The Newest Anti-Aging Discovery: Two Nutrients That May Rewind Your Biological Age for up to 4 years

What if a simple daily supplement could turn back your biological clock—not just in theory, but in a way, science can measure?

That’s exactly what a new clinical study from 2025 has shown with a combination of two natural compounds: glycine and N-acetylcysteine. When taken together for just a few months, they helped older adults become biologically almost 4 years younger.

Sounds like science fiction? It’s not. Let’s break it down.

What Are Glycine and N-Acetylcysteine?

Glycine is one of the simplest and most common amino acids—the building blocks of protein. Our body produces some of it naturally, and we also get it from food (especially meat, fish, dairy, and legumes). It helps build tissues, supports brain health, promotes restful sleep, and plays a role in detoxification and collagen formation.

N-Acetylcysteine (NAC) is a modified form of the amino acid cysteine. It helps the body produce glutathione, one of our most important natural antioxidants. Glutathione protects our cells from damage caused by aging, stress, and environmental toxins.

Both compounds are well-known, studied, and widely used in clinical and nutritional practice.

The Study That Got Everyone’s Attention

Researchers at Baylor College of Medicine (USA) conducted a randomized, placebo-controlled clinical trial with healthy older adults aged 61 to 80. Over a period of 16 weeks, participants received a daily combination of glycine and NAC.

The results showed measurable improvements in several key areas:

• Improved mitochondrial (cellular energy) function

• Increased physical strength and walking speed

• Enhanced cognitive performance

• Reduced inflammation and oxidative stress

• Better blood sugar and lipid balance

But the most eye-opening result was this:

Participants' biological age decreased by 2.5 to 4.1 years, as measured by a method called phenotypic age—an evidence-based estimate of how “old” the body functions internally, regardless of chronological age.

What Does This Mean?

For older adults—and for anyone thinking ahead about healthy aging—this study suggests that two simple, well-understood nutrients may have a real impact on slowing or even reversing the physical signs of aging. These changes weren't just subjective feelings of improvement, but objective, measurable biological shifts observed within just a few months.

Glycine and NAC are not experimental, expensive, or difficult to access. They’re already available in pharmacies and health food stores worldwide, making this one of the most accessible science-backed anti-aging strategies to emerge in recent years.

Reference: Sekhar, R. V., Patel, S. G., Guthikonda, A. P., Reddy, V. T., Balasubramanyam, A., & Jahoor, F. (2025). Supplementing glycine and N-acetylcysteine (GlyNAC) in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, physical function, and aging hallmarks: A randomized clinical trial. Innovation in Aging, 8(Suppl 1), 250.