Soy is a type of bean that grows on plants originally from East Asia and is now cultivated worldwide. Soybeans are incredibly versatile and appear in countless foods: tofu, soy milk, soy sauce, edamame (the green pods you might find at a Japanese restaurant), and even many vegetarian burgers and meat substitutes.

What makes soybeans special is their high protein content. While most beans have some protein, soybeans have so much that they can serve as a main protein source in meals, which is why they've been central to Asian cuisine for thousands of years. Farmers also value soybeans because, like other legumes, they naturally enrich soil with nitrogen, making the ground more fertile for future crops.

You'll often see “soy” listed on food labels. Soy lecithin helps ingredients blend smoothly in chocolate bars and salad dressings. Soybean oil is one of the most common cooking oils in America. Some people avoid soy due to allergies, which is why packages often note when they contain it.

The word can also describe products made from soybeans: soy milk as an alternative to dairy milk, or soy protein in nutrition bars and shakes.