Why High Insulin Prevents Your Body from Burning Stored Fat

The Fat Trap

You are carrying stored fat. That fat represents hundreds of thousands of calories of potential energy. Yet despite that reserve, many people feel tired, hungry, and unable to lose weight. The reason, according to species-appropriate diet practitioners, is one hormone: insulin. When insulin is elevated, the body's fat stores are locked away — and it does not matter how much body fat you have.

What Insulin Actually Does

Insulin is released by the pancreas when blood sugar rises — primarily in response to carbohydrate intake. Its job is to move glucose out of the bloodstream and into cells, where it can be burned for energy or converted into fat for storage. This is critical: glucose circulating in the blood at high levels is directly toxic to tissues, so the body uses insulin as an emergency signal to get it out of the blood as quickly as possible.

Dr Anthony Chaffee explains the storage imperative this way:

"Your body has to elevate insulin and get all of these other processes out of balance just to protect you from that glycation. That fat came from eating excessive amounts of carbohydrates... and you had to elevate your insulin to store that and get it the hell out of your bloodstream quickly before it killed you."
— Dr Anthony Chaffee MD

The Lock on the Fat Cell

Here is the mechanism that explains why fat loss stalls on a high-carbohydrate diet. Insulin does not just promote fat storage — it actively blocks fat release. Think of insulin as a switch that forces energy into cells and simultaneously prevents energy from coming out.

"You can think of it as forcing energy into cells. It doesn't allow it to come out of cells. So when your insulin level is up, you can't start using your fat as energy... if your insulin gets high enough, you cannot burn fat."
— Dr Anthony Chaffee MD

The technical term for fat breakdown is lipolysis — the process by which fat cells release fatty acids into the bloodstream so they can be burned for fuel. Insulin directly suppresses lipolysis. As long as insulin is elevated, the body is in storage mode, not burning mode, regardless of how much fat is sitting in the adipose tissue.

"Carbohydrates will raise insulin. Insulin blocks lipolysis. So now you can't generate more energy and your blood sugar will start dropping to a point that you feel lethargic. You can't make ketones and you feel pretty crummy and you go and chase those carbs again."
— Dr Anthony Chaffee MD

The Vicious Insulin Cycle

This is the trap that Chaffee and other species-appropriate diet practitioners describe seeing in patients who cannot lose weight despite eating less. Carbohydrates raise insulin. Elevated insulin blocks lipolysis. With fat stores locked, the only available fuel is whatever glucose is currently circulating — which runs out quickly. Blood sugar drops, hunger surges, and the person reaches for more carbohydrates. The cycle repeats.

"Your insulin is always up, your glucagon is always down — so you're storing. But you're never burning. And here you go. You have to eat every two hours. You're like in prison."
— Dr Anthony Chaffee MD

The person eating a carbohydrate-heavy diet is in a state of metabolic imprisonment: they have enormous energy reserves locked in their fat tissue but cannot access any of it. They eat to survive on short-term glucose, while their body fat accumulates untouched.

Glucagon: The Anti-Insulin

The hormone that does the opposite of insulin — that unlocks fat stores and drives lipolysis — is glucagon. Glucagon is released when blood sugar drops and insulin is low. It signals fat cells to release their stored fatty acids and tells the liver to generate new glucose through gluconeogenesis.

"The main driver of lipolysis is glucagon. Glucagon is the anti-insulin — it does a lot of the opposite things to insulin, and this will cause you to burn fat and to elevate your blood sugar through gluconeogenesis. When we have patients in the hospital who are in a coma because of hypoglycemia, we don't give them cortisol, we don't give them adrenaline. We give them an injection of glucagon — because that is what drives lipolysis and gluconeogenesis. This is in biochemistry textbooks."
— Dr Anthony Chaffee MD

Insulin and glucagon are opposing hormones. When insulin is high, glucagon is suppressed. When insulin is low — as it is on a species-appropriate or ketogenic diet — glucagon rises and the fat-burning signal turns on.

Insulin's Wider Effects

Locking fat in storage is not insulin's only effect at chronically elevated levels. Chaffee notes that high insulin disrupts over a hundred distinct physiological mechanisms:

"Besides just locking in your fat cells, insulin affects over a hundred different mechanisms in your body, your physiology, and your metabolism. So it's really important to keep that at normal levels. And when you elevate it with carbohydrates, then all of these other mechanisms are out of balance. This is actually the stem of a lot of chronic diseases."
— Dr Anthony Chaffee MD

Other effects of chronically elevated insulin documented in the transcripts include:

• Suppresses autophagy — the body's cellular repair and recycling process
• Blocks ketone production — preventing the brain from switching to fat-derived fuel
• Blocks leptin signalling — the satiety hormone, so the brain cannot register fullness
• Disrupts sex hormones — high insulin is the leading driver of PCOS and suppresses growth hormone in both sexes
• Forces ectopic fat deposition — fat deposited in muscles and around organs (visceral fat), the same mechanism used to marble wagyu beef
• Promotes insulin resistance — cells downregulate insulin receptors in response to chronic excess, requiring even higher insulin to achieve the same effect

Why species-appropriate diet Breaks the Cycle

A zero-carbohydrate diet removes the primary trigger for insulin spikes. Protein raises insulin moderately and transiently; dietary fat raises it barely at all. With no carbohydrates, insulin stays low, glucagon rises, and the fat-burning pathway stays open. The body gains continuous access to its stored fat — often for the first time in years.

Chaffee's clinical observation is that patients on a species-appropriate diet stop needing to eat every two hours because their body can finally draw on its stored fat between meals. The locked-storage problem dissolves when the key — the carbohydrate-driven insulin spike — is removed.