10.7: Best Practices For Weight Management

With over 70% of Americans currently overweight or obese, it isn’t surprising that many individuals report engaging in weight management efforts.¹ In fact, a 2019 report from a national survey on current trends in weight loss attempts and strategies found that 42% of adults in the United States had recently attempted to lose weight, primarily through reduced food consumption and exercise.² In this unit we examine the best practices for weight management based on the body of evidence from many years of scientific research.

Figure \(\PageIndex{1}\): Adults enjoying a walk outside. "20150429-45[1]” by Obesity Canada is licensed under CC BY-NC-ND 2.0.

Biology Behind the Challenge of Weight Loss

We have just considered the gravity of the obesity problem in the US and worldwide. How is the US combating its weight problem on a national level, and have the approaches been successful? Successful weight loss is defined as individuals intentionally losing at least 10% of their body weight and keeping it off for at least one year.³ Results from some lifestyle intervention studies suggest that most individuals are not successful at long-term weight loss. Yet an evaluation of successful weight loss involving more than fourteen thousand participants published in the International Journal of Obesity estimated that more than one in six Americans, or 17%, who were overweight or obese were successful at both achieving and maintaining a significant level of weight loss.⁴ While this estimate is more promising than other studies suggest, it still raises the question: Why is achieving long-term weight loss so difficult? Much of the explanation lies in understanding the biology of weight loss.

Weight loss has often been viewed as a simple formula: energy in versus energy out. If you consume more calories than you expend, you gain weight. If you expend more calories than you consume, you lose weight. This is the general principle of energy balance, as discussed earlier in this chapter, and this principle gives foundation to the basic premise of weight management.

However, the body is more complex than a simple formula. And much like many functions within the body, weight is tightly regulated. To prevent perpetual weight loss or weight gain every time environmental or behavioral factors change, mechanisms within the body adjust to help normalize weight at a steady point.⁵ But our obesogenic environment often promotes behaviors that encourage excessive caloric intake and lower energy expenditure, leading to a higher steady weight over time. When an individual focuses on losing weight, active weight-loss efforts often yield initial weight loss. But those same mechanisms that work to maintain a steady weight also kick in during periods of weight loss to help the body defend the original weight.⁵ The body recognizes weight loss as a threat to survival, lowering basal metabolic rate to preserve calories and protect against starvation. Additionally, as someone loses weight, there is less physical mass to the body that has to be moved from place to place throughout the day, resulting in fewer calories burned through physical movement and activity and less metabolically active tissue using calories for fuel throughout the day.

Biological differences in individual metabolism may also impact weight loss success. Researchers have found that some individuals have a “thrifty” metabolism, meaning that they have a lower metabolic rate and expend significantly fewer calories when in a fasting (or calorie-restricted) state, common in weight loss efforts. This results in a lower level of weight loss. In contrast, individuals with a “spendthrift” metabolism tend to have a higher metabolic rate in a fasting state, burning more calories and thus yielding bigger weight loss results.⁶ According to researcher Martin Reinhardt, M.D., “The results corroborate the idea that some people who are obese may have to work harder to lose weight due to metabolic differences.”⁷

Figure \(\PageIndex{2}\): Illustration of the concept of spendthrift and thrifty metabolisms, characterized by their response to overfeeding and fasting.⁶

To add to the challenge of metabolic differences, research also suggests that changes in hormone levels due to weight loss may impact the body’s ability to maintain a lower weight. Decreases in thyroid hormones that regulate metabolism, as well as changes in hormones such as leptin and insulin that affect satiety levels, contribute to the challenge of maintaining a lower weight after initial weight loss occurs.^5,8 In individuals maintaining a 10% or greater weight loss, all of these changes combine to account for an estimated decrease of 300-400 calories in energy expenditure per day beyond what is expected due to the change in body composition alone.⁸ These biological factors and their influence on weight are discussed further in the following video.

Video \(\PageIndex{1}\): The Quest to Understand the Biology of Weight Loss.⁹ (22:52 minutes)

Evidence-Based Approaches to Weight Loss

Despite the challenges imposed by biological processes in the body, there is significant evidence to suggest that successful weight loss and maintenance is possible. There are many approaches when considering options for weight loss, and no single treatment is right for everyone. In fact, while following a lower-calorie healthy eating plan is often the first approach to weight loss, research shows that there is no single dietary strategy that is superior to others. ^10,11 For example, a recent trial, called the DIETFITS study, followed participants on either a low-fat or low-carbohydrate diet for one year and found no significant difference in weight loss between study groups. And both dietary strategies produced a range of weight loss results, with some participants losing over 60 pounds and others gaining 20 pounds over the course of the year, suggesting that what works for one individual may produce varying results in others.¹

Figure \(\PageIndex{3}\): Results from the DIETFITS study show that, regardless of the type of diet followed, participants experienced a similar wide range of changes in weight.¹¹

To learn more about the DIETFITS study, check out the following video.

Video \(\PageIndex{2}\): Stanford’s Christopher Gardner Tackles the Low-Carb vs. Low-Fat Question.¹² by Stanford Medicine. (4:08 minutes).

The National Weight Control Registry (NWCR) has tracked over ten thousand people who have been successful in losing at least 30 pounds and maintaining this weight loss for at least one year. Their research findings show that 98% of participants in the registry modified their food intake, and 94% increased their physical activity, mainly by walking.⁹

Although NWCR members took a great variety of approaches to achieve successful weight loss, most have reported that their approach involved adhering to a low-calorie, low-fat diet and doing high levels of activity (about one hour of exercise per day). Moreover, most members eat breakfast every day, watch fewer than ten hours of television per week, and weigh themselves at least once per week. About half of them lost weight on their own, and the other half used some type of weight-loss program.¹³  In most scientific studies, successful weight loss is accomplished only by changing the diet and increasing physical activity together. Doing one without the other limits the amount of weight lost and the length of time that weight loss is sustained.¹⁴

Evidence-Based Dietary Recommendations

The 2020-2025 Dietary Guidelines for Americans offers specific, evidence-based recommendations for dietary changes aimed at keeping calorie intake in balance with physical activity, which is key for weight management.¹⁵  These recommendations include following a healthy eating pattern that accounts for all foods and beverages within an appropriate calorie level, including the following:

• A variety of vegetables from all of the subgroups—dark green, red, and orange, legumes (beans and peas), and starchy
• Fruits, especially whole fruits
• Grains, at least half of which are whole grains
• Fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortified soy beverages and yogurts
• A variety of protein foods, including seafood, lean meats and poultry, eggs, legumes (beans and peas), nuts, seeds, and soy products
• Oils, including vegetable oils, and oils from nuts, seeds, and seafood

A healthy eating pattern limits

• Saturated fats and trans fats
• Added sugars
• Sodium
• Alcohol. If alcohol is consumed, it should be limited—no more than one drink or less per day for women and two drinks per day or fewer for men—and only by adults of legal drinking age. Pregnant women should not drink alcohol.

While these guidelines establish basic recommendations for dietary intake across all food groups, most Americans fall short of achieving these recommendations. Figure 10.7.4 shows how Americans are falling short of meeting the Dietary Guidelines.

Figure \(\PageIndex{4}\): The Healthy Eating Index is based on 100 points. American scores per age group range from 51 to 61.¹⁵ "Adherence of the US Population to the Dietary Guidelines Across Life Stages, as Measured by Average Total Healthy Eating Index-2015 Scores" from Dietary Guidelines for Americans, 2020-2025 by the US Department of Agriculture is in the Public Domain.

Evidence-Based Physical Activity Recommendations

The other part of the energy balance equation is physical activity. The Dietary Guidelines are complemented by the 2018 Physical Activity Guidelines for Americans, issued by the Department of Health and Human Services (HHS) in an effort to provide evidence-based guidelines for appropriate physical activity levels. These guidelines provide recommendations to Americans aged three and older about how to improve health and reduce chronic disease risk through physical activity. Increased physical activity has been found to lower the risk of heart disease, stroke, high blood pressure, Type 2 diabetes, colon, breast, and lung cancer, falls and fractures, depression, and early death. Increased physical activity not only reduces disease risk, but also improves overall health by increasing cardiovascular and muscular fitness, increasing bone density and strength, improving cognitive function, and assisting in weight loss and weight maintenance.¹⁶

The key guidelines for adults include the following:

• Adults should move more and sit less throughout the day. Some physical activity is better than none. Adults who sit less and do any amount of moderate-to-vigorous physical activity gain some health benefits.
• For substantial health benefits, adults should do at least 150 minutes (2 hours and 30 minutes) to 300 minutes (5 hours) per week of moderate-intensity aerobic activity, or 75 minutes (1 hour and 15 minutes) to 150 minutes (2 hours and 30 minutes) per week of vigorous-intensity aerobic physical activity, or an equivalent combination of moderate- and vigorous-intensity aerobic activity .
• Preferably, aerobic activity should be spread throughout the week.
• Engaging in physical activity beyond the equivalent of 300 minutes (5 hours) of moderate-intensity physical activity per week can result in additional health benefits and may help with weight loss and weight loss maintenance.
• Adults should also do muscle-strengthening activities of at least moderate intensity that involve all major muscle groups on 2 or more days per week, as these activities provide additional health benefits. Exercises such as push-ups, sit-ups, squats, and lifting weights are all examples of muscle-strengthening activities.

The 2018 Physical Activity Guidelines broadly classify moderate physical activities as those when you “can talk, but not sing, during the activity” and vigorous activities as those when you “cannot say more than a few words without pausing for a breath.” ¹⁶  Despite the indisputable benefits of regular physical activity, a 2018 report from the American Heart Association estimates that 8 out of 10 Americans do not meet these guidelines.²

Figure \(\PageIndex{5}\): The 2018 Physical Activity Guidelines’ definition of moderate-intensity and vigorous-intensity exercise. "Exercise Intensity" from Physical Activity Guidelines for Americans, 2nd. ed. by the US Department of Health and Human Services is in the Public Domain.

Given the number of Americans who are falling short on both nutrition and physical activity recommendations, it is easy to see that these two areas of behavior are of primary interest in improving the health and weight of our nation.

Evidence-Based Behavioral Recommendations

Behavioral weight loss interventions have been described as approaches “used to help individuals develop a set of skills to achieve a healthier weight. It is more than helping people to decide what to change; it is helping them identify how to change.” ¹⁷ Cornerstones for these interventions typically include self-monitoring through daily recording of food intake and exercise, nutrition education and dietary changes, physical activity goals, and behavior modification.¹⁸ Research shows that these types of interventions can result in weight loss and a lower risk for type 2 diabetes, and similar maintenance strategies lead to less weight regained later.¹⁹

Behavioral interventions have been shown to help individuals achieve and maintain weight loss of at least 5% from baseline weight. The Food and Drug Administration (FDA) considers a 5% weight loss to be clinically significant, as this level of weight loss has been shown to improve cardiometabolic risk factors such as blood lipid levels and insulin sensitivity.^18,19 The behavioral intervention team often includes primary care clinicians, dietitians, psychologists, behavioral therapists, exercise physiologists, and lifestyle coaches. These programs may include a variety of delivery methods, often through group classes of 10-20 participants both in-person and online, and may use print-based or technology-based materials and resources. The interventions usually span one to two years, with more frequent contact in the initial months (weekly to bi-monthly) followed by less frequent contact (monthly) in the latter months or maintenance phase.¹⁹ A variety of behavioral topics are covered throughout the program and range from nutrition education and goal-setting to problem-solving and assertiveness. Relapse prevention is included as participants move into the maintenance phase.²⁰

Figure \(\PageIndex{6}\): Common topics included in behavioral interventions for weight loss. "Behavioral Weight-Loss Treatment Topics" by Heather Leonard is licensed under CC BY 4.0.

Pharmacotherapy and Bariatric Surgery

In some situations, lifestyle changes in diet, exercise, and behavior modification are not enough to produce meaningful levels of weight loss, and the use of medications may be considered to improve weight loss outcomes. The use of medications is recommended in conjunction with, and not in place of, lifestyle changes. Medications are typically considered for individuals with a BMI over 30, or BMI over 27 with at least one coexisting condition, such as heart disease, type 2 diabetes, or hypertension. Only medications approved by the FDA for weight loss should be used.²¹  Over-the-counter weight loss supplements are not monitored by the FDA and are not recommended because of safety concerns.

Surgical interventions may be appropriate for individuals with a BMI over 40 or BMI over 35 with obesity-related coexisting conditions if behavioral interventions (with or without medication) have not been effective. Potential candidates for surgery should be referred to an experienced bariatric surgeon for consultation and evaluation.²¹

Non-Diet Approaches

In addition to weight management approaches that focus on the energy balance equation through dietary changes, physical activity programs, and behavioral interventions, there is a growing movement for non-diet approaches for a healthier mentality toward weight, food, and body image. These approaches focus on establishing healthier relationships with food and more body acceptance and positivity regardless of shape and size. Many of these programs seek to normalize relationships with food, make eating an enjoyable experience focused on well-being rather than dieting, do away with shame or guilt often associated with failed weight loss efforts, and promote respect and inclusivity for all people regardless of weight or size. Mindful eating or intuitive eating are common components of these approaches.

Figure \(\PageIndex{7}\): Body positivity activities can support a healthier perspective on body image. "Stop Bullying" by Lucky Lynda is licensed under CC BY 2.0.

One of these approaches, the Satter Eating Competence Model, is based on four components: eating attitudes, food acceptance, regulation of food intake and body weight, and management of the eating context. According to Ellyn Satter, a registered dietitian and family therapist and the founder of the model, competent eaters are “confident, comfortable, and flexible with eating and are matter-of-fact and reliable about getting enough to eat of enjoyable and nourishing food.” ²²  This approach enhances “the importance of eating by making it positive, joyful, and intrinsically rewarding.” ²² This model emphasizes that by developing a healthier relationship with food, individuals will yield the following benefits:²³

• Have better diets
• Feel more positive about food and eating
• Have better overall health
• Have the same or lower BMI
• Sleep better
• Be more active
• Have better physical self-acceptance
• Be more trusting of themselves and others

Health at Every Size (HAES) is another movement started by the Association for Size Diversity and Health organization as an alternative to weight-centered health models. HAES aims to decrease our culture’s obsession with body size and weight, decrease weight discrimination and stigma, and instead promote size acceptance and inclusivity.²⁴ Key principles of the HAES approach include:

• Acceptance and respect for the inherent diversity of body shapes and sizes
• Health enhancement through policies and services that promote well-being in all aspects of health, including physical, economic, social, emotional, and spiritual needs
• Respectful care and elimination of weight bias and discrimination through proper education and training
• Eating behaviors driven by hunger, satiety, nutritional needs, and pleasure instead of external regulation by diets and eating plans
• Physical activity through life-enhancing movement for all sizes and abilities

In summary, managing the energy balance equation is complicated but not impossible. Take some time to consider the many behaviors to prioritize steps toward a healthier body. Considering how each of the Dimensions of Wellness contributes to your current behaviors is a great place to start!

Attributions:

• University of Hawai‘i at Mānoa Food Science and Human Nutrition Program, “Dietary, Behavioral, and Physical Activity Recommendations for Weight Management,” CC BY-NC 4.0

References:

1. Obesity and Overweight. Centers for Disease Control and Prevention. Updated January 5, 2023. Accessed November 13, 2019. https://www.cdc.gov/nchs/fastats/obesity-overweight.htm.
2. Han L, You D, Zeng F, et al. Trends in self-perceived weight status, weight loss attempts, and weight loss strategies among adults in the United States, 1999-2006. JAMA Netw Open. 2019;2(12):e1915219. doi:10.1001/jamanetworkopen.2019.15219.
3. Wing RR, Hill JO. Successful weight loss maintenance. Annu Rev Nutr. 2001;21:323-341. doi:10.1146/annurev.nutr.21.1.323.
4. Kraschnewski JL, Boan J, Esposito J, et al. Long-term weight loss maintenance in the United States. Int J Obes. 2010;34(11):1644-1654. doi:10.1038/ijo.2010.94.
5. MacLean PS, Bergouignan A, Cornier MA, Jackman MR. Biology’s response to dieting: the impetus for weight regain. Am J Physiol Regul Integr Comp Physiol. 2011;301(3):R581-R600. doi:10.1152/ajpregu.00755.2010.
6. Reinhardt M, Thearle MS, Ibrahim M, et al. A human thrifty phenotype associated with less weight loss during caloric restriction. Diabetes. 2015;64(8):2859-2867. doi:10.2337/db14-1881.
7. NIH: National Institute of Diabetes and Digestive and Kidney Diseases. Ease of weight loss influenced by individual biology. ScienceDaily. May 11, 2015. Accessed November 11, 2019. https://www.sciencedaily.com/releases/2015/05/150511162918.htm.
8. Rosenbaum M, Kissileff HR, Mayer LE, Hirsch J, Leibel RL. Energy intake in weight-reduced humans. Brain Res. 2010;1350:95-102. doi:10.1016/j.brainres.2010.05.062.
9. HBO Docs. The Quest to Understand the Biology of Weight Loss [Video]. YouTube. Published May 14, 2012. Accessed April 18, 2019. https://youtu.be/2i_cmltmQ6A?si=4Forn4AyQZ2b8UNu.
10. Treatment for overweight & obesity. National Institute of Diabetes and Digestive and Kidney Diseases. Updated May 2023. Accessed November 3, 2023. https://www.niddk.nih.gov/health-information/weight-management/adult-overweight-obesity/treatment.
11. Gardner CD, Trepanowski JF, Del Gobbo LC, et al. Effect of low-fat vs low-carbohydrate diet on 12-month weight loss in overweight adults and the association with genotype pattern or insulin secretion: the DIETFITS randomized clinical trial. JAMA. 2018;319(7):667-679. doi:10.1001/jama.2018.0245.
12. Stanford Medicine. Stanford’s Christopher Gardner Tackles the Low-Carb vs. Low-Fat Question [Video]. YouTube. Published February 19, 2018. Accessed May 25, 2022. https://youtu.be/hZ76Cg-Emw8?si=4_KPC1SYPlkR4DtV.
13. The National Weight Control Registry. Accessed November 8, 2019. https://www.nwcronline.com/join.aspx.
14. NHLBI Obesity Education Initiative Expert Panel on the Identification, Evaluation, and Treatment of Obesity in Adults. Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults: The Evidence Report. National Institutes of Health: National Heart, Lung, and Blood Institute; 1998:51S–210S. Accessed November 8, 2023. https://www.ncbi.nlm.nih.gov/books/NBK2003/.
15. Dietary Guidelines for Americans 2020-2025. Make Every Bite Count With the Dietary Guidelines. dietaryguidelines.gov. Published December 2020. Accessed July 27, 2023. https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf. https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf.
16. United States Department of Health and Human Services. Physical Activity Guidelines for Americans. 2nd ed. US Department of Health and Human Services; 2018. Accessed November 3, 2023. https://health.gov/sites/default/files/2019-09/Physical_Activity_Guidelines_2nd_edition.pdf.
17. National Academies of Sciences, Engineering, and Medicine. The Challenge of Treating Obesity and Overweight: Proceedings of a Workshop. The National Academies Press; 2017. Accessed November 13, 2023. https://pubmed.ncbi.nlm.nih.gov/29341559/.
18. Smith CE, Wing RR. New directions in behavioral weight-loss programs. Diabetes Spectr. 2000;13(3):142-148. https://www.proquest.com/openview/acd5b25327d8cfbdcebc2f367a654d65/1?pq-origsite=gscholar&cbl=37012.
19. US Preventive Services Task Force, Curry SJ, Krist AH, et al. Behavioral weight loss interventions to prevent obesity-related morbidity and mortality in adults: US Preventive Services Task Force recommendation statement. JAMA. 2018;320(11):1163-1171. doi:10.1001/jama.2018.13022.
20. Donnelly JE, Blair SN, Jakicic JM, et al. American College of Sports Medicine Position Stand. Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults. Med Sci Sports Exerc. 2009;41(2):459-471. doi:10.1249/MSS.0b013e3181949333.
21. Jensen MD, Ryan DH, Apovian CM, et al. 2013 AHA/ACC/TOS guideline for the management of overweight and obesity in adults: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and The Obesity Society [published correction appears in Circulation. 2014 Jun 24;129(25 Suppl 2):S139-40]. Circulation. 2014;129(25 Suppl 2):S102-S138. doi:10.1161/01.cir.0000437739.71477.ee.
22. Satter E. Eating competence: nutrition education with the Satter Eating Competence Model. J Nutr Educ Behav. 2007;39(5 Suppl):S189-S194. doi:10.1016/j.jneb.2007.04.177.
23. Ellyn Satter Institute. The Satter Eating Competence Model. Accessed November 5, 2023. https://www.ellynsatterinstitute.org/satter-eating-competence-model/.
24. The Health at Every Size Principles. Association for Size Diversity and Health. Updated 2013. Accessed November 2, 2023. https://asdah.org/haes/.