Tag: Knowledge recall

The same food can spike blood glucose dramatically in one person while barely affecting another. Research by Zeevi showed variation between people is larger than variation from food to food. Factors include genetics, insulin resistance, body composition, gut microbiome, sleep, stress, and meal timing. Glycemic index tables are averages — useful but not necessarily accurate for you. This companion covers factors influencing response, the landmark research, and why self-observation through glucose monitoring matters. (3 min read)

Fat adaptation means becoming efficient at burning fat rather than relying on glucose. Research by Volek shows it takes weeks to months: increased mitochondrial density, upregulated enzymes, improved ketone production. Once adapted, you experience stable energy, reduced hunger, easier fasting. Two paths: extended carbohydrate restriction or regular fasting — most combine both. This companion covers the two fuel systems, physiological changes, timeline, how to get there, and signs of adaptation. (3 min read)

In the fed state, insulin rises, signaling storage: glucose into glycogen, excess into fat. In the fasted state, insulin drops, signaling release: first glycogen, then fat. Research by Anton on the metabolic switch shows constant eating keeps you in storage mode. Fat burning requires time without incoming fuel — typically 8-12 hours after your last meal. This companion covers what happens in each state, why it matters, and practical implications including meal spacing and overnight fasting. (3 min read)

Basal metabolic rate is determined primarily by body size, composition, age, and genetics. Research by Levine on NEAT shows total daily activity is more variable than BMR. Each pound of muscle burns only about 6 calories daily at rest — meaningful but not transformative. No supplement or quick fix meaningfully boosts metabolism. Focus on sustainable habits, muscle maintenance, and total activity. This companion covers what determines BMR, what you can change, what you can’t, and practical implications. (3 min read)

Autophagy is cellular self-cleaning — cells break down and recycle damaged components. Research shows it increases significantly during fasting, becoming notable around 24-48 hours in animal models. Potential benefits include improved cellular health, reduced inflammation, and protection against age-related disease. Eating suppresses autophagy via mTOR activation. This companion covers what autophagy is, when it occurs, why it might be beneficial, caveats about human research, and practical applications. (3 min read)

Ghrelin follows your established eating patterns, rising in anticipation of meals and falling whether or not you actually eat. Research by Cummings shows ghrelin operates as an anticipatory signal, not a continuous hunger alarm. That 12pm hunger isn’t biological necessity — it’s learned timing. Change the pattern, and ghrelin adapts over days to weeks. This companion covers ghrelin basics, the anticipatory pattern, adaptation to new schedules, and practical implications for fasting. (3 min read)

The glycemic index measures how quickly food raises blood sugar, but it’s not the whole story. Research by Zeevi found enormous individual variation in responses to identical foods. GI doesn’t account for portion size, ignores insulin response, varies with preparation and combinations. Watermelon has high GI but low carb per serving; ice cream has moderate GI but isn’t health food. This companion covers how GI works, its four major limitations, and how to use it wisely as one tool among many. (3 min read)

Several hormones signal fullness: CCK responds to fat and protein, PYY rises as food moves through the gut, GLP-1 slows gastric emptying. Research by Batterham shows protein triggers the strongest PYY response. These hormones respond to actual nutrients—protein, fiber, fat—not liquid calories or ultra-processed foods that bypass the satiety system. This companion covers CCK, PYY, GLP-1, and leptin, what triggers them, and what doesn’t activate your body’s fullness signaling. (3 min read)

Insulin responds to more than just carbohydrates. Research by Holt on the insulin index found some foods that barely raise blood sugar still trigger significant insulin release. Whey protein is highly insulinogenic. Dairy products consistently score higher than their carbohydrate content predicts. Some artificial sweeteners may affect insulin through taste receptors. This companion covers going beyond the glycemic index, protein and insulin, the dairy paradox, and practical implications. (3 min read)

When blood sugar spikes and crashes, so does everything else—mood, energy, decision-making. Research by Ludwig found high-glycemic meals cause blood sugar to crash four hours later, with increased hunger and craving activation. The brain’s prefrontal cortex, responsible for impulse control, is especially vulnerable. “Hangry” has research support. This companion covers the glucose- brain connection, the spike-crash cycle, mood and irritability effects, and practical ways to stabilize blood sugar. (3 min read)