Ordinary foods with unusual chemistry: chopping or chewing releases sulfur compounds that switch on the body's own defensive enzymes. The strongest human findings are small improvements in blood sugar control and a fall in blood pressure over two weeks. Drawbacks: digestive discomfort at large portions, some medicines wearing off faster. Lifespan extension shown only in animals. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Thyroid-stimulating hormone | 0.5–2.0 mIU/L | Detects the one documented thyroid effect |
| Free thyroxine | 1.0–1.5 ng/dL | Confirms a real hormone shortfall |
| Urinary iodine concentration | 100–199 µg/L | Identifies when thyroid risk is real |
| Glycated haemoglobin (HbA1c) | 4.8–5.4% | Tracks the best-evidenced metabolic benefit |
| Fasting glucose | 75–86 mg/dL | Primary endpoint in the glucose trials |
| Home systolic blood pressure | Below 120 mmHg | The only clinical endpoint moved in a trial |
| High-sensitivity C-reactive protein | Below 1.0 mg/L | General inflammation marker |
| Alanine aminotransferase (ALT) | Below 25 U/L (men), below 20 U/L (women) | Tracks the liver benefit |
| International normalised ratio (INR) | Own prescribed target, typically 2.0–3.0 | Detects destabilised anticoagulation |
| Urinary isothiocyanate excretion | None established; change from own baseline | Confirms conversion and absorption |
Cadence: Blood pressure at 2 and 4 weeks, then quarterly. HbA1c and liver panel at 3 and 6 months, then 6–12 monthly. Thyroid at 3 months and annually where iodine is low or raw intake high. INR 1–2 weeks after a sustained change.