Macronutrients are carbohydrates, proteins, fats, fiber, water. They are needed in large amounts. Micronutrients are vitamins, minerals, enzymes, phytochemicals. They are needed in small amounts.
Carbohydrates provide 4 calories of energy per gram. Simple carbohydrates release energy quickly. Complex carbohydrates release energy slowly.
Proteins provide 4 calories of energy per gram. Proteins are made of amino acids. Humans need 8 different types of essential amino acids.
Fats provide 9 calories of energy per gram. Fats are unsaturated, saturated, or cholesterol. At room temperature, unsaturated fats are liquid, saturated fats are solid, cholesterol is waxy.
Choose a staple grain for your long-term diet. The most common options are oats, rice, and wheat products.
Oats cooks fast (1-5 min in pot with hot water), contains more protein and iron. Get "quick oats" (rated for 1 min cook time) for a balance of cooking speed and tasteful texture.
Rice cooks and stores conveniently (10-30 min in rice cooker), tastes neutral for more recipe compatibility. Get both types of rice (white/brown) for a balance of neutral taste and potential nutrition.
Wheat products (ex. bread, cereal, pasta) are ready-to-eat with longer shelf-life and a more palatable standalone taste. Get bread with good texture and added seeds/grains for a balance of personal taste and extra nutrition.