T.J. Dillashaw: natty or not?
Confirmed Two-time UFC bantamweight champion, and an EPO positive that cost him the belt
Short answer. Verdict: confirmed. At the peak physique on this page, T.J. Dillashaw is 5'6" (168 cm) and 134 lbs (61 kg) at roughly 7% body fat. That works out to an FFMI of 20.8, against the ~25 mark cited as the natural ceiling.
The numbers (estimated)
| Peak physique | Bantamweight fighting weight, 135 lbs |
|---|---|
| Height | 5'6" (168 cm) |
| Weight | 134 lbs (61 kg) |
| Body fat | ~7% |
| FFMI | 20.8 — ~25 is the cited natural ceiling |
Era by era (estimated)
| Era | Year | Age | Weight | Evidence | Body fat | FFMI |
|---|---|---|---|---|---|---|
| College wrestling, 133 lb class | 2007 | 21 | 132 lbs (60 kg) | weighed | ~10% | 19.9 |
| Bantamweight title reign | 2018 | 32 | 134 lbs (61 kg) | reported | ~7% | 20.8 |
FFMI over time (estimated)
FFMI per era (values in the table above). Hover a point for details.
Note. Fighting weight is the division limit; the body-fat number is an estimate. The verdict is not — he admitted it. See the methodology page for how we judge.
T.J. Dillashaw’s page is here to make one point that the bodybuilding pages cannot: the drug that ended his title reign does not build a single ounce of muscle.
On 19 January 2019 he tested positive for recombinant human EPO. The New York commission suspended him twelve months; USADA added two years. He gave up the UFC bantamweight title on 20 March 2019. In April he posted an admission — “I messed up” — and said his EPO use was limited to the Cejudo fight.
Confirmed, by test and by his own post.
What EPO does
EPO raises red blood cell count. More red cells carry more oxygen, and more oxygen means a fighter can keep working in round three at a pace that should have emptied him in round one. It shows up nowhere on a physique. Dillashaw fought at 135 lbs and looked exactly like a man who fights at 135 lbs.
Every visual method on this site — FFMI, body-fat reads, rate-of-gain — would have called him clean, correctly, and missed the thing he actually did.
Verdict
Confirmed — a positive test, two sanctioning bodies, a vacated title, and an admission. The cleanest kind of record there is, on a fighter no photograph would have flagged.
In their words
“I messed up”
Common questions
Is T.J. Dillashaw natty or on steroids?
This site rates T.J. Dillashaw as confirmed, the only verdict here stated as fact. It takes an admission, a failed test or an official record, and the one behind this page is cited in the sources below.
Has T.J. Dillashaw ever failed a drug test or admitted to using PEDs?
The record that settles this page is listed in the sources below and described in the article above. It is what makes the verdict confirmed rather than an opinion.
What is T.J. Dillashaw's FFMI?
About 20.8. That comes from 5'6" (168 cm) and 134 lbs (61 kg) at roughly 7% body fat, normalized to 1.8 m. Drug-free lifters in the Kouri 1995 study topped out near 25.