Caffeine or Theacrine?

Both items are reviewed in the reference. Below their characteristics sit side by side as the studies describe them. This is a comparison of data, not advice on what to choose.

	Caffeine	Theacrine
evidence level	A	C
Sources in the review	3	1
Category	For the goal	Overrated
Goals	Endurance, Strength, Fat loss	Endurance, Strength, Fat loss
Dosage	3-6 mg/kg per serving; 200 mg also works. Doses above 9 mg/kg give no increase in effect but increase adverse effects. The form is caffeine or coffee.	100–300 mg per day; studies used doses of 125, 200 and 300 mg. No effective dose for improving performance could be established
When to take	45-60 minutes before exercise. With regular use the effect partially weakens, so caffeine-free periods are reasonable.	No regimen giving a reproducible effect has been established. It is usually suggested 30–60 minutes before exercise

The conclusion from the data. In the reference «Caffeine» Level A and 3 sources, while «Theacrine» — Level C and 1. A higher level means the effect is better supported by research, not that the item suits you better.

Verdicts

Caffeine

A working supplement: endurance +2–4%, strength moderately

Theacrine

The effect is NOT confirmed: a 2025 study revealed no improvement

Sources for both items

Other comparisons

Creatine monohydrate or Creatine HCl Creatine monohydrate or Creatine nitrate Whey protein or Casein protein Whey protein or Pea protein Pea protein or Rice protein Soy protein or Whey protein BCAA (branched-chain amino acids) or Essential amino acids (EAA) Citrulline malate or Arginine