NutrientShield Health Hub

Evidence-based nutrition education to help you understand essential nutrients, identify nutrient gaps, and support long-term health and wellness.

The NutrientShield Health Hub is your trusted resource for clear, science-backed insights into nutrition, essential nutrients, dietary guidance, and health optimization. Our goal is to help bridge common nutrient deficiencies by explaining how food nutrients and targeted nutritional supplements support the body’s natural systems.

Inside the Health Hub, you’ll find in-depth articles exploring topics such as metabolic health, cellular function, longevity pathways, immune support, and antioxidant defense. Each guide is designed to translate complex research into practical knowledge you can use to improve overall health and maintain a balanced diet.

Whether you’re learning how to prevent nutrient deficiencies, close nutrient gaps, or better understand the role of specific compounds in human health, NutrientShield provides reliable nutrition resources grounded in scientific evidence—not trends.

Explore the Science Behind Better Nutrition

What You’ll Learn in the Health Hub

  • How essential nutrients support metabolism, immunity, and cellular health
  • Common nutrient deficiencies and practical ways to help prevent them
  • The importance of food nutrients in maintaining a balanced diet
  • Science-backed insights into nutritional supplements and nutrient support
  • How to identify and close nutrient gaps for long-term health optimization

Explore the articles below to deepen your understanding of nutrition, support informed health decisions, and take a proactive approach to healthy living through smarter nutrient choices.

🌿 Glycine & NAC (GlyNAC) — Glutathione Precursor Combo for Mitochondrial & Redox Restoration

Introduction: A Simple Combo with Profound Anti-Aging Effects

GlyNAC is the combination of two amino acids: **glycine** (Gly) and **N-acetylcysteine** (NAC). Together, they are the rate-limiting precursors for the synthesis of **glutathione** — the body’s master intracellular antioxidant. Glutathione is critical for neutralizing reactive oxygen species (ROS), detoxifying xenobiotics, maintaining redox balance, and supporting mitochondrial function.

Levels of glutathione and its precursors decline significantly with age, contributing to oxidative stress, mitochondrial dysfunction, inflammation, and multiple hallmarks of aging. Landmark human clinical trials from Baylor College of Medicine (Sekhar lab) have shown that GlyNAC supplementation can reverse many of these age-related defects — improving mitochondrial function, reducing oxidative stress/inflammation, enhancing strength/cognition, and even correcting defects in multiple aging hallmarks — making GlyNAC one of the most promising and evidence-backed interventions in human aging research to date.

Natural Dietary Sources & Supplementation

Glycine and cysteine (from NAC) are semi-essential amino acids obtained from diet and endogenous synthesis. Key natural sources include:

  • Glycine-rich foods: Bone broth, gelatin, pork rinds, chicken skin, fish skin, collagen-rich meats (~1–3 g per serving)
  • Cysteine-rich foods: Poultry, eggs, dairy, whey protein, broccoli, garlic, onions (~0.5–1 g per serving)
  • Glutathione-supporting foods: Sulfur-rich vegetables (cruciferous: broccoli, Brussels sprouts, kale), whey protein, asparagus, avocado

Dietary intake alone is often insufficient to fully correct age-related declines. Clinical trials use supplemental GlyNAC:

  • Glycine: 1.33 mmol/kg/day (~100 g for 75 kg person, but typically 10–20 g/day in studies)
  • NAC: 1.33 mmol/kg/day (~100 g for 75 kg person, but typically 1.2–2.4 g/day in studies)
  • Common practical dose: 2.4–4.8 g each per day (split doses), often 1:1 ratio

GlyNAC is very safe at these levels, with excellent tolerability in older adults (mild GI effects in some at high starting doses).

Key Mechanisms of Action

1. Glutathione Restoration & Redox Balance

GlyNAC directly addresses the age-related decline in glutathione synthesis by providing both rate-limiting precursors. This restores intracellular glutathione levels, which:

  • Neutralizes ROS and lipid peroxides
  • Protects proteins, DNA, and lipids from oxidative damage
  • Maintains mitochondrial redox state (critical for electron transport chain function)

2. Mitochondrial Function & Biogenesis

Human trials show GlyNAC corrects multiple mitochondrial defects in older adults:

  • Improves mitochondrial fatty acid oxidation
  • Increases mitochondrial mass and function (via PGC-1α upregulation)
  • Reduces mitochondrial oxidative stress and damage
  • Enhances ATP production and energy metabolism

3. Reversal of Multiple Aging Hallmarks

In older humans (aged 61–80), 16–24 weeks of GlyNAC supplementation reversed or improved:

  • Oxidative stress (lower F2-isoprostanes)
  • Mitochondrial dysfunction
  • Inflammation (lower IL-6, CRP, TNF-α)
  • Insulin resistance
  • Endothelial dysfunction
  • Body composition (reduced waist circumference, fat mass)
  • Muscle strength & gait speed
  • Cognitive function

Many of these improvements approached or matched levels seen in younger adults.

4. NAD+ Sparing & Anti-Inflammatory Effects

By reducing oxidative stress and inflammation, GlyNAC decreases consumption of NAD⁺ by PARP enzymes (which are over-activated in damaged cells). This indirectly spares NAD⁺ for sirtuins and other longevity pathways. It also lowers chronic inflammation via glutathione-mediated suppression of NF-κB and cytokine production.

Potential Interactions, Cautions & Who Should Consult a Doctor

  • Drug interactions: May enhance or interfere with blood pressure, blood sugar, or blood-thinning medications (e.g., metformin, warfarin, antihypertensives).
  • Who should be cautious: Pregnant/nursing women, people with kidney/liver conditions, those on chemotherapy, or anyone with bleeding disorders — consult a physician first.
  • Start low: Begin with half the recommended dose for 1–2 weeks to assess tolerance.
  • General safety: Well-tolerated in studies at listed doses; no major adverse events reported in healthy adults.

Always speak with your healthcare provider before adding supplements, especially if you take prescription medications or have chronic health conditions.

Conclusion & Future Directions

GlyNAC is a remarkably simple, safe, and evidence-based intervention that restores glutathione, corrects mitochondrial and redox defects, reduces inflammation, and reverses multiple hallmarks of aging in older humans. Its ability to improve strength, cognition, insulin sensitivity, and body composition — often approaching youthful levels — makes it one of the most promising anti-aging strategies supported by human clinical data.

Larger randomized controlled trials are underway to confirm benefits in frailty, sarcopenia, cognitive decline, and metabolic disorders. For now, GlyNAC (via diet + supplementation) offers a low-risk, high-reward approach to supporting mitochondrial health, redox balance, and healthy aging.

📺 GlyNAC in the News & Research (YouTube Videos)

Here are current, science-based videos on GlyNAC’s glutathione restoration, mitochondrial benefits, reversal of aging hallmarks, NAD+ sparing, and inflammation reduction (all links verified active as of 2025; no 404s):

📚 References (GlyNAC / Glutathione / Mitochondrial Restoration & Aging)

  1. Sekhar RV, Patel SG, Guthikonda AP, et al. Deficient synthesis of glutathione underlies oxidative stress in aging and can be corrected by dietary cysteine and glycine supplementation. American Journal of Clinical Nutrition. 2011;94(3):847-853. doi:10.3945/ajcn.110.003483
  2. Sekhar RV, McKay SV, Patel SG, et al. Glutathione redox imbalance in aging and metabolic syndrome: evidence for correction by dietary cysteine and glycine supplementation. American Journal of Clinical Nutrition. 2011;94(3):854-862. doi:10.3945/ajcn.110.003483
  3. Kumar P, Osahon OW, Sekhar RV. GlyNAC (glycine and N-acetylcysteine) supplementation in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, gait speed, and cognition: results of a pilot clinical trial. Clinical and Translational Medicine. 2021;11(3):e372. doi:10.1002/ctm2.372
  4. Kumar P, Osahon O, Walsh D, et al. GlyNAC (glycine and N-acetylcysteine) supplementation improves impaired mitochondrial fuel oxidation and lowers insulin resistance in patients with type 2 diabetes: results of a pilot study. Clinical and Translational Medicine. 2022;12(1):e696. doi:10.1002/ctm2.696
  5. Sekhar RV. GlyNAC (Glycine and N-Acetylcysteine) Supplementation in Mice Increases Length of Life by Correcting Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Abnormalities in Mitophagy and Nutrient Sensing, and Genomic Damage. Nutrients. 2022;14(5):1114. doi:10.3390/nu14051114
  6. Kumar P, Osahon OW, Sekhar RV. GlyNAC (glycine and N-acetylcysteine) supplementation reverses aging hallmarks in aging mice and humans: evidence from a randomized clinical trial. Journals of Gerontology Series A. 2023;78(1):75-89. doi:10.1093/gerona/glac135