Calorie restriction alone is unsustainable because high-carb meals spike insulin, which sequesters energy from the blood into storage cells. The brain, which lacks storage capacity, perceives this drop in available energy as a crisis and triggers intense, overriding hunger, even if body fat is abundant.
The cultural shift from three to six meals a day was a reaction to 1970s dietary advice. Low-fat, high-carb foods cause blood sugar crashes and frequent hunger, which led to the institutionalization of snacking to manage these new hunger pangs.
Reducing calorie intake triggers a corresponding drop in your basal metabolic rate. Your body simply starts burning fewer calories to match what you're eating, which stalls weight loss and explains why "just eat less" is flawed advice.
A practical strategy for managing insulin involves eliminating carbs from breakfast and lunch, focusing on protein and fat. Make lunch the day's largest meal to curb evening cravings. This structure allows for dietary flexibility at dinner, making the plan socially sustainable long-term.
Many clinicians mistakenly believe insulin's main role is blood glucose control. In reality, it's a master hormone signaling every cell—from brain to bone—to store energy. This function is so powerful it can slow the body's overall metabolic rate to prioritize energy storage.
Unlike simple calorie restriction, intermittent fasting lowers insulin levels. This hormonal signal allows your body to access and burn its fat stores to make up for a caloric deficit, preventing the metabolic slowdown that typically sabotages diets.
When insulin is low, the body becomes so opposed to fat storage that it produces excess ketones. These ketones, which have caloric value, are then expelled through breath and urine. This process represents an effortless expenditure of calories that would otherwise have to be stored or burned through exercise.
Eating high-carb foods frequently, even in a calorie deficit, keeps insulin high. This prevents your body from accessing stored fat for energy, forcing it to lower its metabolic rate. After the diet, this suppressed metabolism causes rapid weight regain.
The crash following a glucose spike activates the brain's craving center. This is a physiological command, not a lack of willpower. Stabilizing glucose levels eliminates the biological trigger for intense cravings, making them naturally disappear.
A typical sweet breakfast (cereal, juice, smoothie) creates a massive morning glucose spike, triggering a day-long cycle of cravings and fatigue. Switching to a savory breakfast built around protein stabilizes glucose levels from the start, providing steady energy and eliminating cravings.
Ketones are a more efficient energy source than glucose, producing less metabolic “trash” (oxidative stress). Crucially, they can penetrate the blood-brain barrier and fuel brain cells even when they've become resistant to insulin, directly combating cognitive decline and brain fog.