Move through the study
Body weight
Starting weight
Tap any hormone name to read what it does. Bars show the direction each hormone moved in the study, not a prediction of your own levels. Each hormone starts from its own baseline, so bar heights compare a hormone with itself rather than with the others.
So what is food noise?
Researchers gave the term a formal definition in 2025: persistent thoughts about food that the person experiences as unwanted or distressing, and that may cause social, mental or physical harm. What separates it from normally thinking about lunch is the intensity and the intrusiveness. The researchers compare it to rumination, meaning thoughts that keep circling back whether you want them to or not.
It is a way of thinking, not a hormone level, and it is measured with a questionnaire rather than a blood test. That matters for how this page works: nothing here calculates how much food noise you have. What the hormone panel above shows is the leading explanation for why the volume goes up, which is a different and more honest claim.
Why it gets louder when you lose weight
The hunger signal goes up
Ghrelin is the only hormone in the panel whose job is to tell you to eat. After weight loss it rose, and a year later it was still above where it started. Your appetite is not louder because you have lost discipline. A hormone that says eat is being produced in larger amounts.
The fullness signals go down
Leptin, peptide YY, cholecystokinin, amylin and insulin all fell. These are the signals that end a meal and tell the brain there is enough energy stored. Fewer of them means meals satisfy less, and the brain reads the body as running low.
Hunger itself was measured, and it rose
The study did not only measure blood. It asked people how hungry they felt. Subjective appetite went up significantly after the weight loss, and was still elevated a year later. The felt experience matched the biology.
It did not wear off
This is the part that surprises people. A full year after the diet ended, with some weight regained, leptin, peptide YY, cholecystokinin, insulin, ghrelin, GIP and pancreatic polypeptide were all still different from baseline. The pressure to eat did not fade with time or habit.
Your body also burns less
Alongside the hormones, energy expenditure falls after weight loss. Rosenbaum and Leibel describe a coordinated set of metabolic, neuroendocrine and autonomic responses that defend the weight the body has lost, and note it happens in lean and heavier people alike.
Two results worth knowing
GIP went up after weight loss rather than down, and the body's own GLP-1 did not change significantly at all. That is worth saying plainly, because the medications are GLP-1 and GIP imitators. The drugs work on those pathways; that does not mean your own levels of them drop when you lose weight.
Your body defends a weight
The idea that the body works to hold body fat near a particular level is called set point theory. Leptin is the central messenger in it. Fat tissue makes leptin, leptin reports to the hypothalamus in the brain, and the brain adjusts hunger and energy use to keep stores where it expects them. Rosenbaum and Leibel describe body energy stores as actively defended by interlocking systems rather than passively drifting.
Set point is a model rather than a settled fact, and researchers debate how fixed that level really is and what can move it. What is not in dispute is the defending itself: the hormone and energy-expenditure changes above have been measured repeatedly.
In obesity, that system does not read the signal properly. Leptin levels are high, because leptin comes from fat tissue and there is more of it, yet the brain responds as though there were less. This is called leptin resistance, and it is characterised by reduced satiety and increased body mass. It is also why giving people extra leptin does not generally treat obesity.
So the honest version of "a regulated versus unregulated system" is this: the regulation is still running in obesity. It is defending a higher level, and the fullness signal it depends on is not being heard.
Obesity is biological. It is not your fault
Every measurement on this page points the same way. When weight comes off, the hunger hormone rises, the fullness hormones fall, hunger increases, energy expenditure drops, and a year later those changes are still there. None of that is a choice, and none of it is a personality trait.
The genetics point the same way too. Reviewing decades of gene-discovery work, Loos and Yeo report that both common obesity and the rare severe forms share genetic and biological underpinnings, and that those findings point to a central role for the brain in the control of body weight. In 2025 a Lancet commission set out formal diagnostic criteria for obesity as a clinical condition rather than a lifestyle outcome.
Food noise is what that biology sounds like from the inside. Hearing it constantly is not weakness, and needing help to quiet it is not a shortcut.
Where the medications come in
GLP-1 medications imitate the gut hormone of the same name, and tirzepatide acts on the GIP receptor as well. They add a fullness signal from outside rather than restoring the ones the body reduced. Many people describe the food noise getting quieter on them, and a 2026 study of people starting semaglutide set out to measure that change directly.
The research here is young. Food noise only received a formal definition and a questionnaire in 2025, and a 2026 commentary in Appetite argues that more conceptual and measurement work is needed before it is used clinically, including care not to turn an ordinary experience into a diagnosis. What each medication was tested on is in the medication guide, and the protein calculator covers eating enough while appetite is suppressed.
This is education, not medical advice
This page explains published research. It does not diagnose anything and it does not measure your own hormones or your own food noise. Persistent, distressing thoughts about food can also be a feature of an eating disorder, which is worth raising with a clinician rather than managing alone.
Sources
- Sumithran P, Prendergast LA, Delbridge E, et al. Long-term persistence of hormonal adaptations to weight loss. New England Journal of Medicine. 2011;365(17):1597–1604. doi:10.1056/NEJMoa1105816. Fifty adults, a 10-week very-low-energy diet, measured at baseline, at 10 weeks and at 62 weeks. Source of every hormone direction on this page: reductions in leptin, peptide YY, cholecystokinin, insulin and amylin, increases in ghrelin, GIP and pancreatic polypeptide, an increase in subjective appetite, and the finding that most were still altered a year later. GLP-1 was measured and was not among the significant changes.
- Dhurandhar EJ, Maki KC, Dhurandhar NV, Kyle TK. Food noise: definition, measurement, and future research directions. Nutrition & Diabetes. 2025;15:30. doi:10.1038/s41387-025-00382-x. Source of the formal definition, of the RAID-FN Inventory questionnaire, and of the statement that the physiological underpinnings of food noise remain to be researched.
- Brewis A, Hayashi D, Gualano B, Precinotto ML. Food noise: conceptual, methodological, and ethical considerations. Appetite. 2026;226:108700. doi:10.1016/j.appet.2026.108700. Source of the caution that evidence on mechanisms and measurement is still limited, and of the concern about reclassifying common experiences as pathology.
- Rosenbaum M, Leibel RL. Adaptive thermogenesis in humans. International Journal of Obesity. 2010;34(Suppl 1):S47–S55. doi:10.1038/ijo.2010.184. Source for energy stores being actively defended by coordinated metabolic, neuroendocrine and autonomic responses, in lean and heavier people alike.
- Obradovic M, Sudar-Milovanovic E, Soskic S, et al. Leptin and obesity: role and clinical implication. Frontiers in Endocrinology. 2021;12:585887. doi:10.3389/fendo.2021.585887. Source for leptin coming from fat tissue, acting on the hypothalamus in a negative feedback loop, and for leptin resistance being characterised by reduced satiety and increased body mass.
- Loos RJF, Yeo GSH. The genetics of obesity: from discovery to biology. Nature Reviews Genetics. 2022;23(2):120–133. doi:10.1038/s41576-021-00414-z. Source for common and rare obesity sharing genetic and biological underpinnings, and for those findings pointing to a key role for the brain in the control of body weight.
- Rubino F, Cummings DE, Eckel RH, et al. Definition and diagnostic criteria of clinical obesity. The Lancet Diabetes & Endocrinology. 2025;13(3):221–262. doi:10.1016/S2213-8587(24)00316-4. The commission that set out formal diagnostic criteria for obesity as a clinical condition.
- Arnaut T, Duncan S, Faurby M, Hahn-Pedersen JH, et al. Retrospective assessment of food noise changes after initiation of injectable semaglutide for weight management in the USA: the INFORM study. Advances in Therapy. 2026;43:3649–3659. doi:10.1007/s12325-026-03636-x. A 2026 study measuring reported food noise change after starting semaglutide.