Scientists have identified a remarkable protein switch that influences whether cells burn fat or store it. Disabling this protein increases fat consumption and interferes with the formation of new fat cells, raising the possibility of a different approach to treating obesity. Subsequent research has strengthened the discovery, revealing that the same protein helps regulate how much energy the body burns.

What if one of the keys to fighting obesity lies not in suppressing appetite, but in changing how the body's cells use energy?

Researchers at the Weizmann Institute of Science have identified a protein called MTCH2, nicknamed "Mitch," that plays an important role in controlling metabolism. When scientists disabled this protein in laboratory experiments, cells began consuming more fuel, including fats and carbohydrates.…