Screening & monitoring
Genetic testing to choose diet or supplements (nutrigenomic panels)
Graded on: diet quality and health measures with advice tailored to genotype, compared with personalized advice that does not use genotype.
Grade D, tested: a human randomized trial looked for a benefit on the endpoint The outcome a trial measures to decide whether the treatment worked, such as heart attacks, blood pressure or a symptom score. graded and did not find one. How to read a grade →
Compare this record with another, side by side →
How this letter has changedLatest: October 2026 · Corrected.
Gene-test panels sold to choose diet changes and supplements now have a record. The largest randomized trial of the idea, Food4Me (Celis-Morales et al., Int J Epidemiol, 2017; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 27524815), gave adults in seven European countries personalized nutrition advice with and without their genotype; the genotype added nothing beyond advice based on diet alone. D on Route 2 Human randomized trials have been run and did not show benefit on the stated outcome. One of the two routes to the lowest letter on EBL's scale.. Gene testing to guide medication choice is a different question and is not graded on this record.PMID 27524815
Every change to a letter on this site is dated and published. The full evidence log →
Nutrigenomic tests read your genes to choose a diet or supplements. The largest study of this idea gave people diet advice with or without their gene results. Adding the gene results did not change how much their eating or health improved. So the gene test added nothing beyond good general advice.
A letter describes the human evidence, not the product, the manufacturer, or the intervention's worth.
See the full evidence record →This was not skipped. A human randomized trial has tested it and did not find a benefit on the endpoint below. That is a different statement from an untested intervention, which may still turn out to work. A Route 1 No human randomized trial has been run, so the record rests on animal or mechanistic evidence only. One of the two routes to the lowest letter on EBL's scale. Grade D means nobody has looked. A Route 2 Grade D means somebody looked and the answer was no.
Population Adults in seven European countries; 1,269 completed
Certainty Moderate. One large randomized trial; endpoint is self-reported diet.
PMID 27524815 →
Population 11 studies pooled; adults in the general population or at risk of cardiovascular disease, type 2 diabetes or obesity
Certainty Moderate. Pooled analysis; endpoints are behavior measures, mostly self-reported.
PMID 36779907 →
Graded on Diet quality and health measures with advice tailored to genotype, compared with personalized advice that does not use genotype.
Why this gradeGrade D, tested, no benefit. The reasoning, and what the grade does not cover.
Grade D on Route 2: tested, and no added benefit. The claim these panels rest on is that a gene test tells you in advance which diet changes or supplements will work for you. The largest randomized trial of that idea, Food4Me (PMID 27524815), gave people personalized nutrition advice with and without their genotype, and the genotype added nothing beyond advice based on what they already ate. A meta-analysis A study that pools the numbers from several trials into one combined estimate. of 11 studies of genotype-based advice found no effect on diet or physical activity beyond general advice (King et al., 2023; PMID 36779907). No randomized trial has shown that choosing a supplement by genotype improves a health outcome.
WHAT THIS GRADE DOES NOT COVERgene testing to guide medication choice (pharmacogenomics), which is a different question with its own trial evidence, summarized on the myths page; and diagnostic genetic testing for inherited disease, which is medical care rather than a consumer panel.
A grade describes the human evidence for a named use. It is not advice, and it is not a judgment on any individual prescription. How the letters are decided →
The evidence, in fullTwo papers, each linked to its PubMed record.
Celis-Morales et al. (Int J Epidemiol, 2017; PMID 27524815), the Food4Me trial: adults in seven European countries randomized to standard dietary advice or to personalized advice based on diet alone, on diet plus blood and body measures, or on diet plus those measures plus five diet-related genetic variants, for 6 months; 1,269 completed. Personalized advice improved diet more than standard advice. Adding the blood and body measures or the genotype did not improve it further. King et al. (Nutr Rev, 2023; PMID 36779907): systematic review A review that searches for every study on a question using a method set in advance, then assesses them together. and meta-analysis of 11 studies comparing genotype-based diet or physical activity advice with general advice; no effect on dietary behavior (standardized mean difference 0.00, 95% CI -0.11 to 0.11) or on physical activity (-0.01, 95% CI -0.10 to 0.08). Grade D, Route 2.
Evidence notes: randomized trial
Endpoint graded: Diet quality and health measures with advice tailored to genotype, compared with personalized advice that does not use genotype (self_report)
Last reviewed: October 2026
Educational use only · Not medical advice · EBL grades published human evidence and does not recommend treatment. Stopping a prescription is a decision for your physician.
Primary evidenceTwo papers, each linked to its PubMed record.
Celis-Morales et al. (Int J Epidemiol, 2017; PMID 27524815), the Food4Me trial: adults in seven European countries randomized to standard dietary advice or to personalized advice based on diet alone, on diet plus blood and body measures, or on diet plus those measures plus five diet-related genetic variants, for 6 months; 1,269 completed. Personalized advice improved diet more than standard advice. Adding the blood and body measures or the genotype did not improve it further. King et al. (Nutr Rev, 2023; PMID 36779907): systematic review and meta-analysis of 11 studies comparing genotype-based diet or physical activity advice with general advice; no effect on dietary behavior (standardized mean difference 0.00, 95% CI -0.11 to 0.11) or on physical activity (-0.01, 95% CI -0.10 to 0.08). Grade D, Route 2.
This page carries a letter. EBL takes no commission, referral fee or payment of any kind on anything it grades. No letter has been bought and none is for sale. Products listed under this modality may be commercial partners, and their purchase links may earn EBL a commission. Those products carry no letter of their own, every relationship is disclosed beside the link, and where a product does not deliver what the trials tested, this page says so regardless of who pays.
How this is enforced
That is not a promise, it is a build condition. Two checks run on every deploy: one refuses to publish if a commission is claimed on anything graded, the other refuses if a page names a commercial relationship that is not declared in the register. If either fails, this page does not go live. You can read how the checks work, and what they do not cover, on the evidence integrity page.
Evidence Based Longevity, Inc. is owner-operated and edited by Arnold Sandlow, D.C., a California-licensed chiropractor. Evidence Based Longevity publishes in English only · Machine translations are not produced or reviewed by EBL for accuracy
© Evidence Based Longevity, Inc.. All rights reserved
These statements have not been evaluated by the Food and Drug Administration. Any grade on this page describes the strength of published human trial evidence in the populations studied. It is not a recommendation for any individual and is not medical advice. Starting, stopping or changing any supplement or medication is a decision for your physician.
How EBL searched for the trials (1 search)
The search that was run, what it returned, and what was left out and why, so the absence of evidence can be checked as well as its presence.
(nutrigenomic*[tiab] OR nutrigenetic*[tiab] OR genotype-based[tiab] OR "genetic testing"[tiab] OR "gene-based"[tiab]) AND (diet*[tiab] OR nutrition*[tiab] OR supplement*[tiab]) AND (randomized controlled trial[pt] OR meta-analysis[pt])Grades move when new trials publish. A free monthly email lists every grade EBL moved, with the reason and the trial behind it: the sign-up is on the Evidence Log →