Sulforaphane for Health & Longevity - Quick Reference Sheet

Sulforaphane for Health & Longevity

Created on 08/13/2026 – Quick Reference based on Evidence Review created using AI4L / Opus 5 – Audit

Formed when broccoli and related vegetables are crushed or chewed, it raises the activity of the body's own protective and waste-removal systems. The best-repeated human effect is faster removal of inhaled and dietary pollutants. Smaller, less certain signals: blood sugar, mental speed and mood in older adults, cell division. Digestive upset is common; much research carries commercial ties. (Full Review)

Protocol

Standard supplement dose
20–30 mg daily
Sulforaphane equivalent, roughly 110–170 µmol, taken with a meal
Best time of day
Morning with breakfast
Once-daily dosing was used in every efficacy trial; keeps peak levels away from sleep
Preparation determines yield
Mustard seed powder
Myrosinase is destroyed above roughly 70 °C; added active myrosinase restores conversion
Time to effect
Carcinogen excretion
Within days
Nothing subjective is likely to be noticeable early
Metabolic and liver endpoints
12–24 weeks
Fasting glucose where control is already impaired; ALT at 24 weeks
Cognitive change
12 weeks
Processing speed and negative mood in adults over 60

Benefits

Contraindications
  • Pregnancy (any trimester) and breastfeeding
  • Documented iodine deficiency (spot urinary iodine below 100 µg/L)
  • Active cytotoxic chemotherapy or radiotherapy (unless reviewed by the treating oncologist)
  • Known allergy to Brassica species
  • Within 7 days of scheduled surgery when the source is whole sprouts
Key Interactions
  • Anticoagulants (warfarin)
  • CYP1A2 substrates (caffeine, theophylline, clozapine, olanzapine)
  • Acetaminophen and other glutathione-depleting agents
  • Glucose-lowering agents (metformin, insulin, glipizide)
  • Thyroid hormone replacement (levothyroxine)
  • Other supplements (N-acetylcysteine, alpha-lipoic acid, curcumin, resveratrol)
  • High-dose antioxidant supplementation around training

Risk & Side Effects

  • High: Gastrointestinal intolerance
  • Medium: Sleep disruption and irritability at higher doses
  • Low: Altered clearance of CYP1A2-metabolized drugs from whole-crucifer sources; thyroid function changes under iodine insufficiency; fetal and breast milk exposure
  • Speculative: Blunting of exercise-induced adaptation; cytoprotection of established NRF2-overactive tumors

Monitoring

Marker Target Why
TSH 0.5–2.0 mIU/L Detects the historical goitrogenic concern
Free T4 1.0–1.5 ng/dL Confirms thyroid output independent of pituitary signaling
TPO antibodies Negative, below 9 IU/mL Identifies autoimmune thyroid disease, the subgroup with least safety data
Spot urinary iodine 100–199 µg/L Determines whether the goitrogenic concern applies at all
Fasting glucose 75–86 mg/dL Primary metabolic endpoint in the sulforaphane trials
HbA1c 4.8–5.3% Averages blood sugar over about three months, smoothing daily noise
ALT 10–26 U/L in men, 10–19 U/L in women The one liver marker moved in a controlled trial
GGT Below 20 U/L in men, below 15 U/L in women Tracks liver oxidative stress and glutathione turnover, the pathway sulforaphane acts on
hs-CRP Below 0.5 mg/L General inflammation marker; sulforaphane trials have mostly failed to move it
GSTM1/GSTT1 genotype No established target; genotype is fixed — track the response to a fixed dose instead Indicates how fast sulforaphane is conjugated and cleared

Cadence: Baseline, then thyroid and liver panels at 12 weeks, 6 and 12 months, and annually thereafter if stable; metabolic markers at 12 weeks and 6 months. TPO antibodies and genotype once at baseline.

Qualitative Assessment

  • Digestive tolerance: gas, bloating, belching, and nausea in the first two weeks, which should settle as the dose stabilizes
  • Sleep onset and continuity, particularly in the first month and after any dose increase
  • Daytime mental sharpness and speed of routine tasks, the domain in which the older-adult trials found change
  • Mood, tracked against the individual's own baseline rather than a scale
  • Sulfurous taste aversion or breath odor, the most common reason people abandon whole-sprout approaches