Leucine, an amino acid found in foods like beans, dairy and meat, may do more than help build muscle. It also appears to fine-tune how cells convert nutrients into energy.
Scientists at the University of Cologne found that leucine helps cells keep their mitochondria, the “powerhouses” that generate energy, running efficiently. The study, published in Nature Cell Biology, offers new insight into how nutrients do more than fuel the body. They also act as signals that tell cells when and how to make energy.
“We were thrilled to discover that a cell’s nutrient status, especially its leucine levels, directly impacts energy production,” said Qiaochu Li, Ph.D., the study’s first author. “This mechanism enables cells to swiftly adapt to increased energy demands during periods of nutrient abundance.”
The researchers found that when leucine is present, it helps protect the structures mitochondria use to pull in the building blocks for energy. This allows cells to stay flexible and respond more efficiently when energy demands rise, such as during exercise or recovery.
The discovery highlights how the body continually adjusts its metabolism based on nutrient availability. It also helps explain why a balanced intake of protein, including sources of essential amino acids like leucine, supports long-term health and vitality.
While the research was conducted in cells and model organisms, scientists say the findings could eventually inform studies on metabolism, aging and diseases that affect how the body produces and uses energy.
By uncovering how leucine helps sustain the body’s natural energy rhythm, researchers are one step closer to understanding how food acts as both fuel and information, shaping health all the way down to our cells.
This research was supported by Germany’s Excellence Strategy through the CECAD Cluster of Excellence on Aging Research, the German Research Foundation (DFG), the European Research Council, and the Alexander von Humboldt Foundation.