It’s the first rule of healthy eating: eat a wide variety of foods.
The U.S. Department of Agriculture and the U.S. Department of Health and Human Services (USDA and DHHS, 1980) advises you to consume something from all 5 major food groups: fruits and vegetables, (whole) grains, meat, poultry, fish and legumes, dairy products, and fats and sweets. You should also try to vary with ingredients within each food group.
But did you know that on average, we only eat 25 different kinds of foods in 3 days? In contrast, research suggests that our hunter-gatherer ancestors used to collect over 55 unique plants to secure food all year round. That’s a pretty big difference! But why should you want to bring more variation to your daily diet?