Biology
Core Concepts in Nutrition
Quick fact
Your body uses over 40 different nutrients from food to function, yet no single food contains all of them—which is why variety matters.
Why this is interesting
You eat every day, but what is actually happening to the nutrients you consume? Why do some foods keep you full longer than others?
Read the full explanation
Understanding Core Concepts in Nutrition
Think of nutrition as the fuel and building materials your body needs to run. Macronutrients—carbohydrates, proteins, and fats—provide energy (calories) and structural components. Micronutrients—vitamins and minerals—are needed in smaller amounts but are vital for chemical reactions. The concept of energy balance (calories in vs. calories out) determines weight change. A balanced diet includes a mix of these nutrients in proportions that meet your body's needs, guided by dietary guidelines like the food pyramid or MyPlate.
A deeper explanation
After you eat, digestion breaks food down into absorbable molecules: carbs become glucose (energy), proteins become amino acids (tissue repair), fats become fatty acids (cell membranes and energy storage). Vitamins and minerals act as cofactors for enzymes, enabling metabolism to run smoothly. The body prioritizes immediate energy needs, then stores excess as glycogen or fat. Chronic imbalances—like too many calories or too few vitamins—lead to health issues like obesity or deficiency diseases. Understanding these core concepts allows you to evaluate diet quality by looking at nutrient density (nutrients per calorie) rather than just calorie count.