The simplest amino acid · validated by the NIA ITP (Miller 2019) as geroprotector in male mice. Critical glutathione precursor, improves sleep architecture by lowering core temperature pre-deep sleep, and modulates GABA. Attia/Patrick canon for nighttime protocol.
6Glycine appears in 6 protocols personalizable→Simplest amino acid · non-essential but conditionally essential in elders · needed for collagen, glutathione, inhibitory neurotransmission.
Glycine (Gly) is the simplest amino acid: a molecule with a single CH2-NH2 group. But its simplicity hides critical functions: 33% of collagen residues are glycine (triple helix structure), glutathione precursor (along with cysteine and glutamate), inhibitory modulator in central nervous system, substrate for creatine and porphyrins.
Although classified as «non-essential» (synthesized endogenously), endogenous synthesis drops drastically with age. Adults >65 years have glutathione levels up to 50% lower than young · much due to functional deficiency of glycine as limiting substrate (Sekhon 2018).
Its supplemented use focuses on three areas: (1) improving sleep architecture by lowering core temperature 0.3°C pre-deep sleep · activates hypothalamic NMDA receptors (Bannai 2012); (2) glutathione precursor combined with NAC ("GlyNAC") · Sekhon 2021 reversed aging hallmarks in humans >70; (3) NIA ITP geroprotector · Miller 2019 demonstrated lifespan extension in male mice.
5 pivotal studies · NIA ITP + GlyNAC trial + sleep RCT + endogenous collagen.
| Study | Finding | Hallmarks |
|---|---|---|
NIA ITP · glycine extends male mice lifespan Miller et al · Aging Cell 2019 | NIA interventional testing program · 4% dietary glycine extended median male mouse lifespan 4-6% (positive results in 3 of 3 centers · robust replication). No effect in females (higher endogenous synthesis). | LongevityITP-NIA |
GlyNAC · reverses aging hallmarks in humans Sekhon et al · Clin Transl Med 2021 | 16-week RCT · n=24 adults 70-80 years · glycine + NAC combo improved glutathione, mitochondrial function, insulin sensitivity, grip strength, walking speed, cognitive impairment. Aging hallmarks substantially improved. | GlutathioneMito |
Pre-sleep glycine and subjective quality Bannai & Kawai · Front Neurol 2012 | Crossover RCT n=11 volunteers with mild insomnia · 3 g pre-sleep glycine lowered core temperature, improved PSQI score, reduced daytime sleepiness and improved morning cognitive performance vs placebo. | SleepThermoreg. |
Glycine deficient with age · collagen synthesis Meléndez-Hevia et al · J Biosci 2009 | Biosynthetic analysis · adult needs ~15 g/day glycine to maintain collagen · max endogenous synthesis ~3 g + typical diet ~2 g = functional deficit 10 g/day. Recommendation: 10 g/d supplementation for adults post-30. | CollagenAge |
Glycine and inflammation resolution Zhong et al · Nutrients 2022 | Mechanistic review · glycine activates inhibitory Gly-R receptor in inflammatory cells (macrophages, Kupffer), reduces TNF-α and IL-6. Anti-inflammatory effects in hepatic ischemia-reperfusion damage + endotoxemia + sepsis. | Inflamm.Hepatic |
My Protocol generates 3 personalized plans with exact form, dose and combos based on your profile. No commitment.
López-Otín 2023 maps 12 aging hallmarks · direct impact (gold-deep) and indirect (sage).
Two parallel protocols · 3-5 g pre-sleep (sleep effects) + 10 g distributed in day (collagen/glutathione). Can be combined.
Dissolve in warm water (pleasant sweet taste). Lowers core temperature 0.3°C activating hypothalamic NMDA · facilitates deep sleep transition. Notable subjective effect in 1-2 weeks.
For collagen maintenance (skin, joints, tendons) + glutathione substrate. Melendez-Hevia 2009 dose · can be taken in coffee (doesn't alter taste) or water. Combinable with Protocol A.
Sekhon 2021 combo · reverses aging hallmarks in elders >65 · effect on glutathione, mitochondria, insulin sensitivity. Maintain 12+ weeks to see effects.
Anti-inflammatory + tendinous collagen substrate. Common combo with vitamin C 500 mg for accelerated collagen synthesis (Shaw 2017).
One chemical form (free glycine) · differences only in format and price. Bulk powder is the absolute winner by economy.
3 tiers · USP pharmacopoeia purity (≥99.5%) · no artificial flavors. Bulk powder is absolute cost/efficacy winner.
Dose: 3 g glycine + 1 g NAC / serving
Form: L-Glycine + N-acetylcysteine · Sekhon ratio
Cert.: NSF · GMP · third-party tested
Fillers: Zero · only free amino acids
Dose: 3-5 g / serving (measuring spoon)
Form: L-Glycine USP grade · crystalline powder
Cert.: Informed Sport · GMP
Fillers: Zero · 100% pure glycine
Dose: 3 g / serving
Form: L-Glycine · powder
Cert.: GMP · Non-GMO
Fillers: Zero
My Protocol recommends form + brand + exact dose based on your age, budget and biomarkers. No commitment · 3 minutes.
3 biomarkers · one direct (glutathione), two indirect (sleep, inflammation markers).
RBC glutathione (GSH/GSSG ratio). Direct marker of endogenous antioxidant function · supplementing glycine + NAC raises ratio in 8-12 weeks. ~45 € in Spanish private analytics.
Sleep quality (PSQI or tracker). PSQI <5 indicates good quality. Tracker (Whoop · Oura · Garmin) shows +5-15 min absolute deep sleep + awakening reduction in 1-2 weeks with 3 g pre-sleep.
High-sensitivity CRP. Target hs-CRP <1 mg/L · glycine reduces chronic inflammaging modulating TNF-α + IL-6. Detectable changes in 8-12 weeks (Sekhon 2021).
RBC glutathione + hs-CRP + IL-6 + omega-6:3 ratio. Complete panel evaluates antioxidant + anti-inflammatory effect of supplementation.
Excellent safety profile · few contraindications specific to renal and psychiatric conditions.
4 combos with cardinal RCT · glycine alone is good, in combo it's exceptional.
GlyNAC Sekhon 2021 combo · limiting glutathione substrates · reverses aging hallmarks in elders >65 · gold standard amino-based anti-aging.
Mg-glycinate ALREADY provides glycine as ligand · adding 3 g extra glycine pre-sleep potentiates sleep + GABAergic effect. Attia/Patrick canon.
Glycine (33% collagen) + vit C (proline hydroxylation cofactor) + hydrolyzed collagen = collagen synthesis trifecta (Shaw 2017 for tendons).
Apigenin inhibits CD38 (NAD+ degrader) · combo with nighttime glycine for sleep + NAD+ pool protocol. Emerging protocol.
8 real questions · scientific literature answers.
Supplements · treatments · biomarkers for your complete protocol.
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