The Absurdities Collection: How to Evaluate Health Claims About Detoxes, Folk Remedies, and Dietary Supplements

The Absurdities Collection: Where the Evidence Draws the Line on Health Claims

In one sentence

The most common flaw in health claims is the leap from a real ingredient or physiological phenomenon to a therapeutic effect that has not been demonstrated in human trials. A credible judgment must assess the mechanism, clinical outcomes, and scope of the claim together. PMID: 25522674

“It contains a certain ingredient” does not mean “using it this way can treat disease”

Onion extracts can exhibit antimicrobial activity in vitro. That does not mean putting a cut onion in a sock and placing it against the sole allows active compounds to pass through the skin into the bloodstream, much less that it can treat a cold, fever, earache, toothache, or bladder infection. Such claims substitute “direct contact in a laboratory” with “ordinary use can treat disease,” while omitting evidence about human absorption, effective dosage, and clinical efficacy. PMID: 41790658

No clinical trials supporting the onion-in-a-sock remedy can currently be found. This means its efficacy has not been established; the mere absence of a study does not prove that it is categorically ineffective. Professor Lin regards such messages as health claims without a scientific foundation, and the available literature has not overturned his skepticism. PMID: 42256445

Similarly, the presence of nerve endings in the soles does not mean that the feet contain “gateways” to particular internal organs. Nor does it justify inferring that applying something to, or stimulating, a specific area can treat disease in those organs. Systematic reviews have not established that reflexology treats medical conditions. A foot massage may feel relaxing, but that experience does not validate the broader theory of organ reflex zones. PMID: 19740047

“Detox” is not an all-purpose term that can be applied at will

The human body does have systems that process, metabolize, and eliminate foreign substances. Commercial detox diets, detox teas, colon cleansing, and claims that foods of a certain color or flavor can “detoxify” a specific organ must nevertheless identify, in each case, a testable toxin, a biological pathway, and a measurable human outcome. A critical review found the clinical evidence for commercial detox diets to be very weak, with no convincing evidence that specific detox diets eliminate toxins. PMID: 25522674

Claims that winter melon removes “kidney toxins,” radish removes “lung toxins,” green foods detoxify the liver, or toxin-removing tears make women live longer therefore do not become causal explanations merely because the story sounds coherent. Research on emotional tears examines their psychological and social functions; there is no evidence that tears eliminate bodily toxins and thereby produce differences in longevity. PMID: 30854025

“Detox” is not necessarily safe, either. Detox products may cause liver injury, electrolyte disturbances, or other adverse health events, and colon cleansing also carries known risks. When symptoms are present, the cause should be investigated instead of replacing diagnosis with a vague idea of “toxin accumulation.” PMID: 42039908

Skipping dinner is not a “fasting cure-all”

Research on planned eating windows cannot be rewritten as evidence that “skipping dinner treats all kinds of diseases.” Existing studies discuss, at most, how particular eating schedules may affect body weight or metabolic markers. They do not support the boundless claim that hunger cures every illness. A large cohort study instead found that regularly skipping dinner was associated with weight gain, overweight, and obesity. Observational studies still require caution about reverse causation, however, and an association should not be described as an inevitable causal relationship. PMID: 33477859

Skipping dinner is especially inappropriate as a health prescription for adolescents. A systematic synthesis found meal skipping among adolescents to be associated with multiple adverse physical and mental health outcomes. Professor Lin’s opposition to withholding dinner from children is therefore consistent with the direction of the current literature. PMID: 40221786

When confronting extreme denial, return to the evidence for the disease and its treatment

The claim that “HIV does not cause AIDS” is a form of denialism that has been refuted. Professor Lin’s rejection of this claim accords with the literature on causation and treatment. PMID: 39395068

The statement that “drugs, chemotherapy, and radiotherapy cannot truly treat cancer” likewise treats a complex group of diseases as though it were one uniform condition. Cancer is not a single disease; outcomes vary by cancer type, stage, and treatment combination. Systematic evidence shows that chemotherapy and radiotherapy improve survival in some cancers and, in certain circumstances, can achieve a functional cure. PMID: 42294290

The claim that “milk prevents children’s brain development” is also unsupported. The direction observed in a randomized trial was the opposite: milk supplementation improved children’s neurocognitive development. This does not mean everyone must drink milk. It means an individual dietary choice should not be exaggerated into a universal threat to brain development. PMID: 41978217

Digestion breaks down proteins, but the mechanism does not justify an absolute conclusion

Professor Lin has explained that intact proteins are exposed to stomach acid and proteases after entering the digestive tract. This general biochemical principle is sound and helps explain why intact EGF-like proteins are unstable after oral administration and have very low systemic availability. Nor is there reliable clinical evidence that oral EGF provides cosmetic benefits. PMID: 41939723

Scientific advances, however, require a more precise restatement of the proposition that “anything digested must have no effect whatsoever.” Subsequent human studies have detected collagen-derived small peptides that enter the bloodstream after collagen ingestion and retain biological activity. The breakdown of large molecules and the absorption of some small peptides are therefore not contradictory. PMID: 35662250

Subsequent randomized trials and meta-analyses of orally administered hydrolyzed collagen indicate that measurable improvements in skin hydration, elasticity, and wrinkles may occur. The literature has been updated; this should not be portrayed as Professor Lin himself changing what he originally said. A more accurate conclusion is that the digestive principle underlying his earlier statement remains valid, while the inference that oral collagen “must be completely ineffective” should be tempered in light of today’s clinical evidence. PMID: 38192916

For edible bird’s nest, the “specific mechanism” must likewise be distinguished from the “product as a whole.” There is insufficient mechanistic evidence for the claim that edible bird’s nest improves appearance through EGF. Yet a subsequent small human trial observed a slight improvement in wrinkles with the complete edible bird’s nest extract. Rejecting the EGF mechanism cannot be expanded into proof that every edible bird’s nest product is ineffective. PMID: 35355724

Genes, papaya leaf, and supplements: conclusions should match the strength of the evidence

DNA in food is broken down during digestion. Current evidence does not support the idea that eating genetically modified food integrates foreign genes into the human genome, nor does it show a consistent causal relationship with cancer. Professor Lin’s rejection of claims about “replenishing genes” and “genetically modified DNA changing human genes” is aligned with the direction of the literature. PMID: 41772782

The use of papaya leaf for dengue should be described by saying that “the literature has been updated.” Although a subsequent meta-analysis observed low-quality signals involving platelet counts and length of hospital stay, the evidence remains insufficient to establish a therapeutic role. A newer systematic assessment also did not support recommending any single therapy. Papaya leaf should therefore not be described as a proven treatment for dengue, but neither should “unresolved” be rewritten as “proven to have no effect whatsoever.” PMID: 31601215

For papaya-leaf water as a treatment for nocturnal enuresis, urinary incontinence, edema, or memory problems, the literature available for this review was insufficient either to support or refute the claims; they should be clearly marked as “insufficient evidence.” Likewise, broad marketing claims that small peptides can raise basal metabolism, protect DNA, or slow aging should not be treated as facts in the absence of direct human trials.

Supplements should not be presumed safe merely because they are labeled natural. Conversely, one cannot claim that all protein or peptide supplements have been proven harmful. Safety must be evaluated individually by examining the ingredient, dose, contamination, interactions, and the user’s health status. An absolute judgment about an entire category still exceeds what the evidence can support. PMID: 41895697

Earthquake safety guidance must acknowledge the limits of direct comparative evidence

Drawing on guidance from public-safety agencies, Professor Lin recommends dropping, taking cover, and holding on during an earthquake instead of looking for a “triangle of life.” This is the prevailing practical recommendation. The medical literature included in this review, however, did not provide comparative casualty data for the two approaches in actual earthquakes. That literature alone is therefore insufficient to prove that one approach is invariably safer or to quantify how much harm the “triangle of life” causes. PMID: 37092789

Practical principles for evaluating claims

First ask whether a claim clearly specifies the disease, population, method of use, and measurable outcome. Then determine whether the evidence comes from an in vitro experiment, an animal study, an observational study, or a controlled human trial. If one sentence promises detoxification, infection control, weight loss, anti-aging effects, and treatment of multiple unrelated diseases, suspect that a vague mechanism has been expanded into a universal remedy. Absence of evidence is not proof of ineffectiveness; in vitro activity is not proof of efficacy in humans; and when later research changes a judgment, phrases such as “the literature has been updated” or “science has advanced” should be used to define the evidence boundary.