The science and practice of weight loss and weight loss maintenance are changing faster than ever. Seemingly, each month now brings new research, new treatment options, and new expectations. The role of psychology, however, remains as important and abiding as ever to people’s long-term weight loss success. This post describes six psychology principles that contribute the most to effective weight loss maintenance in the modern era of medicine-assisted therapy.
Background
In August 2025, pharmaceutical company Eli Lilly released new results from the Attain-1 study. Attain-1 is a Phase 3 clinical trial testing the effects of a daily weight loss pill called orforglipron.1 Although the weight loss results from orforglipron fell short of standards set by injectable GLP-1 medicines, the average weight loss experienced by participants was still two to three times greater than any previous weight loss pill. If, as expected, this medicine becomes FDA-approved in 2026, people struggling with conditions such as overweight, obesity, and weight-related metabolic health conditions will have access to an increasing range of treatments for achieving a level of weight loss once observed mostly from bariatric surgeries.
No matter how impressive, weight loss, however, is only the beginning. The Holy Grail of weight loss remains sustainability. This new era of medication-assisted treatment only makes the stubborn challenge of long-term weight loss more critical to address.2
As recently as the 1990s, maintaining weight loss of 30 or more pounds for at least a year was so unusual that it qualified a person for the National Weight Loss Registry.3 Tracking the behavior patterns of people in the registry became the empirical basis for an entire generation of healthcare providers making recommendations about weight loss maintenance. Eating breakfast, daily weighing, obtaining one-plus-hours-a-day of exercise, and reducing TV viewing time are each recommendations drawn from registry participants achieving lasting weight loss.4 But that was from an era when significant and sustained weight loss was rare and achieved mostly through lifestyle changes alone.
What happens when medicines allow us to help people achieve transformational weight loss, the kind that improves both health and quality of life, at the scale of millions? Will we see a repeat of the weight loss-weight regain cycle that dominated the diet and exercise era, or can we create a new era where successful weight loss maintenance becomes as routine as the initial weight loss?
Existing evidence, unfortunately, suggests that even the powerful new GLP-1 weight loss medicines themselves are not sufficient for long-term weight loss.2 But by combining these potent new treatments with proven principles from psychology, weight loss in perpetuity becomes possible.5
Six psychological factors critical to effective weight loss maintenance
Just as the medical treatments for weight loss have changed, so too has the role of psychology. From the old emphasis on factors such as motivation, emotional eating, calorie tracking, and portion control, the new psychology emphasis is increasingly on sustainability factors such as long-term values, supportive environments and lifestyles, identity change, and quality-of-life goals. Figures 1 and 2 illustrate six psychological principles that, for many people, contribute the most to their long-term weight loss success.
Because no two people are the same, however, don’t feel compelled to apply these principles uniformly. For some people, addressing just a subset of the six will suffice to empower their weight loss, whereas others will benefit from attention to more. The relative order of importance of these six principles will vary not only from person to person, but also across time and circumstances, even for the same person. Let your principles and strategies evolve in parallel with your journey.
Ultimately, the greatest value in these six psychology weight loss maintenance principles help individuals identify which are most important to them. And for fostering creative discussions about where and how to apply them for maximum leverage.
If you’re one of the growing number of people who’ve committed to healthy weight loss, seized the latest weight loss treatment opportunities, and made the critical lifestyle changes for your initial results, are you ready to take it to the next level and enjoy the rewards of lifelong weight management?