Weight Loss Fixes Hunger Hormones but Appetite Feelings Stay the Same

Moderate weight loss corrected leptin and ghrelin rhythms toward normal patterns, but subjective hunger and fullness feelings did not change.

Hernández Morante, Juan José et al.·Nutrients·2020·Preliminary EvidenceInterventional (diet study with controls)
RPEP-04851Interventional (diet study with controls)Preliminary Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Interventional (diet study with controls)
Evidence
Preliminary Evidence
Sample
N=33
Participants
20 obese adults + 13 normal-weight controls

What This Study Found

Weight loss produced the expected hormonal changes: leptin (the fullness hormone) decreased overall (P = 0.020 for area under curve and mean level). Ghrelin (the hunger hormone) increased. Both hormones' daily rhythms were modified to more closely resemble those of normal-weight individuals.

The amount of variability in leptin and ghrelin daily rhythms correlated with diet effectiveness (P < 0.001 for both). People whose hormone rhythms changed more also lost more weight.

The disconnect: despite these hormonal improvements, subjective appetite sensations (hunger, fullness, desire to eat) barely changed. Patients still felt approximately the same hunger after losing weight as before.

This confirms that in obesity, the hormonal signals (leptin and ghrelin) cannot properly reach or influence the brain centers that control conscious hunger and satiety. Weight loss partially restores the hormones but does not fix the broken communication.

Key Numbers

20 obese, 13 controls; 12 weeks; leptin decreased P=0.020; ghrelin increased; rhythm variability correlated with weight loss P<0.001; appetite unchanged

How They Did This

Interventional study with 20 obese subjects and 13 normal-weight controls. Obese participants underwent 12 weeks of calorie-restricted diet. Plasma leptin and ghrelin were measured at baseline and end of intervention with multiple time points to capture daily rhythms. Appetite was assessed using validated visual analog scales.

Why This Research Matters

This explains why dieting is so hard. Even when weight loss corrects hormone levels, the brain does not get the message. The hormones are screaming "you're not hungry" but the person still feels hungry. Understanding this hormone-brain disconnect is key to developing better obesity treatments.

The Bigger Picture

This explains a fundamental challenge in obesity treatment: even when hormones normalize, the brain may not register the change. The disconnect between hormonal signals and conscious appetite suggests that weight management requires addressing both biology and perception.

What This Study Doesn't Tell Us

Small sample (20 obese, 13 controls). Twelve weeks may not be long enough for appetite regulation to fully adapt. Appetite was measured by self-report, which is subjective. The study measured only leptin and ghrelin; other appetite-regulating hormones (GLP-1, PYY, CCK) were not assessed. No long-term follow-up to see if appetite eventually recalibrates.

Questions This Raises

  • ?How long after weight loss do appetite sensations eventually align with hormones?
  • ?Do GLP-1 drugs succeed because they bypass this hormone-perception disconnect?
  • ?Would longer-duration studies show eventual appetite normalization?

Trust & Context

Key Stat:
Hormones changed, appetite didn't leptin and ghrelin rhythms normalized after weight loss, but hunger and fullness feelings remained unchanged
Evidence Grade:
Preliminary evidence from a small interventional study. Clear hormonal changes documented, but the appetite disconnect needs confirmation in larger, longer studies.
Study Age:
Published in 2020. The hormone-appetite disconnect is now better understood and informs GLP-1 drug development.
Original Title:
Moderate Weight Loss Modifies Leptin and Ghrelin Synthesis Rhythms but Not the Subjective Sensations of Appetite in Obesity Patients.
Published In:
Nutrients, 12(4) (2020)
Database ID:
RPEP-04851

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

If my hormones improve with weight loss, why am I still hungry?

Your hunger hormones may be sending the right signals, but your brain's appetite perception does not immediately recalibrate. This disconnect is a biological reality, not a willpower failure.

Does this mean dieting is pointless?

No — the hormonal improvements are real and beneficial. But this study explains why dieting alone may need to be supplemented with strategies that address appetite perception, including medications or behavioral approaches.

Read More on RethinkPeptides

Cite This Study

RPEP-04851·https://rethinkpeptides.com/research/RPEP-04851

APA

Hernández Morante, Juan José; Díaz Soler, Inmaculada; Muñoz, Joaquín S Galindo; Sánchez, Horacio Pérez; Barberá Ortega, Mª Del Carmen; Martínez, Carlos Manuel; Morillas Ruiz, Juana Mª. (2020). Moderate Weight Loss Modifies Leptin and Ghrelin Synthesis Rhythms but Not the Subjective Sensations of Appetite in Obesity Patients.. Nutrients, 12(4). https://doi.org/10.3390/nu12040916

MLA

Hernández Morante, Juan José, et al. "Moderate Weight Loss Modifies Leptin and Ghrelin Synthesis Rhythms but Not the Subjective Sensations of Appetite in Obesity Patients.." Nutrients, 2020. https://doi.org/10.3390/nu12040916

RethinkPeptides

RethinkPeptides Research Database. "Moderate Weight Loss Modifies Leptin and Ghrelin Synthesis R..." RPEP-04851. Retrieved from https://rethinkpeptides.com/research/hernandez-2020-moderate-weight-loss-modifies

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.