Emory Magazine | Winter 2024
Weighing in on Weight Loss
Emory experts debunk popular fads and share proven, science-based tactics — including the many benefits of taking Ozempic or Wegovy — for improving your diet, fitness and overall health long-term.
By Martha Nolan
If you think losing weight — and keeping it off — is hard, you are absolutely right. You are also not alone.
The vast majority of people who manage to lose weight through a period of focused dieting and exercise put some or all of it back on within a year. That’s because so many weight-loss strategies, such as restrictive diets and intense exercise regimens, are just not sustainable over time.
The whole process of weight loss has become more confusing than ever, thanks to the sheer volume of information available — some factual and some not-so-much. From social media influencers touting miracle weight-loss hacks to the latest research studies that seem to contradict yesterday’s health advice, it’s hard to know what or who to believe.
“Obesity is a chronic medical condition and being overweight can be a health concern for some people,” says Sheethal Reddy, a licensed psychologist at the Emory Bariatric Center at Midtown.
“But weight problems are not treated like other chronic health problems. If you have been diagnosed with heart disease, it’s unlikely you’d be taking advice from a co-worker. You would likely go to your cardiologist. But with weight loss, everyone is an expert. There is so much information out there — much of it questionable — that I think it can be hard to separate the fluff from evidence-backed strategies that work.”
Never fear, experts from Emory School of Medicine, Rollins School of Public Health, Nell Hodgson Woodruff School of Nursing and Emory Healthcare are here to take a look at those evidence-backed strategies and help you identify what may work best for you.
THE NUMBER ON THE SCALE
From a purely biological perspective, losing weight should be straightforward. A pound of fat is 3,500 calories, so creating a 3,500-calorie deficit will lead to a pound of weight loss. However, taking that pound off is a different experience for everyone. Many factors beyond our diet and exercise can affect appetite hormones, and hence our hunger and satiety levels. Genetic traits also influence factors like how much pleasure, flavor and satiety we get from food.
“Telling people to reduce their calories by 500 a day is not so simple for everyone,” says Sharon Bergquist, Pam R. Rollins Professor of Medicine and an internal medicine physician. “We are dealing with something far more powerful than willpower.”
"You can be healthy and obese, and you can be unhealthy and thin. We need to move toward a more holistic view of health, not just weight."
And, at the end of the day, the number on the scale is not the be-all-end-all if you want to maximize your health. “You can be healthy and obese, and you can be unhealthy and thin,” says Bergquist. “We need to move toward a more holistic view of health, not just weight.”
Bergquist is referring to metabolic health, which is measured with five factors: blood pressure, cholesterol, triglycerides, blood sugar and waist circumference. If someone has three or more factors outside of the recommended range, they have metabolic syndrome, which increases the risk for a host of diseases, including cancer, heart disease, diabetes and dementia.
Elevated weight and BMI (body mass index) certainly can be indicators of problems in one or more of these areas, but a more meaningful proxy is waist-to-height ratio. Basically, if your waist circumference is more than half of your height, you are at elevated risk for metabolic syndrome, according to the National Institutes of Health.
That’s because unlike fat that sits underneath your skin, which is more or less inert, belly fat — or visceral fat — wraps around your organs. It goes beyond just being excess weight; research shows that it actively disrupts the body’s metabolic processes, promotes chronic inflammation and increases the risk of numerous serious health conditions, particularly heart disease, diabetes and certain cancers.
So while you’ll undoubtedly want to keep an eye on your weight and BMI during your weight loss and improved health journey, you would also be well served to monitor your waist-height ratio.
FAD DIETS VS. WHOLE FOODS
Every so often, a new hot diet will come along and take everyone by storm. Laurence Sperling has seen them all. The Katz Professor in Preventive Cardiology and founder of the Emory Center for Heart Disease Prevention, Sperling has served for the past 15 years as an expert on U.S. News & World Report’s annual ranking of the best diets.
What he has seen again and again is that the hot fad diets — think Keto, Paleo, Atkins — can result in rapid weight loss. But due to their highly restrictive nature, the diets tend to be unsustainable, and the weight comes piling back on, Sperling says.
The diets that consistently rank toward the top of the list — Mediterranean Diet, DASH Diet, MIND Diet — have a key element in common. They all focus on consuming whole, unprocessed, predominantly plant-based foods.
It seems simple, but it’s a heavy lift for many Americans. Today, more than half of the calories we consume come from ultraprocessed foods, according to an 18-year study published in the American Journal of Clinical Nutrition. And these calorie-dense, nutrient-poor foods trigger dopamine release, which leaves you craving even more of them. On the other hand, unprocessed, whole foods tend to be nutrient-rich and higher in fiber, which results in natural calorie control. “How many people binge on broccoli?” asks Sperling.
If you find following a prescribed diet, such as DASH or MIND, easiest for you, go for it. Otherwise, experts advise concentrating on eating whole foods, with an emphasis on fruits and vegetables. Sperling and other diet experts think this focus on eating whole foods is a more sustainable choice over your lifetime than trying to adhere to a particular diet.
Finding the right balance and quantity of those whole foods is difficult. Holley Nash, a registered dietitian nutritionist and nutrition education coordinator at the Emory Healthcare Bariatric Center, favors a method called the real food plate. Half of the plate is filled with fruits and nonstarchy vegetables, and Nash recommends aiming for color and variety. A quarter of the plate is reserved for whole grains and starchy vegetables, and the remaining quarter is for a lean protein serving of three to four ounces. “That is an easy, visual way to make sure you are getting the correct balance of nutrients,” Nash says.
FASTING FOR CELLULAR HEALTH
Some consider intermittent fasting a type of fad diet. Indeed, the practice of condensing meal consumption to certain periods of the day and fasting for the rest has been getting a lot of press lately.
It’s not for everyone. People who are under 18, pregnant, nursing or with a history of an eating disorder are discouraged from intermittent fasting. However, many lifestyle physicians praise the practice, particularly if you are eating healthy, whole foods during your consumption window. In fact, intermittent fasting can not only help with weight loss, it can improve health right down to the cellular level.
From a weight-loss perspective, intermittent fasting takes advantage of our body’s natural healing systems. Our bodies store glucose in the form of glycogen with enough reserves to last 12 to 24 hours depending on factors such as activity level and metabolic rate, according to the study “Effects of Intermittent Fasting on Health, Aging and Disease,” published in the New England Journal of Medicine. As glycogen is depleted, this research shows, our bodies shift to using fat in the form of ketones. So if you limit your eating to an eight-hour window, for example, you may primarily be burning fat for energy for up to four hours every day.
"When you're in a fasting state, your cells do the housecleaning. They repair damaged DNA. They repair damaged proteins. They also activate the growth of new mitochondria, which is the part of a cell that controls our metabolism."
That’s good news for your waistline, but it’s also good news for your cells. That’s because ketones are signaling molecules, and when they are released, they signal cells to switch from a growth state to a repair state. “When you’re in a fasting state, your cells do their housecleaning,” says Bergquist. “They repair damaged DNA. They repair damaged proteins. They also activate the growth of new mitochondria, which is the part of a cell that controls our metabolism.”
Bergquist continues: “So above and beyond calorie balance, fasting makes cells more efficient, more insulin sensitive and just healthier. And if you look at the most upstream factor leading to chronic disease, it’s cellular health. Damage to our cells is what ultimately manifests into disease. I personally think time-restricted eating — fasting for 12, or ideally closer to 14 hours a day and consuming most of your calories earlier in the day to align with your circadian rhythm — is an effective and sustainable way to improve your health.” That eating pattern, she says, is actually normal for our bodies rather than eating throughout our waking hours.
MOVE IT, MOVE IT
If all the benefits of exercise could be packaged into a pill, it would be the most widely used drug in the world, or so the saying goes. In addition to burning calories and helping maintain a healthy weight, regular exercise can boost your mood though the release of endorphins, improve your sleep, speed your recovery and lower the risk of myriad chronic diseases.
Recommendations are straightforward. The U.S. Department of Health and Human Services recommends getting a minimum of 150 minutes of moderate aerobic activity, or 75 minutes of vigorous aerobic activity, each week. If you want to lose weight, or keep off lost weight, it’s recommended that you increase that number to 300 minutes per week of moderate exercise or 150 minutes of vigorous exercise. You can break up the segments of physical activity any way you like.
“We used to think being a ‘weekend warrior’ had lower health benefits, but in fact the data shows that as long as you meet the 150 minutes per week, you get the bulk of the health benefits,” says Felipe Lobelo, associate professor of global health at the Rollins School of Public Health. “On the flip side, it doesn’t matter if you break it up into five- or 10-minute increments. You just have to get those 150 minutes in.”
You should also do strength-training exercises for all major muscle groups at least two times a week. Lobelo recommends using a weight or resistance level heavy enough to tire your muscles after about 12–15 repetitions.
"Most of our energy expenditure comes from nonexercise activities, and you can’t overcome the harm of being sedentary by exercising an hour a day. It comes down to the fact that our bodies were designed to move, and when they don’t, bad things happen."
Only about one quarter of Americans meet these requirements, according to a 2020 National Health Interview Survey. The National Health Interview Survey is one of the major data collection programs of the National Center for Health Statistics, which is part of the Centers for Disease Control and Prevention (CDC). And even those who do may not be moving enough the rest of the time. Indeed, if you hit the 300 minutes of exercise-per-week goal, but you sit on the couch for the other 9,780 minutes, your health will suffer.
“We need to move away from the mindset of ‘I worked out today, so I’m healthy,’” says Sperling. “Most of our energy expenditure comes from nonexercise activities, and you can’t overcome the harm of being sedentary by exercising an hour a day. It comes down to the fact that our bodies were designed to move, and when they don’t, bad things happen.”
As soon as you sit down, your calorie burning is reduced. Scientific studies show that with prolonged sitting, your major muscle groups, particularly in your legs and glutes, become inactive, which interferes with fat metabolism. Your body’s ability to regulate blood sugar declines, fueling glucose insensitivity. Overall, prolonged sitting has been linked to diabetes, heart disease, depression, dementia and multiple cancers.
Sperling and other experts recommend breaking up your sitting spells. If possible, get out of the chair every hour and move around for five minutes. You don’t need to do a sprint, just walk or move in any way. In everyday life, choose the path that requires more movement. Take the stairs instead of the elevator. Park at the back of the lot. Don’t take the moving sidewalk at the airport.
“The 10,000 steps a day recommendation is a good goal,” says Sperling. “But the most important thing is consistent movement throughout the day.”
There is another important component of fitness that you may have never heard of — cardiorespiratory fitness. It is basically the capacity of the body’s circulatory and respiratory systems to supply oxygen to the muscles during physical activity, and it’s a highly effective measure of overall health.
Cardiorespiratory fitness is commonly measured by VO2 max, which is the maximum rate at which someone can consume oxygen during intense exercise. “It’s a term that is rarely, if ever, heard during a clinical visit,” says Bergquist. “But there are literally thousands of clinical studies that show it is a better predictor of mortality than established risk factors such as smoking, hypertension, high cholesterol, cardiovascular disease and type 2 diabetes.”
To give you a sense of the magnitude, the risk of dying prematurely is 40% higher for someone who smokes than for a nonsmoker. And Bergquist notes, the risk of premature death is as much as five-fold higher for someone with poor cardiorespiratory fitness than for someone with an elite-level VO2 max, according to recent studies published in the Journal of the American Medical Association and the British Journal of Sports Medicine.
You can have your VO2 max measured by running on a treadmill while wearing a special face mask in your doctor’s office. Or you can measure it yourself with the Rockport One Mile Test, which you can find online. Basically, you walk as fast as you can for one (level) mile and measure your pulse at the end. There are formulas online where you can put in your age, your gender, the time it took you to do the mile and your heart rate at the end of the test and it will calculate your VO2 max.
“As physicians, we can make perhaps the biggest difference in our patients’ lives by encouraging cardio-respiratory fitness,” says Bergquist.
THE SIGNIFICANCE OF SLEEP
Many people don’t consider sleep when they are thinking about losing weight, but it is hugely important. “Sleep is a fundamental pillar of overall health and weight management, but it doesn’t get talked about enough,” says Rachel Annam, an internist and lifestyle medicine specialist at Emory Healthcare. “People who get less than seven hours of sleep a night have a higher risk for chronic diseases like diabetes and hypertension. They also have a harder time maintaining a healthy weight.”
That’s because poor sleep disrupts the hormones that regulate hunger. Leptin is a hormone that helps you feel full and rises during sleep. When you don't get enough sleep, your leptin levels decrease, which can make you feel hungrier and eat more. Ghrelin is a hormone that makes you feel hungry. Sleep deprivation can cause an increase in ghrelin levels, making you feel hungrier.
Inadequate sleep can also influence the reward centers in our brain, which can impact our decision-making around food choices, according to Annam. When we’re sleep-deprived, we’re more likely to consume less nutritious foods that are high in carbohydrates and fats. Several studies show that we’re also more prone to snacking between meals and experiencing nighttime cravings, consuming more calories than people who are not sleep-deprived.
Annam recommends developing healthy sleep habits that include going to bed and getting up at the same time every day — even on the weekend — to regulate your circadian rhythm, turning off all screens an hour or two before bedtime and striving to get seven to nine hours of sleep every night.
GAME-CHANGING DRUGS
Of course, the biggest news in weight loss these days are the new “miracle drugs,” like Ozempic, Wegovy and Rybelsus. Originally used to treat type 2 diabetes, these drugs — which use a glucagon-like peptide-1 receptor agonist (GLP-1RA) called a semaglutide as their main ingredient — are indeed game-changers in the weight-loss market.
“They are by far and away the biggest breakthrough in weight management that I’ve seen in my career,” says Angela Haynes Ferere, a family nurse practitioner and program director for the Distance Accelerated Bachelor of Science in Nursing program at the Nell Hodgson Woodruff School of Nursing. “And they have many more benefits besides weight loss.”
Ferere should know; she takes Wegovy herself. “I went through menopause and I developed long-haul COVID — my health was not good,” she said. “I was prehypertensive, prediabetic and had fatty liver disease. Then I started on Wegovy, and within months my lab values have all normalized.”
These GLP-1RA medications, which are available only by prescription, work on both physiological and psychological levels, according to Meghana Anugu, an internist and obesity medicine specialist at Emory Healthcare. They literally slow down your GI tract, so even when you eat a small amount, you feel full, she says.
Anugu explains they help stabilize blood-sugar levels by stimulating insulin release when blood sugar is high and inhibiting glucagon release, which prevents the liver from producing too much sugar. They also work on the reward-pleasure system to quiet the cravings or “food noise” that can lead to emotional eating, she says. And studies show that these drugs can reduce the risk of heart disease, kidney disease, cancer and dementia.
Like any medication, GLP-1RAs can have side effects. The most common are nausea, diarrhea, constipation and abdominal pain. They have also been associated with the risk of pancreatitis, gallstones and hypoglycemia. And, once you stop taking the drugs, you will typically regain much of the weight you have lost, says Anugu, who also is an assistant professor at Emory School of Medicine.
"There really weren’t good medications for weight control until GLP-1RAs (like Ozempic and Wegovy) were approved. They have shaken up the landscape of how we treat obesity."
“There really weren’t good medications for weight control until these GLP-1RAs were approved,” says Anugu. “These drugs have shaken up the landscape of how we treat obesity.”
That said, Anugu, Ferere and other weight-loss experts agree that drugs like Ozempic should be seen as just one tool — albeit a very effective one — for improving health and losing weight. “There are no magic bullets,” says Ferere. “These drugs need to be part of a comprehensive strategy to manage overall health, in addition to diet, exercise, sleep and stress management. To lose weight and maintain good health, you have to put the effort in.”
That means keeping your focus on common-sense health advice: incorporate more whole foods, such as fruits and vegetables, into your meals, and keep yourself moving throughout the day. Small changes, made consistently, can yield long-term benefits.
As we learn more about the relationship between food, movement and health, it’s important to stay informed while being wary of quick fixes or fad diets that promise unrealistic results. Above all, remember that health is personal and what works for one person may not work for another. Focus on sustainability, balance and what makes you feel good, both physically and mentally.
Photography Melissa Schollaert and courtesy of Laurence Sperling. Lead illustration ISpot.
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