Calories aren't the whole story: hormones decide where fat goes
Shawn Stevenson, female fitness experts and research on fasting and hunger all emphasize the same thing: insulin and other hormones govern whether fat is stored or released, and meal timing and food quality shape those signals. This shifts fat loss from pure calorie math toward managing hormonal context.
Do these experts say calories don't matter? Show answer
No. All of them say calories still count, but that hormones and food quality shape how much people eat and what the body does with the energy.
How do insulin and glucagon steer fat, according to Shawn Stevenson? Show answer
Insulin stores energy and blocks fat burning. Glucagon releases stored fat but cannot do its job while insulin is elevated.
What is the thermic effect of food? Show answer
The share of calories burned in digestion: 20 to 30% for protein, 5 to 10% for carbohydrates and 0 to 3% for fat.
What five factors does Stevenson say sit behind a calorie? Show answer
The type of food, how it is prepared, the energy cost of digesting it, digestive efficiency and the makeup of the gut microbiome.
Where does lost fat go, according to Stevenson? Show answer
84% leaves through the lungs as carbon dioxide and 16% through sweat and urine.
How long does it take to reach a fasted state after eating, according to Andrew Huberman? Show answer
Roughly five to six hours after the last bite, when glucose and insulin fall and glucagon rises.
What did Satchin Panda's 2012 mouse study find? Show answer
Mice eating the same high-fat calories within an eight-hour window maintained or lost weight, while mice eating around the clock became obese and sick.
Why did the eight-hour window work in the human study Huberman cites? Show answer
It produced a mild calorie restriction and weight loss without calorie counting, because people ate less.
What does Dr. Stacy Sims say happens when a woman trains without eating? Show answer
Morning cortisol stays high, the body breaks down muscle and bone for fuel, and it gets a signal to keep body fat.
What does Sims advise women to eat in the morning? Show answer
A little before any morning exercise, such as half a banana, and about 30 grams of protein early in the day.
How do processed foods cause overeating, according to Huberman? Show answer
Emulsifiers strip the gut's lining so fullness signals don't fire. In one study people on a processed diet ate much more and gained weight.
Where do Sims and Huberman differ on fasted exercise? Show answer
Sims says women's bodies don't respond well to it, while Huberman says most exercise can be done fasted. Sims is speaking specifically about women.