D5 - Beyond Calories Flashcards
What is the energy balance equation?
The energy balance equation is defined as calories in divided by calories out.
Why did our brains evolve to prioritize certain foods?
Over time, our brains evolved to prioritize foods that are readily accessible, palatable, and provide high amounts of micro and macronutrients for survival.
What is the mesolimbic pathway, and what does it consist of?
The mesolimbic pathway, also known as the reward pathway, consists of the nucleus accumbens (NA) and ventral tegmental area (VTA). It is involved in prioritizing rewarding experiences.
What role does dopamine play in the reward system?
Dopamine helps determine whether an activity is rewarding or not.
What hormones are involved in hunger and satiety, and where are they produced?
Ghrelin, produced in the stomach, drives hunger, while leptin, produced in adipose tissue, suppresses appetite. These hormones interact with the hypothalamus.
How did the availability and ease of access to food influence the brain’s reward system?
Foods that were readily available, palatable, and calorically dense were ranked higher in the reward system, influencing the body’s caloric satisfaction.
How did our brains adapt to the ranking system of food preferences?
Over time, our brains adapted to prioritize high-ranking foods with sweet and savory tastes, such as those high in sugar and fat, to generate a dopamine response.
Why might our ancestors have craved foods high in fiber and protein?
Fiber and protein have effects on satiety, leading to some quantity control. This, in turn, increases leptin, signaling the hypothalamus that sufficient energy is present in the body.
What effect do rewarding foods, particularly sweet and savory ones, have on people’s eating habits?
Rewarding foods can lead people to eat more, contributing to overconsumption.
What characteristics make foods highly addictive?
Highly addictive foods are readily available, addictive, and often sugar-laden, containing sucrose or high-fructose corn syrup.
What happens when glucose is ingested, and how does the pancreas respond?
When glucose is ingested, the pancreas produces insulin. Approximately 20% goes to the liver for glycogen conversion, while the rest enters the bloodstream.
How does the metabolism of fructose differ when it comes from natural sources versus highly processed foods?
When fructose comes from natural sources with fiber, it slows absorption. However, in highly processed foods lacking fiber, fructose enters the liver rapidly, leading to fat accumulation.
