Performance

Caffeine

Also known as: 1,3,7-Trimethylxanthine, Coffee extract, PURENERGY, caffeine co-crystal

Evidence

Most widely used performance enhancer. Improves endurance, strength, and cognitive function through adenosine antagonism.

Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.

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Primary uses

Energy
Endurance
Focus
Strength
Thermogenesis
Fat oxidation
Appetite suppression

How it works

Blocks adenosine receptors
Increases catecholamines
Enhances fat oxidation
Central nervous system stimulant

Dosage

Typical range: 100-400 mg daily; 3-6mg/kg for performance
Timing: 30-60 min before exercise
With food: Optional
Duration: Tolerance develops; cycle
Special populations: Athletes, shift workers

Forms

Capsules/tablets
Powder
Coffee
Anhydrous
Natural (guarana, green tea)

Safety

Common side effects

Anxiety
Insomnia
Jitters
Dependency

Contraindications

Arrhythmias
Severe anxiety

Products containing Caffeine

Top-scoring supplements in our catalog that list Caffeine on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.

Nutricost

Caffeine + L-Theanine Capsules

Known interactions

Evidence notes

Proven ergogenic aid

Grade A: Multiple well-designed human trials support the main claims.

Cited research for Caffeine

Clinical studies referenced across Formulate guides that mention caffeine. Each links to the full study page with PubMed source + the guides that cite it.

Caffeine compared head-to-head

Caffeine Stacks
Caffeine vs Caffeine + Theanine Stack

Related in Performance

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.