Protein

Protein—an important nutrient that helps build, maintain, and repair body tissue—is widely available in beans, vegetables, and grains. Protein deficiency is almost unheard of in the United States. It’s easy to get all the protein you need without eating meat, dairy, or eggs.

An average woman needs about 46 grams of protein per day; the average man about 56. But most Americans consume about double the amount they actually need. 

And when it comes to protein, more isn’t always better. One study found that people eating large amounts of animal protein have 23 times the risk of death from diabetes and 5 times the risk of death from cancer as those consuming less protein. Foods rich in animal protein are often packed with saturated fat and cholesterol.

High-protein diets for weight loss, disease prevention, and enhanced athletic performance have been greatly publicized over recent years. However, these diets are supported by little scientific research. Studies show that the healthiest diet is one that is high in carbohydrate, low in fat, and adequate in protein.