What kind of diet does a olympic swimmer eat?

Yeah diet makes a big difference.

Cut down on foods high in fat. (i.e. fast food). Protein is good for building muscle for sprinters. Complex carbohydrates work for distance. Don't drink a lot of pop.

Swimmers should consume from 60-70% of daily calories in carb-rich foods.

Limit intake of fat to 15-20% of daily calories, or less than 80 grams. Recommended daily protein is 20-25% of total calories. Take vitamins A, C and E.