Why Do We Get Hungry? 🍔🤔
👄 Oral Factors
- Taste & Smell 👅👃: Influence how much we eat! Yummy = more! 😋
- Chewing & Swallowing 🧠: Sends signals to brain! 📡
- Not Enough! ❌: Oral factors alone don't explain hunger! 🤔
💪 Gastric Factors: Stomach Signals
🎈 Cannon & Washburn Study (Classic!)
- Balloon in Stomach 🎈😅: Measured stomach contractions! 📈
- Contractions = Hunger! 😤: Empty stomach contracts → Feel hungry! 🍔
- Stretch Receptors 📍: Full stomach stretches → Stop eating! 🛑
🧪 Gut Peptides
- CCK (Cholecystokinin) 💊: Released when food in small intestine! 🍽️
- Satiety Signal 🛑: Tells brain "Stop eating!" 🧠❌
- Short-term Control ⏱️: Works meal-to-meal! 🍔
🧪 Metabolic Factors: Blood Signals
🍬 Glucostatic Theory (Mayer)
- Blood Glucose Monitor 📉: Brain watches blood sugar levels! 🧠👀
- Low Glucose = Hungry! 📉😤: Brain says "Need food!" 🍔
- High Glucose = Full! 📈😊: Brain says "Had enough!" 🛑
- Hypothalamus 🧠: Main glucose detector! 🎯
⚖️ Set Point Mechanisms
- Glucose Set Point 🎯: Body tries to maintain stable blood sugar! ⚖️
- Lipid Set Point 🍖: Body tries to maintain fat stores! 📏
- Feedback Systems 🔄: Deviations trigger corrective eating! 🍽️
🧠 Brain Control Centers
- Lateral Hypothalamus (LH) 🍔: "Feeding center" - Stimulate = Eat! 📈
- Ventromedial Hypothalamus (VMH) 🛑: "Satiety center" - Stimulate = Stop eating! ❌
- Balance is Key! ⚖️: LH vs VMH = Eating control! 🎯
🔑 Key Takeaways
- Multiple factors control hunger! 🍔🧠💪
- Oral factors = Not enough alone! 👄❌
- Stomach contractions signal hunger! 🎈😤
- CCK tells brain to stop! 💊🛑
- Blood glucose is KEY signal! 🍬📉
- Set points maintain stability! ⚖️🎯
- Hypothalamus is control center! 🧠🎮
- Complex system with redundancy! 🔄✅