Consider the delicate web of fat in a Wagyu (waa·gyoo) steak. The “marbling” that makes carnivore connoisseurs swoon is a visual heuristic for quality flavor.

Now, a new study from researchers at the University of Florida suggests the very same marbling of fat inside our own muscles points to trouble. This condition, known as intramuscular adipose tissue, has long been recognized by scientists as a strong indicator of poor health.

It’s linked to a wide range of diseases: obesity, Type 2 diabetes, neuromuscular disorders (including Duchenne muscular dystrophy) and neurogenerative conditions such as ALS. In some cases, clinicians can even track the progress of a disease by the amount of fat in muscle tissue.

In the study, researchers sought to understand the precise function this might play on muscle health, suspecting it could act as a driver of declining muscle function. The team developed a genetic model that allowed researchers to damage the muscle while preventing the infiltration of intramuscular fat.

When fat cells were present in the muscle, the muscle fibers were unable to properly form and grow. The fat tissue’s roadblock led to a disorganized and chaotic healing process that ultimately resulted in smaller, weaker muscle fibers. This directly translated to a loss of strength. Where space is occupied by fat cells, muscle fibers cannot grow.

Ultimately, these findings tell us more about the role of fat in muscle disease and aging. Future solutions might focus on decreasing or removing the physical blockage of fat, rather than just muscle growth…like removing a pebble in the way of a struggling sprout. Once it’s gone, something healthier might have room to grow.