Taurine | Supplementopedia

Overview

Taurine (2‑aminoethanesulfonic acid) is a sulfur‑containing β‑amino acid.
It is not incorporated into proteins but exists freely in high concentrations across mammalian tissues.
High concentrations are found especially in the brain, retina, heart, and skeletal muscle.
It functions primarily as a conditional “essential” nutrient.
It supports osmoregulation, antioxidant defense, and calcium signaling.
These functions together underlie its many physiological roles.

Cardiovascular health: 1–3 g/day of taurine lowers systolic blood pressure by 2–4 mm Hg.
Cardiovascular health: It improves endothelial function (e.g., reduced arterial stiffness).
Exercise performance: Acute supplementation (1–6 g) improves time‑to‑exhaustion.
Exercise performance: It reduces muscle damage markers after high‑intensity exercise.
Exercise performance: These benefits are likely via enhanced calcium handling and reduced oxidative stress.
Metabolic regulation: Meta‑analyses report modest reductions in fasting glucose and triglycerides in people with metabolic syndrome.
Metabolic regulation: 1–3 g/day is taken for ≥12 weeks.
Neurological support: Taurine enhances cognition in animal models and small human trials.
Neurological support: It protects against excitotoxic injury.
Neurological support: This may be by modulating GABA‑ergic and NMDA‑receptor activity.
Retinal health: Long‑term supplementation (≥1 g/day) slows progression of diabetic retinopathy.
Retinal health: It improves visual acuity in clinical cohorts.
Retinal health: This reflects its role in retinal osmoregulation.

Pleiotropic molecule: Taurine functions as a “pleiotropic” molecule.
Cell membrane stabilization: It stabilizes cell membranes by interacting with phospholipid head groups.
Cell membrane stabilization: This preserves membrane integrity under osmotic stress.
Antioxidant activity: It scavenges hypochlorous acid and attenuates reactive oxygen species via the taurine‑chloramine pathway.
Calcium handling: Taurine modulates the sarcoplasmic reticulum Ca²⁺‑ATPase (SERCA) and voltage‑gated calcium channels.
Calcium handling: This improves cardiac contractility and skeletal‑muscle excitation‑contraction coupling.
Bile acid conjugation: It conjugates bile acids (forming taurocholate).
Bile acid conjugation: This enhances lipid digestion and cholesterol homeostasis.
Neuromodulation: In the central nervous system, taurine acts as a neuromodulator at GABA_A and glycine receptors.
Neuromodulation: This dampens neuronal excitability.
Anti-inflammatory signaling: It participates in the formation of taurine‑derived metabolites (e.g., taurine‑chloramine, taurine‑sulfonic acid).
Anti-inflammatory signaling: These metabolites mediate anti‑inflammatory signaling via NF‑κB inhibition.

Typical oral doses range from 500 mg to 3 g per day.
Cardiovascular support: 1–2 g/day divided into two doses (morning and evening) is common.
Cardiovascular support: Studies on blood‑pressure reduction used 1.5–3 g/day.
Athletic performance: A loading dose of 3 g 30 min pre‑exercise is often used.
Athletic performance: This is followed by 1 g post‑exercise for recovery.
Metabolic health: 1–2 g/day for 12–24 weeks has shown efficacy.
Taurine has high bioavailability (~90 %) and a half‑life of ~1.5 h.
Split dosing maintains steady plasma concentrations.
Individuals with renal impairment should limit intake to ≤1 g/day.
Individuals with renal impairment should monitor serum electrolytes.
Pregnant or lactating women should consult a healthcare professional before exceeding 1 g/day.

Taurine is generally recognized as safe (GRAS) up to 6 g/day in healthy adults.
Adverse events are rare and mild (e.g., nausea, headache).
No serious toxicity has been reported at typical supplemental doses.
Contraindications include severe renal impairment (eGFR < 30 mL/min/1.73 m²).
Reduced clearance may raise plasma levels in those with renal impairment.
Potential drug interactions include diuretics (may amplify hypokalemia).
Potential drug interactions include lithium (possible additive neuroprotective effects, but monitoring is advised).
Caution is advised for individuals on antihypertensives, as additive blood‑pressure lowering may occur.
Pregnant, lactating women, and children should use ≤1 g/day unless directed by a clinician.
Long‑term high‑dose (>6 g/day) data are limited.
Chronic dosing above this threshold is not recommended.

Taurine’s chemical formula is C₂H₇NO₃S.
Its molecular weight is 125.15 g·mol⁻¹.
Its IUPAC name is 2‑aminoethanesulfonic acid.
Structurally, it consists of an ethyl backbone.
It bears a primary amine (–NH₂) at C‑2 and a sulfonic acid group (–SO₃⁻) at C‑1.
This gives it a zwitterionic nature at physiological pH (pKa₁ ≈ 9.0 for the amine, pKa₂ ≈ 1.5 for the sulfonic acid).
The sulfonate group confers strong hydrophilicity and resistance to metabolic oxidation.
The amino group enables interaction with transporters (e.g., TauT, a Na⁺‑dependent taurine transporter).
The molecule is highly soluble in water (>1 g mL⁻¹).
It is stable across a wide pH range.
This facilitates both oral absorption and formulation stability.

Naturally, taurine is abundant in animal tissues.
It is especially abundant in seafood, meat, and dairy.
It exists as a free amino acid in these tissues.
Commercially, taurine is produced primarily by a two‑step synthetic pathway.
(1) ethylene oxide reacts with aqueous ammonia to give 2‑aminoethanol.
(2) 2‑aminoethanol is then oxidized with sulfur dioxide to form the sulfonic acid group.
This yields high‑purity (>99 %) taurine.
Fermentation‑based biotechnological processes using E. coli engineered for taurine biosynthesis are emerging as “green” alternatives.
For supplements, pharmaceutical‑grade taurine must meet USP or EP monographs.
These specify limits on heavy metals (<10 ppm) and residual solvents (<0.1 %).
Third‑party testing (e.g., NSF, In‑Form) is recommended.
This verifies purity and absence of contaminants such as heavy metals or microbial toxins.