Start here
A short orientation to The Biohacking Bible — what we are, how to read the pages, and where to begin if you've never used the site before.
What we cover, in one paragraph
Ten topics that show up repeatedly in self-experimentation and longevity research: sleep optimisation, continuous glucose monitoring, fasting protocols, cold and heat exposure, heart-rate variability, sauna, nootropics, light therapy, supplements, and consumer wearables. For each topic, we summarise what the published human research reports — not what supplement-shop blogs claim, and not what mouse studies suggest might happen in mammals.
How to read an evidence grade
Every protocol page carries a single-letter grade based on the strength of the human evidence:
- A — multiple high-quality human RCTs, consistent direction.
- B — some human RCTs or large cohort data, mixed but trending.
- C — plausible mechanism, mostly observational or small studies.
- D — animal, in-vitro, or anecdotal; insufficient human evidence.
The grade is about the strength of evidence, not whether you should try the protocol. A grade-A protocol can still be inappropriate for you because of your conditions or medications. A grade-D protocol can still be perfectly safe and harmless to try. The grade is the start of a conversation, not the end of one.
How to read "Last reviewed"
Every page shows the date we last verified its sources and confirmed nothing material had changed. We review pages at least annually, sooner when the MHRA, NHS, or NICE updates relevant guidance.
If you only have ten minutes
Read one of the grade-A protocols below. They are the parts of the biohacking and longevity space where the underlying evidence is strongest.
Glycemic index vs glycemic load: why GI alone misleads
The glycemic index has been on food packaging for decades but tells you only half the story. Glycemic load accounts for portion size and is the more practical metric — though both are limited by individual variability.
cgm · Grade A · 3 min read
Post-meal walks: the evidence behind a 10-minute habit
A short walk after eating is one of the better-studied lifestyle nudges for postprandial glucose. Here's the size of the effect, where the studies were done, and the practical takeaway.
cgm · Grade A · 2 min read
Stress, sleep, and glucose: the overnight insulin resistance signature
Bad sleep produces measurable next-day insulin resistance. Chronic stress amplifies cortisol-driven gluconeogenesis. A CGM makes both visible faster than most people expect.
cgm · Grade A · 3 min read
What a continuous glucose monitor actually measures
A continuous glucose monitor reads interstitial fluid glucose every few minutes. Here's what that means, the lag from blood glucose, and the calibration limits you should know.
cgm · Grade A · 2 min read
Exercise for depression: the trial evidence is strong
Exercise is NICE-recommended for mild and moderate depression with effect sizes comparable to first-line pharmacotherapy in trial data. What the dose looks like, which modalities work, and when exercise isn't enough.
exercise · Grade A · 4 min read
HIIT overview: what it is, what it isn't, and why it works
High-intensity interval training has accumulated substantial evidence for cardiorespiratory and metabolic benefits. What 'HIIT' actually means, the dose, the recovery cost, and where it fits alongside aerobic base.
exercise · Grade A · 4 min read
If you want the full map
The ten sections, with the number of protocols in each:
- Sleep optimisation (13) — Hygiene basics, sleep stages, light/temperature/timing, tracking metrics — what the literature actually supports.
- CGM & glucose (11) — What a continuous glucose monitor measures, what spikes mean in healthy people, meal-order and walking research.
- Fasting protocols (10) — 16:8 overview, autophagy research, electrolytes, women's hormone considerations, refeeds.
- Cold & heat exposure (7) — Cold-water immersion literature, contrast therapy, sauna+cold combinations, beginner ramp-up.
- HRV (7) — What heart-rate variability measures, RMSSD vs SDNN, HRV-guided training studies, breathwork.
- Sauna (6) — Finnish cardiovascular cohort data, infrared vs traditional, frequency and duration evidence.
- Nootropics (10) — Caffeine + L-theanine, creatine and cognition, rhodiola research, an MHRA-cautious overview.
- Light therapy (6) — Morning sunlight and circadian rhythm, red-light research, SAD lamps.
- Supplements (13) — Vitamin D under NHS guidance, omega-3 research, magnesium forms, MHRA Yellow Card framing.
- Wearables (7) — Oura vs Whoop vs Eight Sleep, and the accuracy of consumer wearables versus lab references.
- Exercise (10) — Zone 2 cardio, VO2 max, resistance training for longevity, walking research, grip strength as a biomarker.
- Longevity (11) — NAD precursors, rapamycin and metformin research, spermidine, hormesis as a unifying concept.
A reminder before you act on anything
This is an educational site, not a clinic. The protocols we describe are summaries of research, not recommendations for your body. Talk to a UK-registered clinician before changing anything that matters to your health, and read our medical disclaimer.