Evidence
Sources behind every “What helps” lever.
The topic guides on your results page are short on purpose. Every claim ties to a primary source listed here. We prefer NIH ODS, NCCIH, USPSTF, AAFP, ESC, BMJ, JAMA, PubMed/PMC, and major guideline bodies. Each reference shows the date we last re-checked the link.
Nutrient gaps — what helps
Self-reported signs of low nutrient status are useful but never enough on their own. Confirm with a lab where you can, fix the food side before adding a capsule, and review again in 8–12 weeks.
Stress — what helps
Movement, daylight, and protected sleep do more for nervous-system load than almost any supplement. Use the supplement layer for the gaps these leave, not as a replacement.
Blood sugar — what helps
Three behavioural levers move post-meal glucose more than any supplement: what you eat, what order you eat it in, and what you do after. Apply them daily; supplements are a distant fourth lever.
- Buffey et al. 2022 — short post-prandial walks lower glucose, meta-analysis
- Shukla et al. 2017 — vegetable/protein-first meal ordering lowers post-meal glucose
- USPSTF 2021 — screening for prediabetes and type 2 diabetes in adults
- Lane et al. 2024 — ultra-processed food exposure & multiple health outcomes, BMJ umbrella review
- Irish et al. 2015 — sleep hygiene practices and outcomes, systematic review
Sleep & circadian — what helps
For chronic sleep complaints, behavioural therapy (CBT-I) is first-line and outperforms hypnotics over the long term. Most adults can do 70% of the work themselves with these levers.
- AASM 2017 — clinical practice guideline for chronic insomnia (behavioural therapies first-line)
- Irish et al. 2015 — sleep hygiene practices and outcomes, systematic review
- Chang et al. 2015 — evening light exposure shifts circadian rhythms & impairs sleep
- Drake et al. 2013 — caffeine effects on sleep taken 0, 3, or 6 hours before bed
Lifestyle risk — what helps
Alcohol, smoking, and low produce intake have the largest single effects of anything on this site. Working on them is more important than any supplement decision.
- GBD 2018 (Lancet) — alcohol use and burden, no safe level for overall health
- USPSTF 2021 — interventions for tobacco smoking cessation in adults
- Aune et al. 2017 — fruit/vegetable intake & mortality, meta-analysis of 95 cohorts
- Singh et al. 2023 — physical activity for depression, anxiety, distress, umbrella review