"Anything Meds Can Do, You Can Do Better" Part 7 of 12 - Brain Insulin Resistance

Brain Insulin Resistance: Why You’re Hungry, Foggy, and Tired — And How to Take Back Your Brain

In this Diabetes Podcast episode, Richie and Amber break down Brain Insulin Resistance in simple, clear language. If you feel hungry all the time, crave carbs, feel tired even after sleep, or struggle to stick with healthy habits, this one’s for you. We explain what insulin does in a healthy brain, what goes wrong with Brain Insulin Resistance, how it can change your memory and mood, and practical steps you can start today.

Episode Summary

• Your brain does not need insulin to get glucose (sugar) into brain cells. But your brain does need insulin for signaling. That signaling helps with hunger, fullness, mood, motivation, memory, and focus.
• When Brain Insulin Resistance shows up, the brain “can’t hear” insulin. You may feel constant hunger, strong cravings, brain fog, low motivation, and trouble sticking to healthy habits.
• Over time, Brain Insulin Resistance can raise inflammation and stress in the brain. This can affect white matter, the hippocampus (memory), and even raise amyloid/tau changes seen in Alzheimer’s. That’s why diabetes raises risk for cognitive decline.
• GLP-1 medicines can help hunger and cravings. But they often plateau after about a year if lifestyle doesn’t change. The real power is in daily habits: movement, sleep, stress care, and a plant-forward, high-fiber, anti-inflammatory diet.
• Good news: when you lower insulin resistance in your whole body, you also help your brain. This is changeable. You can protect your energy, memory, and satiety.

What You’ll Learn

• What insulin does in a healthy brain
• Why you can feel hungry even after eating
• How Brain Insulin Resistance drives cravings, brain fog, and low motivation
• How it can change brain structure over time
• When meds help (GLP-1s) and when lifestyle matters most
• Simple steps to calm cravings, boost focus, and feel full

Key Takeaways

• Brain Insulin Resistance = the brain stops responding to insulin signals.
• Symptoms: constant hunger, carb cravings, brain fog, low motivation, trouble sticking to habits.
• Causes include: high insulin/high blood sugar, inflammation, high saturated fat and ultra-processed foods, poor sleep, chronic stress, sedentary time.
• Exercise is special: muscle contractions can pull glucose into muscle even without insulin (GLUT4 pathway). Moving your body helps your brain.
• The brain uses about 20% of your resting energy. It prefers fast fuel (glucose).
• Over time, Brain Insulin Resistance can raise oxidative stress and brain inflammation (microglia). This links to cortical thinning, reduced hippocampus volume, white matter changes, and more amyloid/tau — patterns also seen in Alzheimer’s.
• GLP-1 medicines can lower hunger and food chatter. But results often fade if habits don’t change.
• Daily basics work: move often, sleep well, manage stress, eat more plants and fiber, and cut ultra-processed foods.

Simple Science (kept simple)

• Brain fuel: Most brain cells use GLUT1 and GLUT3 “doors” to bring in glucose. These do not need insulin.
• Muscle fuel: Muscles use GLUT4 “doors.” GLUT4 opens with insulin — and also opens with exercise. So moving your body helps use sugar even when insulin is low or not working well.
• What insulin does in the brain: It helps hunger and fullness signals (ghrelin, leptin), supports dopamine and serotonin (motivation and mood), calms inflammation, and helps memory and focus.
• Brain Insulin Resistance: The insulin signal is there, but the brain can’t “hear” it well. You feel unsatisfied after eating. Cravings rise. Focus drops. Motivation drops. Over time, inflammation and oxidative stress go up.

Signs You Might Have Brain Insulin Resistance

• Always hungry, even after meals
• Strong carb and sugar cravings
• Brain fog, poor focus, forgetfulness
• Low motivation; hard to start or stick with habits
• Feeling tired, but not refreshed
• Feeling “not yourself” mentally

If this sounds like you, you’re not “weak.” Your brain signals may be off. You can change them.

What Can Drive Brain Insulin Resistance

• Chronically high insulin and blood sugar
• High saturated fat and ultra-processed foods
• High-fructose corn syrup and sugary drinks
• Poor sleep; late-night eating
• Chronic stress
• Sedentary time (not moving enough)
• Systemic inflammation

How It Can Change the Brain

• More oxidative stress (free radical damage)
• Microglia (brain immune cells) stay “on,” causing low-grade inflammation
• White matter connections get weaker
• Hippocampus (memory center) shrinks
• Cortical thinning (especially frontal and t