Move over, multivitamins.
New research suggests a little-known supplement could help protect people from severe illness or death after injury or infection, potentially giving the body an extra edge when it’s under attack.
The findings offer fresh insight into what scientists call the “disease trajectory” and how simple lifestyle changes might help steer people off a fast track toward decline and back on the road to recovery.
“Our study indicates that small biological differences, including dietary factors, can have large effects on disease outcomes,” Dr. Janelle Ayres, a professor at the Salk Institute for Biological Studies and the study’s senior author, said in a statement.
The researchers focused specifically on methionine, an essential amino acid the body can’t produce on its own and must get from food.
Methionine can be found in protein-rich staples like eggs, poultry, fish and beef, as well as plant-based options such as Brazil nuts, sesame seeds, soybeans, tofu, lentils and whole grains like quinoa. It’s also available in supplement form, typically in the form of L-methionine.
Methionine plays several important roles in the body, building proteins, supporting DNA activity and repairing damaged tissues. But Ayres and her colleagues were especially interested in its role in controlling inflammation, the immune system’s built-in fire alarm.
Inflammation kicks in whenever the body senses a threat, like an injury or infection. Immune cells swarm the area and release chemical messengers called pro-inflammatory cytokines, which coordinate the attack and kick-start the healing process.
But too much of a good thing can seriously backfire.
When inflammation spirals out of control, it can damage healthy cells and lead to organ damage and tissue death. That can trigger intense symptoms of illness and lead to serious complications, like fluid buildup in the lungs.
If the immune response never gets turned down, it can turn into chronic, low-grade inflammation — a major driver of aging and diseases like cancer, diabetes and heart disease.
“Pro-inflammatory cytokines are ultimately what leads to sickness and death in a lot of cases,” Dr. Katia Troha, a postdoctoral researcher in Ayres’s lab and first author of the study.
“The immune system has to balance inflammation to attack the invader without harming healthy cells in the body. Our job is to find the mechanisms it uses to do that, so that we can target them to improve patient outcomes.”
To see how that balance works, researchers used mice with systemic inflammation caused by the bacterium Yersinia pseudotuberculosis.
They quickly noticed the sick mice were eating less, a sign that their metabolism was changing.
When the researchers checked their blood, they that their methionine levels had dropped.
That sparked an idea. Troha fed a new group of mice chow supplemented with methionine and found that they were protected against the infection.
Digging deeper, the team discovered methionine was working with an unexpected partner: The kidneys.
The amino acid boosted kidney filtration and blood flow, helping the body flush excess inflammatory cytokines out through urine.
Importantly, this didn’t weaken the mice’s ability to fight infection. Their immune systems still did the job, just without the collateral damage.
The team then tested methionine in other models, including sepsis and kidney injury, and saw similar protective effects.
That suggests methionine could have broader potential in inflammatory diseases — especially those involving kidney stress or failure.
“Our findings add to a growing body of evidence that common dietary elements can be used as medicine,” Ayres said.
Still, researchers stress that the results are based on animal studies — so there’s no need to sprint to the supplement aisle just yet.
Next, the team plans to dig deeper into how methionine works, whether other amino acids offer similar perks, and how these findings might translate to humans.
“By studying these basic protective mechanisms, we reveal surprising new ways to shift individuals that are fated to develop disease and die onto trajectories of health and survival,” Ayres said.
“It may one day be possible for something as simple as a supplement with dinner to make the difference between life and death for a patient.”
