People who are already overweight might eat less because their body doesn’t feel hungry — so it’s not that eating less makes you fat, it’s that being fat makes you eat less.
Scientific Claim
Central adiposity and metabolic dysregulation (e.g., leptin resistance) can reduce appetite and lead to decreased meal frequency, creating reverse causation in observational studies.
Original Statement
“Have you ever thought that in a study like this, it's a snapshot in time where they just looked at a bunch of epidemiological data and they said, 'Okay, well, men that eat one or two meals per day are more fat.' Have you ever thought that maybe the fat people were trying to lose weight so were only eating one or two meals per day and that's why they were eating one or two meals per day because they were already overweight or because they had so much leptin resistance that maybe they just didn't have that much of an appetite and things were really cattywampus because they're totally metabolically deranged.”
Context Details
Domain
nutrition
Population
human
Subject
central adiposity and metabolic dysregulation
Action
reduce appetite and decrease meal frequency
Target
eating behavior
Intervention Details
Evidence from Studies
Supporting (2)
When the body can't respond to the 'full' signal from leptin, it still eats less — which means obesity might cause reduced eating, not the other way around.
Technical explanation
This study directly shows that leptin dysfunction leads to reduced food intake and body weight via hypothalamic appetite regulation, demonstrating that leptin resistance can suppress appetite — a core component of the assertion's claim about reverse causation in observational studies.
When rats are leptin-resistant, they eat less; fixing that resistance makes them eat more — proving that fat-related hormone problems can cause less eating.
Technical explanation
This paper directly links leptin resistance to reduced appetite in obese rats, showing that correcting leptin resistance improves satiety — supporting the idea that metabolic dysregulation can cause decreased meal frequency, not just result from it.
Contradicting (4)
This study found that people who ate fewer meals per day tended to lose weight, but it didn’t look at whether being overweight or having metabolic problems made them eat less — so it doesn’t support the idea that body fat causes people to eat less.
Early Time-Restricted Feeding Reduces Appetite and Increases Fat Oxidation but Does Not Affect Energy Expenditure in Humans
This study found that eating earlier in the day makes people feel less hungry, but it didn’t look at whether being overweight or having hormone problems causes people to eat less — so it doesn’t support the claim that fat and hormone issues lead to reduced appetite.
These rats get fat even though they don’t eat more — so fat gain doesn’t always come from eating more, and doesn’t always make you eat less — breaking the link the assertion assumes.
Technical explanation
This paper directly contradicts the assertion by showing that rats gain fat without eating more — proving that metabolic dysregulation can cause obesity independently of appetite changes, undermining the claim that reduced meal frequency is a consequence of leptin resistance.
When hamsters lose fat, they don’t get the health benefits from a hormone that normally helps metabolism — meaning fat isn’t just a problem; it’s needed for the body to work right, so it can’t be causing less eating.
Technical explanation
This study shows that reducing fat mass (adiposity) leads to reduced metabolic benefits of FGF21 — implying that fat tissue is necessary for metabolic signaling, contradicting the idea that adiposity causes reduced appetite via leptin resistance.