and physiology. “Our plan includes getting enough calories and things like protein, but we don’t have to stick to that,” said Institute Director Yuni Friedhoff. “We try to get to the root of the problem and then make adjustments. Everyone involved. in different ways.”
The key to weight loss seems to be a personalized diet.
In most cases, people need to try a number of different plans to find the one that works best for them. Judy Kings, 52, an information technology program executive living in Ottawa, has been overweight since childhood. When she came to the Obesity Medical Institute in 2007, she weighed 240 pounds. While she had some success with Weight Watchers in her 20s, the stress of being unemployed later caused her to overeat and regain her weight. Every Monday, Kings wakes up with the determination to start a diet and never touch dessert again, but always gives up after days or even hours. “Unless you’re super fat, you don’t understand what it’s like to feel like – having a lot of pressure and people always feel like it’s your fault,” she said.
A March 2017 study found that people who internalized the shame associated with obesity had a harder time maintaining weight loss. As a result, experts believe that redirecting effort from a number on the scale to a fitness goal yields better results. “If you’re just focusing on weight, you might be giving up some beneficial changes,” Hall said.
Kings lost 75 pounds in five years at the institute. After that, she paid attention to the amount of food she ate, recorded the food she ingested, and insisted on eating less and more meals, and maintained the weight loss effect for 5 years. She credits her weight-loss success with a slow, steady rhythm. While she’s not too enthusiastic about exercise, keeping track of her daily recipes and making sure she’s getting enough protein and fiber—rather than relying on bland greens and chicken—has worked for her. “I’m a foodie,” Kings said. “It’s torture for me to eat the same thing every day.”
Natalie Casagrande, 31, was on the same weight-loss program as Kings, but Friedhoff and colleagues created a different approach for her. Casagrande’s weight has fluctuated for a long time. In order to lose weight quickly, she has tried many dangerous weight loss methods, such as deliberately starving and exercising for a long time. At one point, she shrunk from a size 14 to a size 0 in just a few months. At the time of signing up for the institute’s weight loss program, Casagrande weighed 173 pounds and had a BMI greater than 30, which means she is obese.
After starting to lose weight under the guidance of the staff, Casagrande also recorded her daily food intake, but unlike Kings, she did not enjoy the process. What she really loves is sports, which she can add to her schedule at any time and is very motivated. After speaking with a psychologist at the institute, Casagrande learned that she suffers from a chronic anxiety disorder, which is why she is emotionally eating.
Casagrande tried three times in three years to lose weight. During one rebound, she gained 10 pounds. She adjusted her plan to focus on mental health, and then tried again to lose weight. Today, she weighs 116 pounds and has maintained it for a year. “It takes trial and error to find what works best for you,” she said. “Not every day is perfect, but I’m able to achieve my goals because I’ve been through tough days.”
Knowing what is most important to each individual is more important than finding a one-size-fits-all recipe, Friedhoff said. “If we continue to recommend those types of diets to people without considering each individual’s specific circumstances, we could be in trouble,” he said. As a result, he mostly talks with patients about their daily lives, socioeconomics, and so on. Status and mental health. “Unfortunately, this is not the norm. Many physicians are not doing enough to understand their patients,” he said.
Friedhoff and Hall co-authored an article in The Lancet calling on the scientific community to focus research on how to help people maintain healthy lifestyles, rather than finding diet recipes. They wrote: “The hype of a recipe when it has little effect only overstates the importance of the recipe and does nothing to help it.”
Scientists still don’t understand why the same recipe can have different effects on different people. “This is the biggest unsolved mystery in the field,” Hall said. “If only I knew the answer.”
Some believe the answer lies in genes. Over the past few years, researchers have identified nearly 100 genetic markers that appear to be associated with obesity or being overweight, and for some populations, genes do play an important role in breaking down calories and storing fat. But experts believe that the genes that make people prone to obesity existed 30 or even 100 years ago, meaning that genes are not sufficient to explain the rapid rise in obesity rates in recent years.
In addition, a 2017 study found that whether a person carries the obesity gene has no effect on that person’s ability to lose weight. “We think this is good news,” said John Mathers, a professor of human nutrition at Newcastle University in the UK. “Having the obesity gene may make you fatter, but it won’t affect your weight loss.”
Some scientists are also exploring the relationship between obesity and everyday chemicals, such as diphenol-based propane in can coatings and cash register receipts, flame retardants in sofas and mattresses, and insecticides in food. agent residues and phthalates in plastics and cosmetics. What these chemicals have in common is that they mimic hormones in the human body. Some scientists worry that they may disrupt hormones and metabolism, damage our fragile endocrine system, and lead to fat accumulation.
Scientists are investigating another question: Does the microbiome, the trillions of bacteria that live in the human body and on the skin’s surface, influence the body’s metabolism of certain foods? According to Ilan Ilenav and Ilan Siegel, researchers in the Personalized Nutrition Program at the Weizmann Institute of Science in Israel, the reason why weight loss diets work differently for different people may be that the microbiome in the human body responds to different Food reacts differently.
In a 2015 study, Siegel and Elenaf distributed measuring devices to 800 subjects and asked them to check their blood sugar every five minutes for a week. The subjects filled out a questionnaire about their health status. The researchers collected their blood and stool samples, sequenced their microbiomes, and recorded their diet, sleep and exercise using a mobile phone app.
The study found that blood sugar levels in the subjects’ bodies varied widely after meals, even when they ate exactly the same thing. This suggests that general dietary advice is meaningless. “That surprised us,” Siegel said.
The researchers used the collected data to develop an algorithm for each subject that could accurately predict a person’s blood sugar response to a certain food based on the person’s microbiome. Therefore, Elenaf and Siegel believe that the next frontier in weight loss science lies in the gut. They believe that the algorithms they developed could eventually help doctors to prescribe highly personalized prescriptions based on how each individual responds to different foods.
Not surprisingly, some companies are already trying to put this idea into commercial practice. Some health supplement companies are peddling highly personalised probiotic tablets online, with customers reporting successful weight loss after taking the product. So far, though, studies proving probiotics have a weight-loss effect are sparse, as are genetic tests that claim to help you decide which diet is right for you.
When asked about their ideal body, many people want to lose three times the weight recommended by their doctors. This goal is too difficult to achieve, no wonder so many people simply give up weight loss. In fact, most people can improve their health without losing too much weight. Studies have shown that losing just 10% of your body weight can lead to significant improvements in blood pressure and blood sugar, as well as a reduced risk of heart disease and type 2 diabetes.
For Ottawa’s Kings, adjusting her expectations has helped her ultimately successfully lose weight in a healthy and sustainable way. She said she may have room to lose weight in the eyes of others, but she is currently at a healthy weight by doctors’ standards. “You have to accept that you’ll never be as weak as a model,” she said. “I’m just right now, and I’m satisfied.”
