Medicine
Core Concepts in Nutrition
Quick fact
The human body requires at least 13 vitamins and 15 minerals to function properly, and most must come from food because the body cannot produce them.
Why this is interesting
You carefully count calories, but did you know that the type of calories you eat can affect your body differently? What truly makes food 'healthy' goes far beyond a single number.
Read the full explanation
Understanding Core Concepts in Nutrition
Think of nutrition as the fuel and raw materials for your body's engine. Macronutrients—carbohydrates, proteins, and fats—are needed in large amounts. Carbohydrates are your body's primary energy source, proteins build and repair tissues, and fats support cell growth and hormone production. Micronutrients (vitamins and minerals) are required in tiny amounts but are vital for processes like immune function, bone health, and energy production. Water is also crucial for nearly every bodily function. Energy balance—the relationship between calories consumed and calories burned—determines weight changes, but the quality of those calories affects overall health beyond weight.
A deeper explanation
The core of nutrition lies in how the body extracts and uses nutrients. Digestion breaks down food into absorbable molecules: carbohydrates into sugars, proteins into amino acids, and fats into fatty acids. These molecules enter the bloodstream and are transported to cells, where they are used for energy (via cellular respiration), built into new proteins, or stored for later use. Vitamins and minerals act as cofactors and antioxidants, enabling enzymes to catalyze reactions. For example, vitamin C is essential for collagen synthesis, and iron is critical for oxygen transport. Energy balance is regulated by hormones like insulin and leptin, which signal hunger and satiety. Understanding these mechanisms explains why a diet rich in whole foods—packed with fiber, vitamins, and healthy fats—supports long-term health, while processed foods can disrupt metabolic signals and lead to chronic disease.