A Nutrient Boost Might Come at a Cost to Longevity

There’s a nutrient that’s often thought to enhance mental clarity, but it may also cut years off your life.

Recent research indicates that a commonly used supplement ingredient, known for its ability to heighten focus and cognitive function, could have an unexpected downside regarding lifespan.

The study revealed that men with elevated levels of this nutrient in their bloodstream generally had shorter lifespans, whereas women seemed to be unaffected.

Conducted by researchers from the University of Hong Kong and the University of Georgia, the research looked at health and genetic data from over 270,000 individuals in the UK Biobank.

Specifically, they examined two amino acids — phenylalanine and tyrosine — to see if they had any influence on aging.

These amino acids are crucial for protein construction in the body, but tyrosine also assists in creating dopamine, adrenaline, and other brain chemicals related to mood, concentration, and stress management.

Meanwhile, phenylalanine converts into tyrosine within the body. Both of these amino acids can be found in protein-rich foods and are frequently added to dietary supplements.

To explore their impact on longevity, the researchers initially assessed the blood levels of participants and compared these to their mortality rates and anticipated lifespan.

Employing a method known as Mendelian randomization—a genetic analysis technique—they aimed to discern whether one factor could directly affect another.

The results showed that men with higher blood levels of tyrosine tended to live shorter lives, with an increase in levels correlating to nearly a year less on average. Interestingly, women did not show a similar pattern.

The researchers noted, “Phenylalanine showed no association with lifespan in either men or women after controlling for tyrosine.”

While the exact reasons behind this correlation are still unclear, scientists have several hypotheses.

One possible explanation relates to insulin resistance—a condition where the body’s cells become less responsive to insulin, which regulates blood sugar levels.

Tyrosine is vital for the signaling that enables insulin to prompt cells to absorb sugar from the blood. Although it’s essential for normal cellular activity, too much tyrosine in the bloodstream might interfere with this signaling process.

Insulin resistance can lead to various health issues that typically become more prevalent with aging — such as neurodegenerative conditions, high blood pressure, cardiovascular problems, and Type 2 diabetes — all of which could impact lifespan.

Moreover, tyrosine’s role in producing certain brain chemicals associated with mood and stress could also contribute to this phenomenon.

The researchers proposed that variations in these chemicals between genders might clarify why the lifespan connection was observed in men but not in women.

They even speculated that tyrosine might play a part in the well-known longevity gap between men and women. However, they emphasized that their study does not establish a direct cause-and-effect relationship regarding lifespan differences.

Despite these intriguing findings, the results shouldn’t lead you to toss out your supplements. The researchers didn’t directly evaluate specific products containing tyrosine, nor was there evidence suggesting that taking these supplements will reduce your lifespan.

In fact, other studies have indicated that tyrosine can contribute positively to mental focus, memory enhancement, and cognitive function, especially under stress.

The researchers suggested that individuals with unusually high blood concentrations of tyrosine might benefit from dietary adjustments to lower those levels.

Foods rich in tyrosine include chicken, turkey, beef, lamb, fish, hard cheeses, eggs, sesame seeds, soybeans, and various nuts.