biohacks
Step-by-step longevity protocols — cold exposure, breathwork, light therapy, fasting, sauna — with the research behind each one and how to fit it into a normal day.
CO2 Tolerance Test — Monthly
After a normal exhale, hold and time the first strong urge to inhale: under 20 s low, 20–40 s average, over 40 s high. Track monthly.
Caffeine Cutoff 8 Hours Before Sleep
No caffeine within 8 hours of sleep. Its 5–6 h half-life means an afternoon coffee still occupies adenosine receptors at bedtime.
Bright-Light Box — Winter Mornings
A 10,000-lux light box for 20–30 min within an hour of waking is the best-supported intervention for winter seasonal mood dips.
Hot Bath 40 °C — 90 min Pre-Sleep
A 15-minute 40 °C bath 90 minutes before lights-out raises then drops core temperature, accelerating sleep onset.
Cold Plunge — 3 min at 11 °C
Three minutes to the shoulders in 10–12 °C water, 2–3x/week, triggers a norepinephrine release that sharpens alertness for hours.
CGM-Tracked Meal Experiment
Wear a CGM for 14 days, log each meal, and review which meals spiked glucose. Personalised data beats any generic glycemic-index table.
Box Breath — Daily Vagal Tone
Five minutes of 4-4-4-4 box breathing each morning builds long-term HRV and shifts baseline autonomic balance toward parasympathetic.
Blue-Blocker Glasses — Evening
Amber glasses that block 470–500 nm in the last 90 minutes before bed preserve evening melatonin when room lighting cannot be dimmed.
24-Hour Fast — Monthly
One full 24-hour water-only fast per month, dinner to dinner. Practises metabolic flexibility and gives the digestive system a deeper reset than daily TRE.
Grounding (Earthing): 10 Minutes Barefoot Outdoors
If you spend most of your day indoors, even ten minutes of barefoot outdoor time is a low-cost daily habit. We walk through the protocol, the contraindications, and why grounding evidence is rated 'low'.