There isn’t a single universal answer, because “classes of food” can be defined differently depending on the framework or country, but here are the most common ways it’s taught today: Direct answer

• Most widely taught frameworks categorize foods into five major groups: fruits, vegetables, grains (starches), proteins (meats, fish, eggs, legumes, nuts), and dairy (milk, cheese, yogurt). Some variations add fats/oils as a separate group or treat fats as part of the other groups.

Common frameworks and how they differ

• Five food groups (nutrition education standard):
  • Fruits
  • Vegetables
  • Grains (starches)
  • Proteins
  • Dairy
  • Note: Some sources also explicitly include fats and oils as a sixth group, or place them within another category as needed.
• MyPlate / USDA-style approach (United States):
  • Fruits
  • Vegetables
  • Grains
  • Protein
  • Dairy
• Other regional schemes sometimes use seven or more categories to reflect nutrient emphasis:
  • Carbohydrates/starches
  • Proteins
  • Dairy or fortified alternatives
  • Fruits
  • Vegetables
  • Fats and oils
  • Oils, nuts, seeds, and legumes (sometimes separated)
• Some older or more technical classifications (used in nutrition science) list macros and micronutrients, but for everyday dietary guidance, the five-to-seven group framework is most common.

How to apply this in practice

• Aim for variety: include foods from each group across daily meals.
• Balance portions: different groups contribute different nutrients, so a balanced plate typically features carbohydrates (grains), protein, and plenty of fruits/vegetables, with dairy or fortified alternatives.
• Special considerations: dietary restrictions, age, activity level, and cultural preferences may shift emphasis or require substitutions (e.g., plant-based proteins or lactose-free dairy options).

If you’d like, share your region or the context (school curriculum, health program, cookery class), and the answer can be tailored to that specific framework.