Simple gardening with the 3 sisters can provide all you need in nutrition to feed you family.
The three crops benefit from each other. The maize provides a structure for the beans to climb, eliminating the need for poles. The beans provide the nitrogen to the soil that the other plants utilize, and the squash spreads along the ground, blocking the sunlight, helping prevent establishment of weeds.
Maize lacks the amino acids lysine and tryptophan, which your body needs to make proteins and niacin, beans contain both and therefore maize and beans together provide a balanced diet.