Safety & Harms 50 topics · 64 claims

Does glyphosate cause non-Hodgkin lymphoma?

Unresolved. Ever being exposed shows no clear added risk; a modestly higher risk appears only in the most heavily exposed farm applicators, and the largest long-term study found none. No study has looked at glyphosate in food.

glyphosate causes non-Hodgkin lymphoma

Does glyphosate cause kidney disease?

A kidney disease epidemic in farming regions of Sri Lanka and Central America prompted this, but the leading explanation is heat stress and dehydration in outdoor workers. The one study measuring both found the job mattered and glyphosate levels did not.

glyphosate causes kidney disease

Is the glyphosate in your food harming you?

The studies suggesting harm are mostly the same 4,700 people analysed over and over, and they share a flaw: poor kidney function raises urinary glyphosate, so cause and effect may run backwards. Measured dietary intake sits at a tiny fraction of the safety limit.

glyphosate residues causes adverse health effects

Does glyphosate disrupt human hormones?

Several studies link more glyphosate in urine to lower sex-hormone levels, but they only show an association, not cause, and one study measuring glyphosate in blood and tissue found no link. Much of the animal evidence tested the full weedkiller formulation rather than glyphosate itself.

glyphosate alters human hormone levels

Does glyphosate damage your gut bacteria?

The theory is sound, because gut bacteria have the exact pathway glyphosate blocks. But it has never been tested in a single human. The evidence is rodents, mostly at doses far above anything you would eat.

glyphosate alters gut microbiome

Does glyphosate cause celiac disease?

This comes from one 2013 paper that noticed glyphosate use and celiac diagnoses rose at the same time. Nobody has ever tested it. Celiac diagnoses also rose because doctors started screening for it.

glyphosate causes celiac disease

Is testosterone therapy safe for the prostate?

On the cancer question, the modern evidence is reassuring: the old fear that testosterone feeds prostate cancer is not supported. Randomized trials, large registries, and even prostate-cancer-survivor studies show no increased risk, and some show lower risk. The main caveat is that the trials weren't long enough to be the final word, so men on testosterone should still get routine PSA/prostate monitoring.

testosterone therapy does not increase prostate cancer risk

Is testosterone therapy safe for your heart?

Mostly reassuring, not fully settled. The big 2023 TRAVERSE trial found no increase in major cardiac events (heart attack, stroke, cardiac death) — putting an old scare to rest — but it did find more atrial fibrillation and blood clots in the lungs. So: probably safe for major events in the right patients, with a real, unresolved signal for irregular heartbeat and clots.

testosterone therapy does not increase cardiovascular risk

Is testosterone therapy safe for the heart in older at-risk men?

The large TRAVERSE RCT found TRT non-inferior to placebo for major cardiac events over about 3 years, though it raised atrial fibrillation, pulmonary embolism, and acute kidney injury and does not speak to longer horizons.

testosterone replacement therapy is noninferior to placebo

aspartame increases cancer risk

aspartame increases cancer risk

aspartame worsens phenylalanine control in phenylketonuria

aspartame worsens phenylalanine control in phenylketonuria

Is creatine safe to take long-term?

Yes — it has one of the strongest safety records of any supplement, with no harm to kidney, liver, or heart markers in healthy adults across trials lasting years. Claims that literally everyone should take it, including pregnant or clinical populations, go further than the evidence.

creatine is safe at healthy adults

Is creatine safe for your kidneys?

Yes — for healthy people at normal doses. Creatine nudges up a blood marker (creatinine) that can look like kidney trouble on a test, but meta-analyses and even genetic studies find no actual harm. Existing kidney disease is a separate conversation with your doctor.

creatine does not worsen kidney function

Do pickled vegetables raise throat/esophageal-cancer risk?

Possibly — two analyses found pickled vegetables roughly doubled the odds of esophageal cancer, along the same salt/pickling pathway. But the signal weakened to non-significant in the strongest (prospective) studies, so it's a leaning concern rather than settled fact.

fermented vegetables increases esophageal cancer risk

Do kimchi and pickled vegetables raise stomach-cancer risk?

The evidence says yes, they're associated with higher stomach-cancer risk — several studies point the same way, and kimchi specifically showed about double the odds in Korean populations. The likely cause is the salt and nitrites from pickling, not the vegetables themselves (fresh vegetables actually lower risk). It's mostly lower-quality data, so it's a real red flag rather than proof — but it means fermented veg aren't a free pass, especially in large, very salty amounts.

fermented vegetables increases gastric cancer risk

Does the keto diet raise bad cholesterol?

Yes, often dramatically in lean people, though whether that rise carries normal heart risk is unsettled.

ketogenic diet increases LDL cholesterol

Does starting the ketogenic diet commonly cause side effects like constipation, nausea and fatigue?

Yes — the "keto flu" is real: constipation, nausea, vomiting and lethargy are commonly reported on initiation, usually mild and manageable but genuine.

ketogenic diet causes gastrointestinal and induction adverse effects

Do artificial sweeteners harm your heart and metabolism?

Probably not — the scary signal is likely backwards, and swapping sugar for them looks neutral in trials.

non-nutritive sweeteners causes cardiometabolic harm

Do artificial sweeteners cause cancer?

The evidence says no. Large reviews have repeatedly looked and found no cancer link at the amounts people actually consume. The scare traces back to old rat studies using doses far beyond any human diet. This is one of the clearer 'debunked' answers in the library.

non-nutritive sweeteners increases cancer risk

Do pesticides cause Parkinson's disease?

For farm workers and people living near sprayed fields, this is one of the more credible pesticide risks, particularly for paraquat. But no study has ever linked it to the residue levels on supermarket food.

pesticide exposure increases Parkinson's disease risk

Do pesticides make it harder to conceive?

For people working with them, probably. For ordinary consumers the evidence is thin, relies on indirect measures, and one large study found the opposite of what you would expect.

pesticide exposure decreases fertility

Is quercetin bad for your kidneys?

The evidence runs the other way: across sixteen studies quercetin protected kidneys from other damage rather than causing harm. The lone injury signal used injected, not oral, doses in rodents. What is genuinely missing is a proper human high-dose safety trial.

quercetin causes kidney injury

Can quercetin interfere with prescription medications?

It blocks the CYP3A4 enzyme in the lab, and raises drug levels in rats. Whether that happens in people at supplement doses is untested, and in the one direct check the effect did not even carry across two similar drugs. Mention it to your prescriber if you take a narrow-margin medication.

quercetin inhibits CYP3A4

acesulfame-K causes genotoxicity

acesulfame-K causes genotoxicity

added sugar causes dental caries

added sugar causes dental caries

Does fasting every other day raise bad cholesterol?

No — most trials show no rise versus ordinary calorie cutting, with only one outlier suggesting harm.

alternate-day fasting increases LDL cholesterol

Is boswellia safe to take?

Generally yes — it's well-tolerated in trials, usually gentler on the stomach than anti-inflammatory drugs, with mild digestive upset the main complaint. Long-term data are thinner.

boswellia is safe at supplement doses

Is bromelain safe to take?

Generally safe, with a few real caveats: it can trigger reactions if you're allergic to pineapple, it mildly thins the blood (care with blood thinners and around surgery), and it can increase absorption of some antibiotics.

bromelain is safe at supplement doses

Is chlorpyrifos dangerous to developing brains?

Enough that US regulators pulled it from food use in 2021, and animal studies support harm at surprisingly low doses. But the human studies looking at ordinary food-level exposure came back null, so the risk is about high exposure, not groceries.

chlorpyrifos causes developmental neurotoxicity

Do pesticides in food cause cancer?

Eleven studies bear on this and not one of them answers it. Most are about farm workers, whose exposure is thousands of times higher than a shopper's. The rest use 'buys organic' as a rough stand-in for pesticide dose. Nobody has measured what people actually eat and followed them for cancer.

dietary pesticide exposure increases cancer risk

Are the pesticide residues on ordinary food harming you?

The best evidence says no. A 68,844-person Swedish study followed for 15 years found no harm, and Europe's monitoring of over 135,000 food samples puts typical exposure at a small fraction of the safety limit.

dietary pesticide residues causes adverse health effects

Does the Dirty Dozen list tell you which produce is actually risky?

Not really. It ranks by how often residue is detected, not by how much. When researchers ran the dose calculations on the list's own fruits and vegetables, every single one came in under the safety threshold, for adults and children alike.

EWG Dirty Dozen list predicts consumer pesticide health risk

Do pesticides mess with your hormones?

Some do, some do not, and some push in opposite directions in the very same study. 'Pesticides' covers hundreds of unrelated chemicals, so a single answer here would be misleading.

endocrine-disrupting pesticides alters human hormone levels

fava bean causes hemolysis in G6PD deficiency

fava bean causes hemolysis in G6PD deficiency

Does fiber ease constipation from Ozempic-style drugs?

Untested: no trial has looked at fibre in people taking these drugs. Fibre does help ordinary constipation, so it is plausible, and experts advise adding it slowly because the drug already slows digestion.

dietary fiber mitigates GLP-1 RA GI side effects (constipation)

Does fructose damage the liver more than the same calories from glucose/starch?

Fructose does drive hepatic de novo lipogenesis and can raise liver fat, but controlled trials show the harm tracks excess calories — isocaloric fructose is not clearly worse than other carbohydrate, so the calorie-independent framing overstates the evidence.

dietary fructose causes hepatic fat accumulation and NAFLD independent of caloric load

Do GLP-1 drugs commonly cause stomach and GI side effects?

Very commonly nausea, vomiting, diarrhea and constipation — usually mild/transient and tied to delayed gastric emptying — with a small but real increase in rarer events like gastroparesis and bowel obstruction.

GLP-1 receptor agonists causes GI side effects via delayed gastric emptying (nausea, vomiting; rare gastroparesis)

Can green tea extract supplements damage your liver?

Yes, rarely — concentrated green-tea-extract supplements, especially high doses on an empty stomach, can cause serious liver injury; regulators added warning labels, and some people are genetically more susceptible. Brewed green tea is safe. Drink the tea; be cautious with the pills.

green tea extract causes liver injury

thermal paper receipts causes adverse health effects

thermal paper receipts causes adverse health effects

Does frying seed oils create toxic aldehydes?

True in chemistry/lab — heating PUFA-rich oils reliably produces reactive aldehydes that are cytotoxic and genotoxic to cells, but whether the amounts ingested at normal dietary doses cause human disease is far weaker and largely inferred from confounded fried-food cohorts.

repeatedly heated/fried seed oils produces reactive cytotoxic/genotoxic aldehydes (4-HNE, trans-2-alkenals)

Does eating pesticide-heavy fruit and veg lower your sperm count?

One study found a striking drop, but nobody independent has ever replicated it, the same team's second population showed nothing, and no man's actual pesticide level was measured. Independent research finds more produce means better sperm quality. Eat the fruit and veg.

high-pesticide-residue produce decreases sperm count

Is a high-protein diet safe for your kidneys?

For people with healthy kidneys, yes. High protein intake does not damage kidney function in healthy adults, and this is well established. The kidney concern is real only for people who ALREADY have significant kidney disease, where protein needs to be managed carefully. So unless you have a diagnosed kidney problem, high protein isn't a kidney risk.

high protein intake does not worsen kidney function in healthy adults

Does chronically high insulin raise cancer risk?

Yes for endometrial and colorectal cancer the association is robust, weaker/age-restricted for postmenopausal breast, and mixed for pancreatic, so the association is real but varies by cancer type.

chronic hyperinsulinemia increases risk of breast/colon/pancreatic/endometrial cancer

Can keto plus a diabetes drug cause dangerous ketoacidosis?

Yes, combining a very low-carb diet with an SGLT2-inhibitor drug is a genuine, well-documented risk even when blood sugar looks normal.

ketogenic diet with SGLT2 inhibitor causes euglycemic ketoacidosis

Does very high cholesterol on low-carb diets still clog arteries?

Unknown for this specific group — nobody has yet followed these people's arteries in a sound study, and the one trial that claimed to was retracted in 2026. Everywhere else, high "bad" cholesterol causes plaque however it got high, and nothing shows this pattern is exempt. Measure ApoB; do not assume it is benign.

lean mass hyper-responder phenotype causes coronary atherosclerosis progression

Do low-carb diets shorten your life?

Unclear — evidence is mixed: animal-based versions look harmful, plant-based protective, from data that can't prove cause.

low-carbohydrate diet increases all-cause mortality

monk fruit is safe at safe to consume

monk fruit is safe at safe to consume

Are neonicotinoids harming human brains?

The harm to bees is real and well established, but that is a different question. For people, there are two studies in Chinese children and little else, and these chemicals were designed to target insect nerve receptors rather than mammalian ones.

neonicotinoid exposure causes human neurotoxicity

Does working with pesticides damage sperm quality?

There is a real signal, strongest for sperm movement and DNA damage rather than count. But much of the apparently large evidence base is the same studies reviewed repeatedly, and the cleanest occupational studies disagree.

occupational pesticide exposure decreases semen quality

Does switching to organic food lower the pesticide levels in your body?

Yes, quickly and substantially, within about a week. But that measures exposure, not health, and if you live near sprayed farmland the drift matters more than your diet does.

organic diet decreases urinary pesticide metabolites

Does buying organic actually reduce your pesticide exposure?

Yes, measurably. Trials show large drops in pesticide levels in urine. But organic is not pesticide-free: organic farming uses its own approved pesticides, and tests looking only for synthetic ones will not see them.

organic produce decreases pesticide residue exposure

Does warning people about pesticides make them eat less fruit and veg?

Three studies touch on this and none of them ran the experiment. For all the pesticide warning that exists, nobody appears to have tested whether it changes what people actually buy. The one real-world study found shoppers bought visibly stained tomatoes anyway, because they had no alternative.

pesticide risk messaging decreases fruit and vegetable consumption

Are pesticides causing the global decline in sperm counts?

Forty-seven studies, and not one tests this. Around a dozen ask whether sperm counts are really falling, which is itself disputed. The rest show pesticides can harm sperm in heavily exposed men. Nobody has joined the two together, or worked out how much of any decline pesticides would account for.

pesticides causes global sperm count decline

phlorizin is safe at food-relevant doses

phlorizin is safe at food-relevant doses

Do the lectins/antinutrients in properly prepared plant foods harm healthy people?

No — lectins cause acute poisoning only from raw/undercooked beans; properly cooked plant foods are not shown to harm healthy people, and high plant-food diets track with lower mortality.

dietary lectins and antinutrients causes harm in healthy humans at normal culinary intakes

Are plant polyphenols (from fruit, tea, etc.) net poisons rather than beneficial?

No — higher polyphenol/flavonoid intake is consistently associated with LOWER mortality; the hormesis mechanism is real but the net population effect is benefit, not harm.

plant polyphenols is a net toxins harmful to humans rather than beneficial

Does pesticide exposure in pregnancy lower a child's IQ?

In farming communities with high exposure, the evidence points that way. In European populations at ordinary dietary exposure levels, studies come back null. Some headline findings turn out to be about flame retardants, not pesticides.

prenatal organophosphate exposure decreases child IQ

Does refining seed oils create chemicals regulators cap, like trans fats and 3-MCPD?

True in food chemistry — high-temperature deodorization measurably generates 3-MCPD esters, glycidyl esters (a probable carcinogen precursor) and small amounts of trans fats; the contaminant chemistry is well documented (EFSA-relevant), though typical dietary exposures are low and human-harm estimates rest on animal toxicology + margin-of-exposure modeling, not human outcome trials.

industrial refining of seed oils (high-heat deodorization) produces process contaminants (3-MCPD esters, glycidyl esters, trans fats)

SGLT1 inhibition causes gastrointestinal side effects

SGLT1 inhibition causes gastrointestinal side effects

Do statins reduce major cardiovascular events in patients with established cardiovascular disease?

Yes — among the best-supported claims in cardiology: large RCTs and CTT meta-analyses show a consistent ~20-25% relative risk reduction in major vascular events per ~1 mmol/L LDL lowering.

statins decreases major adverse cardiovascular events (secondary prevention)

Is stevia safe to consume?

By the weight of the evidence, yes - it's not genotoxic or cancer-causing at normal amounts, and regulators (FDA, EFSA) set a safe daily intake of about 4 mg per kg of body weight. The old cancer scare doesn't hold up. Honest caveat: a lot of the foundational safety testing was industry-funded, but independent reviews reach the same reassuring conclusion.

stevia is safe at safe to consume

Does a sucralose byproduct damage your DNA?

No — the alarming lab studies are disputed, and a 2026 safety review found no concern.

sucralose-6-acetate causes genotoxicity

If you swap butter and animal fat for vegetable oils high in linoleic acid, do you die sooner?

The recovered old-trial data are split: vegetable-oil swaps cut cholesterol but gave no survival benefit and in the Sydney trial significantly raised deaths, yet larger pooled RCTs show the swap actually reduces heart-disease events, so a blanket "raises mortality" claim is not supported.

replacing saturated fat with linoleic-acid vegetable oil increases mortality / coronary heart disease

Does washing fruit and vegetables get the pesticides off?

Partly. Plain water removes roughly a third; baking soda or vinegar a bit more. But that only works for residue sitting on the surface. Anything the plant absorbed into its flesh stays there, and peeling beats washing for those.

washing produce decreases pesticide residues