Match the purpose
Creatine has a clearer role in repeated high-intensity performance than in claims about lifespan.
THE CONNECTIONS / 06
Evidence for what—and for whom?
Start with an outcome and a population. Muscle performance, deficiency correction and anti-aging marketing are different questions.
Original conceptual model
The claimWhat is it for?
PopulationWho was studied?
EvidenceWhich outcome?
SafetyRisks / interactions
NeedIs it relevant?
View the full-width diagram
Swipe horizontally to explore the diagram at its original size.
Read diagram relationships
- The claim — What is it for?
- Population — Who was studied?
- Evidence — Which outcome?
- Safety — Risks / interactions
- Need — Is it relevant?
Start with these distinctions
Baseline changes the question
Treating a deficiency differs from adding a nutrient to a generally well-nourished population.
Read negative and uncertain results
Large trials can miss hoped-for benefits; small positive biomarker trials still leave major questions open.
A way to investigate
Purpose
Name the outcome before choosing an ingredient.
Evidence
Find a relevant population, comparator and outcome.
Context
Check limitations, interactions and whether professional assessment is needed.
THE PEOPLE
Voices exploring this subject
Biomedical scientist · FoundMyFitness
Rhonda Patrick
Follow the pathway from nutrient to evidence.
Neuroscientist · Huberman Lab
Andrew Huberman
Understand the mechanism. Examine the protocol.
Entrepreneur · Blueprint
Bryan Johnson
A public experiment in measuring aging.
UPSTREAM
Research sources
NIH ODS: Dietary Supplements for Exercise and Athletic Performance—Health Professional Fact Sheet
Creatine can support repeated high-intensity effort; adequate protein supports muscle repair and training adaptation.
Original sourceLiving source
A Systematic Review, Meta-analysis and Meta-regression of the Effect of Protein Supplementation on Resistance Training-induced Gains in Muscle Mass and Strength in Healthy Adults
Protein supplementation added modest gains in muscle size and strength during resistance training.
Original source2018
NIH ODS: Vitamin D—Health Professional Fact Sheet
Vitamin D supports calcium absorption and bone physiology; deficiency and excess both matter.
Original sourceLiving source
Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease
Vitamin D did not significantly reduce the primary outcomes of invasive cancer or major cardiovascular events.
Original source2019
Supplemental Vitamin D and Incident Fractures in Midlife and Older Adults
Supplemental vitamin D did not significantly lower total, nonvertebral or hip fracture risk.
Original source2022
NIH ODS: Omega-3 Fatty Acids—Health Professional Fact Sheet
EPA and DHA have physiological roles; triglyceride treatment and general prevention are different questions.
Original sourceLiving source
Marine n−3 Fatty Acids and Prevention of Cardiovascular Disease and Cancer
Marine omega-3 did not significantly reduce the primary composite cardiovascular outcome or invasive cancer.
Original source2019
NIH ODS: Magnesium—Health Professional Fact Sheet
Magnesium supports many enzyme systems; food sources include legumes, nuts, whole grains and leafy vegetables.
Original sourceLiving source
Oral Magnesium Supplementation for Insomnia in Older Adults: A Systematic Review & Meta-analysis
Pooled trials suggested shorter sleep-onset time, with uncertain effects on total sleep time.
Original source2021
Nicotinamide Mononucleotide Increases Muscle Insulin Sensitivity in Prediabetic Women
NMN improved muscle insulin sensitivity; several other metabolic measures did not change.
Original source2021
Chronic Nicotinamide Riboside Supplementation Is Well-tolerated and Elevates NAD+ in Healthy Middle-aged and Older Adults
NR increased NAD-related measures and was tolerated during this short trial.
Original source2018
RESEARCH & LEARNING
Take the question further
Audit a supplement stack by ingredient, serving and unit
Three different bottles can contain the same nutrient. Work through invented vitamin D and magnesium labels to separate arithmetic, reference values and the decision about whether a product is useful.
5 source recordsRead the lesson
Supplement interactions: absorption, drug effects and laboratory tests
Use vitamin K, magnesium, St. John’s wort and biotin to distinguish several mechanisms. Learn what information makes a pharmacist’s review possible without turning the examples into a self-directed medicine schedule.
6 source recordsRead the lesson
Why do probiotic results depend on the strain and the problem?
A probiotic is not one uniform ingredient. Learn to identify the organism, formulation and clinical purpose.
3 source recordsRead the lesson