Zinc bisglycinate — The Highly Bioavailable Immunomodulator
Zinc bisglycinate is a highly bioavailable, chelated form of the essential trace mineral zinc, which is critical for immune function, DNA repair, and antioxidant defence. Because zinc deficiency becomes more common with age and drives immunosenescence and systemic inflammation, maintaining optimal zinc status is a foundational strategy for healthspan preservation.
Mechanism of Action
Zinc is an essential structural and catalytic component for over 300 enzymes and 2,000 transcription factors. In the context of longevity, zinc plays a critical role in maintaining immune function (immunosenescence prevention) and reducing chronic sterile inflammation (inflammaging). It inhibits the NF-κB pathway, thereby downregulating the production of pro-inflammatory cytokines such as TNF-α and IL-1β. Furthermore, zinc is required for the function of Cu/Zn superoxide dismutase (SOD1), a primary cellular antioxidant enzyme, and supports DNA repair mechanisms.
Human Trial Evidence
Multiple human trials confirm zinc bisglycinate is highly bioavailable, with one pharmacokinetic study (Gandia et al., 2007) showing it is 43.4% more bioavailable than zinc gluconate. Clinical trials in humans demonstrate that zinc supplementation reduces the duration of respiratory infections and modulates inflammatory markers, though specific long-term longevity trials using the bisglycinate form are lacking.
Dosing Protocol
15–30 mg of elemental zinc per day is the standard supplemental range. Best taken with food to minimise gastrointestinal upset. Doses exceeding 40 mg/day long-term require copper supplementation (typically 1–2 mg) to prevent copper deficiency.
Safety & Contraindications
Generally well tolerated at standard doses. The most common adverse effects are gastrointestinal, including nausea and stomach upset, though the bisglycinate chelate typically causes fewer GI issues than inorganic salts. Long-term supplementation above 40 mg/day can induce copper deficiency and impair immune function. May interact with certain antibiotics (tetracyclines, quinolones) and penicillamine, reducing their absorption.