Stop Trying Harder

Weight Loss After 40 in the Age of GLP-1  The Better Conditions Method

Stop Trying Harder draws on peer-reviewed research across GLP-1 medications, appetite and food noise, body composition and muscle health, menopause and midlife changes, sleep, behavior change, weight-loss maintenance, and the everyday conditions that can make consistency easier or harder.

This page gathers the scientific sources cited in the book for readers who would like to explore the evidence in more detail. Individual studies reflect specific populations, treatments, methods, and conditions and should not be interpreted as individualized medical, nutritional, or psychological advice.

Scientific Sources & References

GLP-1, Appetite & Food Noise

 

  • Arnaut T, Duncan S, Faurby M, et al. Retrospective assessment of food noise changes after initiation of injectable semaglutide for weight management in the USA: The INFORM Survey. Adv Ther. Published online May 30, 2026. doi:10.1007/s12325-026-03636-x.
  • Babazadeh D, Therrien S, Fitch AK, Steinberg FM. Changes in food cravings, dietary quality, body composition, and dietary intake during GLP-1 receptor agonist therapy: The CRAVE study. Obes Pillars. 2026;19:100292. doi:10.1016/j.obpill.2026.100292.
  • Blundell J, Finlayson G, Axelsen M, et al. Effects of once-weekly semaglutide on appetite, energy intake, control of eating, food preference and body weight in subjects with obesity. Diabetes Obes Metab. 2017;19(9):1242-1251. doi:10.1111/dom.12932.
  • de Vere Hunt I, Ramirez-Posada M, Babu CS, Brown-Johnson C, Linos E, Rodriguez F. Patient experiences with GLP-1 receptor agonists. JAMA Netw Open. 2026;9(6):e2616951. doi:10.1001/jamanetworkopen.2026.16951.
  • Diktas HE, Cardel MI, Foster GD, et al. Development and validation of the Food Noise Questionnaire. Obesity (Silver Spring). 2025;33(2):289-297. doi:10.1002/oby.24216.
  • Friedrichsen M, Breitschaft A, Tadayon S, Wizert A, Skovgaard D. The effect of semaglutide 2.4 mg once weekly on energy intake, appetite, control of eating, and gastric emptying in adults with obesity. Diabetes Obes Metab. 2021;23(3):754-762. doi:10.1111/dom.14280.
  • Heise T, DeVries JH, Urva S, et al. Tirzepatide reduces appetite, energy intake, and fat mass in people with type 2 diabetes. Diabetes Care. 2023;46(5):998-1004. doi:10.2337/dc22-1710.
  • Martin CK, Carmichael OT, Carnell S, et al. Tirzepatide on ingestive behavior in adults with overweight or obesity: A randomized 6-week phase 1 trial. Nat Med. 2025;31(9):3141-3150. doi:10.1038/s41591-025-03774-9.
  • Maselli D, Atieh J, Clark MM, et al. Effects of liraglutide on gastrointestinal functions and weight in obesity: A randomized clinical and pharmacogenomic trial. Obesity (Silver Spring). 2022;30(8):1608-1620. doi:10.1002/oby.23481.
  • Mozaffarian D, Agarwal M, Aggarwal M, et al. Nutritional priorities to support GLP-1 therapy for obesity: A joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and The Obesity Society. Obesity (Silver Spring). 2025;33(8):1475-1503. doi:10.1002/oby.24336. Corrigendum published 2026; doi:10.1002/oby.70222.
  • Tronieri JS, Wadden TA, Walsh O, et al. Effects of liraglutide on appetite, food preoccupation, and food liking: Results of a randomized controlled trial. Int J Obes (Lond). 2020;44(2):353-361. doi:10.1038/s41366-019-0348-6.
  • U.S. Food and Drug Administration. WEGOVY (semaglutide) injection and tablets: Full Prescribing Information. Revised February 2026. FDA AccessData.
  • U.S. Food and Drug Administration. ZEPBOUND (tirzepatide) injection: Full Prescribing Information. Revised February 2026. FDA AccessData.
  • Wharton S, Batterham RL, Bhatta M, et al. Two-year effect of semaglutide 2.4 mg on control of eating in adults with overweight/obesity: STEP 5. Obesity (Silver Spring). 2023;31(3):703-715. doi:10.1002/oby.23673.
  • Wharton S, Calanna S, Davies M, et al. Gastrointestinal tolerability of once-weekly semaglutide 2.4 mg in adults with overweight or obesity, and the relationship between gastrointestinal adverse events and weight loss. Diabetes Obes Metab. 2022;24(1):94-105. doi:10.1111/dom.14551.

 

Weight Loss, Body Composition & Muscle

 

  • Alissou M, Demangeat T, Folope V, et al. Impact of semaglutide on fat mass, lean mass and muscle function in patients with obesity: The SEMALEAN study. Diabetes Obes Metab. 2026;28(1):112-121. doi:10.1111/dom.70141.
  • Binmahfoz A, Dighriri A, Gray C, Gray SR. Effect of resistance exercise on body composition, muscle strength and cardiometabolic health during dietary weight loss in people living with overweight or obesity: A systematic review and meta-analysis. BMJ Open Sport Exerc Med. 2025;11(3):e002363. doi:10.1136/bmjsem-2024-002363.
  • Blatt AD, Roe LS, Rolls BJ. Increasing the protein content of meals and its effect on daily energy intake. J Am Diet Assoc. 2011;111(2):290-294. doi:10.1016/j.jada.2010.10.047.
  • Kim JE, O’Connor LE, Sands LP, Slebodnik MB, Campbell WW. Effects of dietary protein intake on body composition changes after weight loss in older adults: A systematic review and meta-analysis. Nutr Rev. 2016;74(3):210-224. doi:10.1093/nutrit/nuv065.
  • Laverde LP, Muñoz-Velandia OM, Alfonso D, Gómez Medina AM. Effect of GLP-1 receptor agonists at doses for obesity management on muscle health: Systematic review and meta-analysis of randomized controlled trials. Int J Obes (Lond). Published online June 19, 2026. doi:10.1038/s41366-026-02118-y.
  • Leidy HJ, Armstrong CLH, Tang M, Mattes RD, Campbell WW. The effects of consuming frequent, higher protein meals on appetite and satiety during weight loss in overweight/obese men. Obesity (Silver Spring). 2011;19(4):818-824. doi:10.1038/oby.2010.203.
  • Look M, Dunn JP, Kushner RF, et al. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study of adults with obesity or overweight. Diabetes Obes Metab. 2025;27(5):2720-2729. doi:10.1111/dom.16275.
  • Villareal DT, Aguirre L, Gurney AB, et al. Aerobic or resistance exercise, or both, in dieting obese older adults. N Engl J Med. 2017;376:1943-1955. doi:10.1056/NEJMoa1616338.

 

Midlife, Menopause, Sleep & Body Changes

 

  • Avis NE, Crawford SL, Greendale G, et al. Duration of menopausal vasomotor symptoms over the menopause transition. JAMA Intern Med. 2015;175(4):531-539. doi:10.1001/jamainternmed.2014.8063.
  • Bondarev D, Laakkonen EK, Finni T, et al. Physical performance during the menopausal transition and the role of physical activity. J Gerontol A Biol Sci Med Sci. 2021;76(9):1587-1594. doi:10.1093/gerona/glaa292.
  • Greendale GA, Sternfeld B, Huang MH, et al. Changes in body composition and weight during the menopause transition. JCI Insight. 2019;4(5):e124865. doi:10.1172/jci.insight.124865.
  • Harlow SD, Gass M, Hall JE, et al.; STRAW+10 Collaborative Group. Executive summary of the Stages of Reproductive Aging Workshop +10: Addressing the unfinished agenda of staging reproductive aging. J Clin Endocrinol Metab. 2012;97(4):1159-1168. doi:10.1210/jc.2011-3362.
  • Kravitz HM, Ganz PA, Bromberger J, et al. Sleep disturbance during the menopausal transition in a multi-ethnic community sample of women. Sleep. 2008;31(7):979-990. doi:10.5665/sleep/31.7.979.
  • Pontzer H, Yamada Y, Sagayama H, et al.; IAEA Doubly Labelled Water Database Consortium. Daily energy expenditure through the human life course. Science. 2021;373(6556):808-812. doi:10.1126/science.abe5017.
  • Sowers MF, Zheng H, Tomey K, et al. Changes in body composition in women over six years at midlife: Ovarian and chronological aging. J Clin Endocrinol Metab. 2007;92(3):895-901. doi:10.1210/jc.2006-1393.
  • St-Onge MP, Roberts AL, Chen J, et al. Short sleep duration increases energy intakes but does not change energy expenditure in normal-weight individuals. Am J Clin Nutr. 2011;94(2):410-416. doi:10.3945/ajcn.111.013904.
  • Sternfeld B, Wang H, Quesenberry CP Jr, et al. Physical activity and changes in weight and waist circumference in midlife women: Findings from the Study of Women’s Health Across the Nation. Am J Epidemiol. 2004;160(9):912-922. doi:10.1093/aje/kwh299.
  • Sun Y, Guardiano M, Saiki M, Li J. Alternative formulations of job strain and sleep disturbances: A longitudinal study in the United States. Am J Ind Med. 2025;68(3):264-272. doi:10.1002/ajim.23686.
  • Tasali E, Wroblewski K, Kahn E, Kilkus J, Schoeller DA. Effect of sleep extension on objectively assessed energy intake among adults with overweight in real-life settings: A randomized clinical trial. JAMA Intern Med. 2022;182(4):365-374. doi:10.1001/jamainternmed.2021.8098.

 

Eating Environment, Hunger & Food Choices

 

  • Block JP, He Y, Zaslavsky AM, Ding L, Ayanian JZ. Psychosocial stress and change in weight among US adults. Am J Epidemiol. 2009;170(2):181-192. doi:10.1093/aje/kwp104.
  • Flood-Obbagy JE, Rolls BJ. The effect of fruit in different forms on energy intake and satiety at a meal. Appetite. 2009;52(2):416-422. doi:10.1016/j.appet.2008.12.001.
  • Goldstein SP, Dochat C, Schumacher LM, et al. Using ecological momentary assessment to better understand dietary lapse types. Appetite. 2018;129:198-206. doi:10.1016/j.appet.2018.07.003.
  • Kegler MC, Hermstad A, Haardörfer R. Home food environment and associations with weight and diet among U.S. adults: A cross-sectional study. BMC Public Health. 2021;21:1032. doi:10.1186/s12889-021-11102-2.
  • Rolls BJ, Roe LS, Meengs JS. Salad and satiety: Energy density and portion size of a first-course salad affect energy intake at lunch. J Am Diet Assoc. 2004;104(10):1570-1576. doi:10.1016/j.jada.2004.07.001.
  • Thorndike AN, Gelsomin ED, McCurley JL, Levy DE. Calories purchased by hospital employees after implementation of a cafeteria traffic light-labeling and choice architecture program. JAMA Netw Open. 2019;2(7):e196789. doi:10.1001/jamanetworkopen.2019.6789.

 

Behavior Change, Habits & Consistency

 

  • Adriaanse MA, Vinkers CDW, De Ridder DTD, Hox JJ, De Wit JBF. Do implementation intentions help to eat a healthy diet? A systematic review and meta-analysis of the empirical evidence. Appetite. 2011;56(1):183-193. doi:10.1016/j.appet.2010.10.012.
  • Berry R, Kassavou A, Sutton S. Does self-monitoring diet and physical activity behaviors using digital technology support adults with obesity or overweight to lose weight? A systematic literature review with meta-analysis. Obes Rev. 2021;22(10):e13306. doi:10.1111/obr.13306.
  • König LM, Allmeta A, Christlein N, Van Emmenis M, Sutton S. A systematic review and meta-analysis of studies of reactivity to digital in-the-moment measurement of health behaviour. Health Psychol Rev. 2022;16(4):551-575. doi:10.1080/17437199.2022.2047096.
  • Kwasnicka D, Dombrowski SU, White M, Sniehotta FF. Theoretical explanations for maintenance of behaviour change: A systematic review of behaviour theories. Health Psychol Rev. 2016;10(3):277-296. doi:10.1080/17437199.2016.1151372.
  • Lally P, van Jaarsveld CHM, Potts HWW, Wardle J. How are habits formed: Modelling habit formation in the real world. Eur J Soc Psychol. 2010;40:998-1009. doi:10.1002/ejsp.674.
  • Milkman KL, Beshears J, Choi JJ, Laibson D, Madrian BC. Using implementation intentions prompts to enhance influenza vaccination rates. Proc Natl Acad Sci U S A. 2011;108(26):10415-10420. doi:10.1073/pnas.1103170108.
  • Patel ML, Cleare AE, Smith CM, Rosas LG, King AC. Detailed versus simplified dietary self-monitoring in a digital weight loss intervention among racial and ethnic minority adults: Fully remote, randomized pilot study. JMIR Form Res. 2022;6(12):e42191. doi:10.2196/42191.
  • Peng S, Othman AT, Yuan F, Liang J. The effectiveness of planning interventions for improving physical activity in the general population: A systematic review and meta-analysis of randomized controlled trials. Int J Environ Res Public Health. 2022;19(12):7337. doi:10.3390/ijerph19127337.
  • Preuhs K, Eekhout I, Andree R, van Keulen H, van Empelen P. Effective behavior change techniques for successful weight loss and weight loss maintenance among adults with overweight and obesity: A systematic review and meta-analysis. Obes Rev. 2026:e70195. doi:10.1111/obr.70195.
  • Riddell H, Sedikides C, Sivaramakrishnan H, et al. A meta-analytic review and conceptual model of the antecedents and outcomes of goal adjustment in response to striving difficulties. Nat Hum Behav. 2026;10(2):317-332. doi:10.1038/s41562-025-02312-4.
  • Singh B, Murphy A, Maher C, Smith AE. Time to form a habit: A systematic review and meta-analysis of health behaviour habit formation and its determinants. Healthcare (Basel). 2024;12(23):2488. doi:10.3390/healthcare12232488.
  • Van de Velde L, Gardner B, Van Dyck D, VÄ›trovský T, Compernolle S. Exploring habit strength, reward value, and context stability of sedentary activities in older adults: An ecological momentary assessment study. Appl Psychol Health Well Being. 2026;18(2):e70144. doi:10.1111/aphw.70144.
  • Vohra S, Shamseer L, Sampson M, et al.; CENT Group. CONSORT extension for reporting N-of-1 trials (CENT) 2015 Statement. BMJ. 2015;350:h1738. doi:10.1136/bmj.h1738.

 

Weight Maintenance, Flexibility & Long-Term Conditions

 

  • Aronne LJ, Sattar N, Horn DB, et al. Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity: The SURMOUNT-4 randomized clinical trial. JAMA. 2024;331(1):38-48. doi:10.1001/jama.2023.24945.
  • Budini B, Luo S, Tam M, et al. Trajectory of weight regain after cessation of GLP-1 receptor agonists: A systematic review and nonlinear meta-regression. EClinicalMedicine. 2026;93:103796. doi:10.1016/j.eclinm.2026.103796.
  • Pearl RL, Puhl RM. Weight bias internalization and health: A systematic review. Obes Rev. 2018;19(8):1141-1163. doi:10.1111/obr.12701.
  • Rubino D, Abrahamsson N, Davies M, et al. Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance in adults with overweight or obesity: The STEP 4 randomized clinical trial. JAMA. 2021;325(14):1414-1425. doi:10.1001/jama.2021.3224.
  • Thøgersen-Ntoumani C, Dodos LA, Stenling A, Ntoumanis N. Does self-compassion help to deal with dietary lapses among overweight and obese adults who pursue weight-loss goals? Br J Health Psychol. 2021;26(3):767-788. doi:10.1111/bjhp.12499.
  • West S, Scragg J, Aveyard P, et al. Weight regain after cessation of medication for weight management: Systematic review and meta-analysis. BMJ. 2026;392:e085304. doi:10.1136/bmj-2025-085304.
  • Westenhoefer J, Engel D, Holst C, et al. Cognitive and weight-related correlates of flexible and rigid restrained eating behaviour. Eat Behav. 2013;14(1):69-72. doi:10.1016/j.eatbeh.2012.10.015.
  • Wilding JPH, Batterham RL, Davies M, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension. Diabetes Obes Metab. 2022;24(8):1553-1564. doi:10.1111/dom.14725.