STUDresearch · Non-peptide
DIM
Also known as
Diindolylmethane · 3,3'-diindolylmethane · 3,3’-Diindolylmethane · BioResponse DIM · I3C metabolite (discussed) · cruciferous estrogen supplement
Community talk. May contain inaccuracies. Not medical advice. Not a protocol. Not for human or animal use.
Non-peptide
Lots of talk
Systemic
Oral
Hormone modulators
Systemic oral — a capsule with food, not a scalp liquid or an AI pill.
What people say
DIM is 3,3′-diindolylmethane, a crucifer-derived supplement discussed for estrogen-metabolite patterns, acne and TRT-related symptoms. It is not anastrozole, and changing urinary metabolite ratios is not the same as predictably lowering serum estradiol.
Doses people talk about
Rows preserve the original community and trial-adjacent amounts without treating DIM as an aromatase inhibitor, a dose ladder or predictable serum-E2 control. Community amounts are commonly discussed with dietary fat; formulation-specific absorption means crystalline and enhanced BR-DIM products are not equivalent.
How it may feel
Most reports are not acutely dramatic. Inspected accounts range from several-day headache after only two days, to acne improvement emerging around week three or four, to delayed breakouts, migraines or libido changes after stopping; hormone context and concurrent changes remain major confounders.
Lower community daily amount100 mg/day oral
Common TRT and biohacking amount; reports include both no serum-E2 change and adverse or perceived benefit narratives.
Modal community daily band150–200 mg/day oral with food
Most often labeled the standard discussion band, not an official universal dose.
Higher discussion band250–300 mg oral
Appears in higher TRT posts and trial-adjacent copying; headache, GI symptoms and exposure saturation become more relevant.
Every-other-day example300 mg every other day, arithmetic average about 150 mg/day
Informal schedule; averaging milligrams does not make exposure identical to 150 mg each day.
Half-life & effect duration
- Half-life in the body
- BioResponse DIM · oral studyAbout 4.3 hours
- Felt duration people report
- Headache accountNearly 3 days after 2 days of use
- Acne accountImprovement around week 3; clearing by week 4
- After stoppingSome describe symptoms over weeks
Cycles people discuss
DIM discussion is usually daily over an 8–12-week reassessment window rather than a short blast. Some TRT users take oral DIM only around testosterone injection days, but that informal timing is neither injectable DIM nor a validated schedule.
Timing
A small repeated BR-DIM study measured mean parent-DIM half-life at 4.29 hours, with substantial variability. Days-to-weeks changes in acne, symptoms or estrogen metabolites are downstream observations and do not mean parent DIM remains in plasma that long.
Around the dose
Clock: With a meal that has fat.
Stacks
DIM is commonly discussed beside TRT, calcium D-glucarate, boron, zinc or B6. Changes made to testosterone amount or other supplements at the same time make serum and symptom attribution unreliable.
Access talk
OTC supplement, not a 503A peptide.
Labs people mention
Serum estradiol (E2) is what TRT people re-check at 6–12 weeks.
Watch for
It can move E2 both ways in logs — crash and “did nothing” both exist.
Tap a line for the full notes and source context.
Timing context & sources
Half-life in the body
A seven-person repeated-dose BR-DIM study measured a mean parent-DIM plasma half-life of 4.29 hours.
Six men and one woman consumed two BioResponse DIM ‘150 mg’ capsules nightly for one week and a final morning amount; the paper clarifies that each capsule provided 45.3 mg actual DIM. Mean parent half-life was 4.29 ± 2.48 hours.
Very small study of one absorption-enhanced formulation under a crucifer-restricted diet. Label milligrams and actual DIM content differ, and the parent-DIM clock does not represent hydroxylated/conjugated metabolites or symptom duration.
- Vermillion Maier et al. — 3,3′-Diindolylmethane Exhibits Significant Metabolism after Oral Dosing in Humans (opens in a new tab)Seven participants used two nominal 150 mg BioResponse DIM capsules nightly for one week plus a final morning amount; each capsule supplied 45.3 mg actual DIM. Mean parent half-life was 4.29 ± 2.48 hours, with multiple hydroxylated and conjugated metabolites detected.Seven-person formulation-specific study with restricted crucifer intake; parent and metabolite clocks are not interchangeable.
Felt duration people report
Inspected accounts do not establish one felt-duration window: headache persisted for days in one short exposure, acne improvement emerged over three to four weeks in another, and post-stop symptoms were reported over weeks.
A PCOS poster reported nearly three days of headache after two days of DIM. Another using 300 mg/day reported acne improvement beginning around week three and full clearing by week four. A six-month user described new symptoms six weeks after stopping, while a TRT report changed DIM and testosterone dose together.
Unverified products, diagnoses, baseline hormones and co-interventions; delayed symptoms may reflect underlying conditions or treatment changes. These timelines are not measured parent half-life or proof of withdrawal.
- Reddit r/PCOS — DIM for hormonal acne (opens in a new tab)OP and same-author follow-up report 300 mg/day, improvement beginning around week three and full acne clearing around week four, taken at a consistent time.Single unblinded PCOS self-report with unverified supplement and no laboratory or treatment-control attribution.
- Reddit r/PCOS — Experiences with DIM (opens in a new tab)OP reports taking DIM for two days and a headache continuing for almost three days; no later same-author resolution was visible.Single brief self-report without amount, verified product, rechallenge or causal assessment.
- Reddit r/PCOS — Is this withdrawal from DIM? (opens in a new tab)Deleted OP describes six months of use with perceived acne/PMDD improvement and cramps, then breakout, migraines and libido changes by six weeks after stopping; no OP follow-up resolved attribution.Deleted single account with no product verification, hormone data or adjudication; ‘withdrawal’ is the poster’s hypothesis, not an established syndrome.
- Reddit r/Testosterone — DIM significantly reduced my E2 and free testosterone (opens in a new tab)OP reports DIM 200 mg/day while simultaneously reducing weekly testosterone from 98 to 91 mg; estradiol, total and free testosterone all changed, perceived wellbeing improved, and gym strength stalled. Same-author replies did not isolate DIM.Concurrent testosterone change makes causal attribution impossible; self-reported labs, product and timing are not independently verified.
Other context in this card
- Reed et al. — Single-dose pharmacokinetics and tolerability of absorption-enhanced 3,3′-diindolylmethane in healthy subjects (opens in a new tab)Healthy volunteer dose escalation at 50, 100, 150, 200 and 300 mg BR-DIM: exposure rose through 200 mg but not further at 300 mg; mild nausea, headache and vomiting appeared in some at 300 mg.Very small groups, single-dose absorption-enhanced formulation and limited active participants at each amount; not a general supplement dose recommendation.
- Heath et al. — A phase I dose-escalation study of oral BR-DIM in castrate-resistant prostate cancer (opens in a new tab)Cancer trial used oral BR-DIM in twice-daily cohorts and reported first-dose Tmax generally around 2–4 hours; regimen and pharmacokinetics were formulation- and population-specific.Small oncology phase I study, not a wellness or TRT dosing guide and not evidence for generic split-dose instructions.
What people say
- TRT E2 “a little lower”: Logs of E2 30s → 20s on 100 mg, or symptom relief without an AI. Other logs show E2 unchanged or up. forumanecdote
- Crash stories exist: 100 mg nightly for a few weeks then “E2 crashed / back pain / ED” threads — the opposite camp from “DIM does nothing.” anecdote
- Acne / energy n=1s: Biohacker 100–200 mg with meals; confounders (zinc, boron, vitamin D) are loud. forum
- What talk does not prove: Replacing a prescribed AI, fixing gyno, or growing hair. forum
- Women’s metabolite studies: 108 mg/day-class BioResponse work showing 2-OH:16-OH shifts in postmenopausal cohorts. Not a TRT RCT. trial
Doses people talk about
- 100 mg/day: Common TRT/biohack start. Some stay; some say it did nothing to E2. forum
- 150–200 mg/day: The modal “standard” band, with food. forum
- 250–300 mg: Higher TRT posts and some oncology-trial milligrams people copy. Headache/GI talk rises. forumtrial
- EOD 300 mg as a way to average ~150/day. anecdote
- With fat: Fat-soluble lore — empty-stomach DIM is the “why didn’t it do anything” autopsy. forum
- Framing: Supplement milligrams — not a prescription AI. forum
How it may feel
- Days 1–7: Usually nothing dramatic. Occasional headache or GI. forum
- Weeks 1–3: TRT “felt great then shed/ED” or “acne calmed.” anecdote
- Weeks 6–12: The “give it 8 weeks” women’s-hormone calendar. forum
- Urine smell (cabbage/asparagus-class) is a running joke when it is working-as-a-supplement. forum
- After stopping: Some legacy logs say sides ease; other inspected accounts describe delayed breakouts, headaches or libido changes over days to weeks. One six-month user stopped because of daily cramps during use, then reported different symptoms about six weeks later. Diet, body fat, TRT dose and underlying conditions confound attribution; this does not establish withdrawal. forum
Around the dose
- Clock: With a meal that has fat. forum
- TRT day: Some only take it the day after a pin. forum
- Not pre-workout. forum
Cycles people discuss
- Daily while the hormone experiment is on — not an 8-week SARM blast. forum
- 8–12 weeks then re-lab is the TRT advice-column rhythm. forum
- Around TRT injection days: Legacy discussion includes oral DIM only near testosterone injection days when 200 mg capsules feel like too much; DIM itself is not injected, and the informal schedule is not validated. forum
Timing
- Divided schedules in discussion: Legacy label-style posts discuss splitting amounts above 200 mg between AM and PM with meals. This is not a general dosing instruction or an inference from parent half-life. Separate BR-DIM oncology studies used twice-daily schedules in specific clinical populations. forumtrial
- Labs, not vibes: Serum E2 vs urinary 2:16 ratio are different questions — forums mix them. forum
- Parent versus downstream timing: A seven-person repeated BR-DIM study measured mean parent-DIM half-life of 4.29 ± 2.48 hours; metabolite ratios and symptoms are separate endpoints. trial
More on what it is
- What most people mean: The “eat broccoli in a pill to move estrogen” supplement on TRT and biohacker boards. Not Arimidex. forum
- Why people search it: r/trt wants a gentler E2 tool than anastrozole; women’s boards want “estrogen dominance,” acne, PMS. Hair people borrow it. forum
- How discussion frames mechanism: Shift urinary estrogen metabolites toward 2-OH vs 16-OH — a ratio story, not a guaranteed crash of serum estradiol. trialforum
- BioResponse vs crystalline: Enhanced/microencapsulated 100–200 mg is the trial-ish band; cheap crystalline often gets doubled in forum math. forum
- Not: Not anastrozole, not DIM the peptide, not I3C itself, not a SARM. forum
- What it is: 3,3′-diindolylmethane, a digestion product of indole-3-carbinol from crucifers. Supplement milligrams dwarf a serving of broccoli. trial
Stacks
- Solo 100 mg to see if E2 symptoms or acne move. forum
- + Calcium D-glucarate: Phase II “keep the metabolites moving” add-on. forum
- + Boron / zinc / B6: Biohacker hormone drawer. forum
- + TRT: The r/trt context — DIM as AI-lite. forum
- + Sulforaphane / I3C: Cruciferous pile-on. forum
Access talk
- OTC supplement, not a 503A peptide. forum
- BioResponse vs generic crystalline is the absorption fight, not compounding law. forum
Labs people mention
- Serum estradiol (E2) is what TRT people re-check at 6–12 weeks. forum
- Do not skip the TRT panel (T, E2, HCT, PSA as discussed) and blame DIM for the whole axis. forum
- Urinary 2-OH:16-OH is the women’s-metabolite story — a different lab than serum E2. trial
Storage notes
- Capsules. Room temp, dry. forum
- Not a peptide vial. forum
Watch for
- It can move E2 both ways in logs — crash and “did nothing” both exist. forum
- Headache / GI at 200–300 mg. forum
- Acne flare in a minority (including TRT users). anecdote
- Hair shed in people who already shed on AIs. anecdote
- Not a replacement AI for high-dose testosterone. forum
- Women pregnant / trying: Hormone-metabolite supplement — forums say skip. forum
Evidence mix
Mostly community / anecdote tags
Full: every bullet (trial + community). Use Scan for a faster bro-science read.