Overview
YouBoost rates interventions using a three-tier evidence system (A, B, C) based on the quality and consistency of available research. This page explains our criteria in detail.
Our goal is to give you an honest assessment of what we actually know, not what we hope or assume. A lower rating doesn't mean something is worthless, it means the evidence isn't strong enough to be confident.
Evidence Rating Criteria
A Rating (Strong Evidence)
An intervention receives an A rating when:
- Multiple well-designed randomized controlled trials (RCTs) show consistent positive effects
- Meta-analyses or systematic reviews confirm the effect across studies
- Effect sizes are clinically meaningful, not just statistically significant
- Results have been replicated by independent research groups
- The intervention has a well-understood mechanism of action
Examples: Creatine for strength, caffeine for alertness, melatonin for sleep onset
B Rating (Moderate Evidence)
An intervention receives a B rating when:
- At least one well-designed RCT shows positive effects, OR
- Multiple observational studies show consistent associations with plausible mechanisms
- Effect sizes are meaningful but may be modest
- Results are promising but need more replication
- Some limitations exist (small sample sizes, short duration, or specific populations)
Examples: Cold exposure for recovery, time-restricted eating for metabolic health
C Rating (Preliminary Evidence)
An intervention receives a C rating when:
- Only preliminary human studies exist (pilot studies, small trials)
- Evidence is primarily from animal or cell studies with limited human data
- Human studies show mixed or inconsistent results
- Mechanisms are plausible but unproven in humans
- The intervention is popular but lacks rigorous research
Examples: Nootropics like lion's mane, many adaptogens, emerging biohacks
What We Consider
Study Quality Factors
- Study design - RCTs weighted higher than observational studies
- Sample size - Larger studies are more reliable
- Duration - Longer studies capture effects that short studies miss
- Blinding - Double-blind, placebo-controlled studies reduce bias
- Publication source - Peer-reviewed journals vs. preprints or company-funded reports
- Conflict of interest - Industry-funded studies are noted but not excluded
Outcome Factors
- Clinical relevance - Does the measured outcome matter in real life?
- Effect size - How large is the benefit?
- Consistency - Do multiple studies show similar results?
- Generalizability - Does it work across different populations?
What We Don't Do
- Cherry-pick studies - We consider the body of evidence, not just favorable papers
- Rate based on popularity - Viral trends don't influence our ratings
- Assume mechanisms prove efficacy - A plausible mechanism doesn't mean it works
- Ignore negative studies - Null results are part of the picture
- Accept testimonials as evidence - Personal stories aren't data
Sources
Our primary sources include:
- PubMed/MEDLINE - The standard database for biomedical literature
- Cochrane Reviews - High-quality systematic reviews
- Meta-analyses - Quantitative synthesis of multiple studies
- Peer-reviewed journals - Original research from reputable publications
We cite specific studies on each intervention page and link to the original sources when available.
Limitations
Every rating system has limitations:
- Research gaps - Some interventions lack funding for large trials
- Publication bias - Negative studies are less likely to be published
- Population specificity - Most studies are done on specific groups (often young, healthy men)
- Individual variation - What works on average may not work for you
- Evolving science - New research can change our understanding
We aim to be transparent about uncertainty. When evidence is mixed or limited, we say so.
Updates and Revisions
Evidence ratings are not permanent. We update them when:
- Significant new research is published
- Meta-analyses change the overall picture
- We receive credible feedback pointing to studies we missed
If you believe we've overlooked important research, reach out via our contact page.