C
Weight LossStrong Evidence3rd Party Tested

Caffeine

Also known as: Caffeine Anhydrous, 1,3,7-trimethylxanthine

The world's most studied metabolic and performance stimulant

9/10 Evidence Score

Primary Benefit

Metabolic Rate & Fat Oxidation

Standard Dose

100 to 200 mg per dose

Evidence

Certifications

Informed SportNSF Certified for Sport

Overview

Caffeine is the most widely consumed psychoactive substance in the world and one of the most rigorously studied weight loss aids. It increases metabolic rate, enhances fat oxidation, suppresses appetite, and significantly boosts exercise performance, making it a central ingredient in virtually every evidence-backed fat-loss protocol.

Benefits & Evidence

  • Increases resting metabolic rate by 3 to 11 percent
  • Enhances fat oxidation during exercise
  • Suppresses appetite, reducing caloric intake
  • Significantly improves exercise performance and endurance
  • Boosts thermogenesis and energy expenditure

Clinical Study Summaries

Caffeine intake increases plasma ketones: an acute metabolic study in humans

2016

Canadian Journal of Physiology and Pharmacology

Caffeine significantly increased fat oxidation and ketone production, suggesting enhanced lipid mobilization as a metabolic fuel.

View study

The effect of caffeine on energy balance

2019

Journal of Basic and Clinical Physiology and Pharmacology

Caffeine consumption acutely increased metabolic rate and fat oxidation, with consistent evidence of short-term negative energy balance.

View study

Recommended Dosage

Standard Dose100 to 200 mg per dose
Minimum50 mg
Maximum400 mg/day
Timing30 to 60 minutes before exercise or meals
Notes: Tolerance develops with chronic use. Cycling off for 1 to 2 weeks every month maintains sensitivity. Caffeine anhydrous is the most studied form for weight loss.

Side Effects & Interactions

Potential Side Effects
  • Jitteriness and anxiety at high doses
  • Insomnia if taken too late in the day
  • Elevated heart rate and blood pressure
  • Dependence and withdrawal headaches
  • GI discomfort in sensitive individuals
Drug & Nutrient Interactions
  • Stimulant medications (additive cardiovascular strain)
  • MAOIs (potentially dangerous combination)
  • Beta-blockers (may reduce effectiveness)
  • Creatine (may partially offset benefits at very high doses)

Who Should Consider It

Good candidates

  • Individuals seeking a metabolic boost during a caloric deficit
  • Athletes wanting improved fat burning during cardio
  • People who tolerate caffeine well with no anxiety disorders

Use caution or avoid

  • Those with anxiety disorders or heart arrhythmias
  • Pregnant or breastfeeding individuals
  • People sensitive to stimulants
  • Those with high blood pressure not under medical management
Medical Disclaimer

This information is for educational purposes only. It does not constitute medical advice. Consult a qualified healthcare professional before starting any supplement, especially if you have health conditions or take medications.

Third-Party Testing

This supplement has products available with independent quality verification.

Informed Sport
NSF Certified for Sport
Evidence Breakdown
Overall Score9/10
Popularity10/10

Evidence Level

Strong

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