Are lentils vegetables or grains?

According to the USDA, lentils are part of the vegetable group, but they also fall under the protein group — which is why many people consume lentils as a supplement for meat in a vegetarian diet. Lentils are an excellent source of plant protein, and they are also rich in zinc, iron, potassium and folate.

In terms of balancing the diet and meal planning, those who eat meat, fish and poultry should consider lentils as vegetables. Vegans and vegetarians who rarely or never eat meat, fish or poultry should consider lentils as a source of protein.