Ephedrine vs T3 (Cytomel): side-by-side comparison
Ephedra · ECA Stack · Ma Huang
A sympathomimetic amine that works through both direct beta-receptor activation and indirect norepinephrine release to increase thermogenesis and metabolic rate. The classic fat burner, often stacked with caffeine and aspirin (ECA stack). The JAMA meta-analysis of ephedra/ephedrine trials shows ~0.9 kg/month weight loss above placebo. Carries significant cardiovascular risks.
Liothyronine · Cytomel · Triiodothyronine
The most biologically active thyroid hormone, roughly 3-4x more potent than T4 at the cellular level. Used in bodybuilding to dramatically accelerate metabolic rate and fat loss during cutting phases. Powerful but carries significant risks including muscle catabolism and thyroid suppression if used improperly.
5 / 10 natty scale / 5
Same lane
Both sit in the same class and are run for cutting, performance. This is a like-for-like comparison: read the gaps as real trade-offs.
The tape
Core ratings
The same three rulers every entry on the site is scored with, read head to head.
Natty scale
1 natural · 10 heavy
Effectiveness
Documented effect · of 5Δ0.5
Side-effect severity
Documented burden · of 5
Cost side
Body-load fingerprint
Where each one actually lands its strain, on the calculator's thirteen channels. Tap a row for what it means and which labs track it.
Cardiometabolic
Organ strain
Hormonal
Systemic
Bars show strain at each one's typical protocol, not your dose. ≈ marks values inferred from side-effect data or category rather than hand-graded. For your numbers, run the calculator.
Logistics
The vitals
Benefit side
What each is for
Shared goals carry both dots; a goal with one dot belongs to that side alone.
Run for
Documented upside
- Meta-analysis (Shekelle et al. 2003, JAMA): ~0.9 kg/month weight loss above placebo (0.6-1.3 kg/month range)
- Increases energy expenditure by 5-10%
- 75% of effect from appetite suppression
- Preserves lean mass during weight loss
- Synergistic with caffeine (ECA stack)
Run for
Documented upside
- Roughly 3-4x more potent than T4 at cellular level
- Rapid onset - effects begin within hours
- Dramatically increases basal metabolic rate
- Enhances fat oxidation and thermogenesis
- Short half-life allows quick adjustment if issues arise
The downsides
Side effects, aligned
Each entry's documented side effects, sorted onto the same body systems so the gaps and the overlaps are visible. Tap any effect for the detail.
None documented
The exit
Hormonal fallout & recovery
What each does to your own hormone axis while on, and what leaving it costs.
Ephedrine
Does not affect HPT axis. No PCT required.
T3 (Cytomel)
T3 does not affect the HPT (testosterone) axis. However, it does suppress the hypothalamic-pituitary-thyroid axis. No traditional PCT needed but MUST taper dose and allow thyroid recovery. Older TRH-stimulation studies of thyroid hormone withdrawal found the pituitary TSH response returning within roughly 1-2 weeks in many patients, with full normalization of the axis taking longer. Exact timelines are dose- and duration-dependent and not tightly established for bodybuilding-style protocols, so treat "2-8 weeks" as the working estimate.
Read-out
How they separate
- 01
Enhancement
They land at almost the same point on the natty scale (5/10 vs 5/10): a similar distance beyond natural.
- 02
Body load
The widest gap at typical protocols is shutdown depth (T3 (Cytomel) 5.6/10 vs 0/10).
- 03
Coming off
Neither requires PCT: both leave the natural testosterone axis running.
- 04
Logistics
typical runs are 4-12 weeks vs 4-8 weeks.
- 05
Tested athletes
Ephedrine is WADA-prohibited; T3 (Cytomel) is not on the prohibited list.
Generated from each entry's data file. Descriptive, not a recommendation; nothing here is medical advice.