The term SUBSTANCE IN WHEAT can be answered with the 6-letter word GLUTEN. Gluten is a protein found in wheat, barley, and rye, and is responsible for the elasticity of dough. It is also found in many processed foods, such as breads, pastas, and cereals. Gluten has become a controversial topic in recent years due to its potential health risks for those with gluten sensitivities or celiac disease.