Master Guide and Site Index

By Dr. Frank Yap, MD | Medically reviewed by One Day MD Review Team | Last updated: September 29, 2026

Quick Answer: One Day MD is an independent, evidence-based health library covering supplements, longevity, GLP-1 and weight management, cancer prevention, heart and metabolic health, brain and sleep, immunity, skin, joints, family health and finding a specialist. Use this page as your map: check the date, pick a pillar, then narrow by label.

Disclosure: Some pages link to products or partners, and we may earn a commission at no cost to you. This is educational content, not medical advice.

In This Guide

  1. How to Use This Site
  2. Topic Index (12 pillars)
  3. Site Tools and Sister Sites
  4. AI Personalization Guide
  5. FAQ

How to Use This Site

1Check the date: Look for the Last updated line. 2026 guides use current evidence; older posts may not.
2Pick a pillar: Match your question to one of the 12 pillars below and read its flagship guides first.
3Narrow by label: Labels list every post on a topic. Similar labels overlap (for example diet, diet & nutrition, diet & lifestyle), so try neighbours.
4Weigh the evidence tier: Guides separate randomized-trial evidence from observational, mechanistic and anecdotal claims. Treat lower tiers as hypotheses, not proof.

Topic Index: 12 Pillars

Vitamins, Minerals & Supplements

Start here for what the evidence supports (and doesn't) for vitamins, minerals, antioxidants and popular supplements.

Start with:

Browse by label: All supplements · antioxidants · vitamin D · vitamin C · magnesium · zinc · Omega-3 · probiotics · quercetin

Anti-Aging & Longevity

Healthspan science: lifestyle, NAD+ precursors, fasting, mitochondria and emerging anti-aging interventions.

Start with:

Browse by label: Anti-aging · NAD+ · NMN · mitochondrial health · hydrogen water · exercise · intermittent fasting

Weight Loss, GLP-1 & Peptides

GLP-1 medications, body composition, peptides and the evidence behind weight-management claims.

Start with:

Browse by label: weight loss · keto diet · protein · Diabetes

Diet, Nutrition & Nutrigenomics

How food, dietary patterns and your genes interact, from Mediterranean-style eating to personalized nutrition.

Start with:

Browse by label: diet · diet & nutrition · diet & lifestyle · nutrition · nutrigenomics · olive oil

Cancer Prevention & Integrative Oncology

Prevention, screening, biomarkers and evidence-tiered coverage of integrative approaches, hosted with our Cancer Advisor sister site.

Start with:

Browse by label: cancer · pancreatic cancer · immunotherapy · breast cancer

Heart, Blood Sugar & Metabolic Health

Cardiovascular and metabolic risk, from cholesterol and blood pressure to diabetes prevention.

Browse by label: heart health · Diabetes · cardiologists · stroke · health screening

Brain, Sleep & Mental Health

Memory, dementia risk, sleep quality and sleep apnea, plus mood and mental health.

Start with:

Browse by label: brain health · alzheimer · dementia · insomnia · sleep apnea · CPAP · mental health

Immune System, Infection & COVID-19

Immune health, autoimmunity, allergies and the network's long-running coronavirus archive.

Start with:

Browse by label: coronavirus · immune system · autoimmune · allergies

Skin, Hair & Aesthetics

Evidence-based skin care, hair loss and cosmetic procedures.

Start with:

Browse by label: skin health · skincare · acne · hair loss · Botox · laser treatment · aesthetic clinics

Joints, Bones & Pain

Knee pain, osteoarthritis, back pain and joint-health strategies.

Browse by label: knee pain · knee osteoarthritis · joint health · back pain · calcium

Women's Health, Pregnancy & Parenting

Menopause, hormone therapy, pregnancy and baby and child health.

Browse by label: menopause · Hormone therapy · pregnancy · baby · parenting

Find a Specialist, Insurance & Screening

Directories and practical guides for finding the right doctor and understanding coverage.

Start with:

Browse by label: Medical Specialists (US) · Medical Insurance · health screening

Site Tools and Sister Sites

AI Personalization Guide

Use an AI assistant to tailor any guide to your situation. Always verify against the source article and your clinician.

AssistantExample prompt
ClaudePaste a pillar's title and say: 'Summarize the strongest-evidence guides here for a 55-year-old with hypertension, and list questions for my doctor.'
ChatGPTAsk: 'Using One Day MD's longevity pillar, compare fasting-mimicking and molecular-hydrogen evidence, and flag anything preclinical.'
GeminiAsk: 'Read the linked guide and turn it into a one-page checklist I can bring to an appointment.'
PerplexityAsk: 'What newer trials since September 2026 update the claims in this One Day MD guide?' and check its citations.

FAQ

Where should a new reader start?

Read the Quick Answer and the four-step reading path above, then open the pillar that matches your question. Each pillar lists flagship guides first and topic labels second.

How current is the content?

Articles updated in 2026 carry a Last updated date near the top. Older posts, some from 2012, may reflect earlier evidence, so check the date before acting on any recommendation.

Is this medical advice?

No. One Day MD publishes educational, evidence-based information. Discuss diagnosis, medication and supplement decisions with a licensed clinician.

How do I find a doctor?

Use the Find a Medical Specialist guide and the US specialist label listed in the final pillar.

Medical disclaimer: This site provides general education and does not replace professional medical advice, diagnosis or treatment.

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