Nutrition Trivia

Everything you eat eventually gets broken down into a fairly short list of ingredients your body actually uses: carbohydrates, fats, proteins, vitamins, minerals, and water. Nutrition science is largely the study of how those pieces get used, stored, or missed when they're lacking. This quiz covers the fundamentals.

Macronutrients: Where the Calories Come From

Fat is the most calorie-dense macronutrient at roughly nine calories per gram, compared to about four calories per gram for both carbohydrates and protein. That doesn't make fat the enemy, though, since dietary fat is essential for absorbing certain vitamins and supporting cell function.

• Carbohydrates are the body's quickest source of usable energy.
• Protein supplies the amino acids needed to build and repair tissue.
• Excess glucose gets stored as glycogen in the liver and muscles for later use.

Vitamins and Minerals Doing Outsized Work

Small quantities of certain nutrients can prevent big problems. Vitamin C deficiency causes scurvy, a disease that plagued sailors for centuries before anyone understood why citrus fruit prevented it, while vitamin D deficiency can lead to rickets in children. Iron deficiency remains the most common nutritional cause of anemia worldwide, since without enough of it, red blood cells struggle to carry oxygen efficiently.