The primary source of protein in a vegetarian diet is legumes, which include beans, lentils, and peas. These protein-rich foods are essential for vegetarians to meet their dietary needs without consuming meat. Legumes are not only high in protein but also provide dietary fiber, vitamins, and minerals. Other important vegetarian protein sources include tofu, tempeh, nuts, seeds, and dairy products for lacto-vegetarians. Combining different plant-based proteins can help ensure a complete amino acid profile, which is crucial for overall health and wellness.