Products & practices, evidence-checked

Claimed: Omega-3s support heart, brain and eye health.

What research shows: Eating fish twice a week is a well-established healthy pattern. In the 25,871-person VITAL trial, 1 g/day of marine omega-3 supplements didn't reduce major cardiovascular events or cancer overall, though there were possible benefits for heart attacks. So: eat food first, and supplements are optional.

How people use it: Oily fish such as sardines or salmon about twice a week. Algae oil is the plant-based option.

Cautions: Higher doses can raise bleeding risk with blood thinners and atrial-fibrillation risk at high doses. Ask your clinician.

Manson 2019, NEJM (VITAL omega-3) · 🟡 AZ-OMEGA

Claimed: Vitamin D and calcium support bones, muscles and immune function.

What research shows: Vitamin D is essential, and correcting a deficiency is standard care. In VITAL (2,000 IU/day), vitamin D didn't lower cancer or heart-disease rates in mostly non-deficient adults. Evidence for K2 is emerging.

How people use it: Sensible sun, fatty fish and fortified foods. If you supplement, ask for a blood test. NIH lists the RDA as 600–800 IU/day and the upper limit as 4,000 IU/day for adults.

Cautions: Too much causes high calcium. K2 interacts with warfarin.

NIH Office of Dietary Supplements: Vitamin D · 🟢 AZ-VITD

Claimed: Trace minerals support hundreds of enzymes, the thyroid and immunity.

What research shows: These are essential nutrients, and deficiency matters. Extra beyond need isn't proven to help: the SELECT trial (selenium 200 µg) didn't prevent prostate cancer, and excess selenium or iodine can harm the thyroid and other tissues. Zinc lozenges may shorten colds slightly (Cochrane 2024, low certainty).

How people use it: Nuts, seeds, legumes, seafood and iodized salt. Choose supplements only to fill a known gap.

Cautions: Selenium upper limit is 400 µg/day; iodine upper limit is 1,100 µg/day (NIH ODS). Sea moss and kelp can contain excess iodine and heavy metals.

Lippman 2009, JAMA (SELECT); NIH ODS fact sheets · 🟡 AZ-MINERALS

Claimed: B vitamins support energy metabolism and nerves.

What research shows: Essential and well established for correcting a deficiency (e.g. B12 in older adults, vegans, and people on metformin). There's no proven benefit in people who already get enough.

How people use it: Whole grains, legumes, leafy greens, eggs and animal foods. Vegans need a B12 source.

Cautions: High-dose B6 over long periods can cause nerve damage.

NIH ODS: Vitamin B12 · 🟢 AZ-B

Claimed: Supports macular (eye) health.

What research shows: The AREDS2 formula is evidence-based for people with intermediate age-related macular degeneration (JAMA 2013). It isn't shown to prevent AMD in people with healthy eyes.

How people use it: Leafy greens and eggs. Use the AREDS2 formula only on an eye doctor's advice.

Cautions: The original AREDS formula's beta-carotene raises lung-cancer risk in smokers; AREDS2 replaced it.

AREDS2 Research Group 2013, JAMA · 🟢 AZ-EYE

Claimed: Supports cellular energy and 'healthy aging' pathways.

What research shows: Nicotinamide riboside raised blood NAD+ and was well tolerated in a small trial (Martens 2018), but there's no proven clinical benefit. Spermidine didn't improve memory in a 12-month RCT (Schwarz 2022). Urolithin A improved some muscle measures (🟡 LI-S7). The Ca-AKG 'biological age' data come from an uncontrolled company study.

How people use it: Food-based options include fiber and polyphenols (urolithin from pomegranate and walnuts), wheat germ, aged cheese and mushrooms (spermidine).

Cautions: Expensive, with unknown long-term effects. Ask your clinician if you have cancer, since NAD+ pathways are involved in tumor metabolism.

Martens 2018, Nat Commun; Schwarz 2022 JAMA Netw Open (PMID 35616942) · 🟡 AZ-NAD

Claimed: Supports skin, joints and connective tissue.

What research shows: Meta-analyses of RCTs show modest improvements in skin hydration and elasticity with hydrolyzed collagen (de Miranda 2021), though many trials are industry-funded. Bone broth's collagen content is low and highly variable (Alcock 2019).

How people use it: Trials commonly used 2.5–10 g/day of hydrolyzed collagen for 8–12 weeks. Broth is a nourishing food, not a dependable collagen dose.

Cautions: Count it toward your protein intake. Broth can be high in sodium.

de Miranda 2021, Int J Dermatol; Alcock 2019 (PMID 29893587) · 🟡 AZ-COLLAGEN

Claimed: Supports the gut lining and immunity.

What research shows: Small trials found colostrum reduced exercise-induced increases in gut permeability (Davison 2016). There's little evidence for general use.

Cautions: Contains dairy proteins.

Davison 2016, Am J Clin Nutr · 🟡 AZ-COLOSTRUM

Claimed: Supports immunity and focus.

What research shows: Lion's mane improved cognitive scores in a 16-week RCT of 30 adults with mild impairment, and the benefit faded after stopping (Mori 2009). Shiitake raised immune markers (🟡 LI-S15). Blends are rarely tested as sold.

How people use it: Culinary mushrooms several times a week. The trial used 3 g/day of lion's mane powder.

Cautions: Reishi has been linked to rare liver injury and can interact with blood thinners.

Mori 2009, Phytother Res · 🟡 AZ-MUSHROOM

Claimed: Supports blood vessels and circulation.

What research shows: Cocoa flavanols improve blood-vessel function (🟡 LI-S5). In COSMOS (21,442 adults), 500 mg/day of flavanols didn't significantly reduce total cardiovascular events, though cardiovascular deaths fell 27% in a secondary outcome.

How people use it: Unsweetened cacao or 70%+ dark chocolate in small amounts.

Cautions: Chocolate products can contain heavy metals (lead or cadmium), so choose tested brands.

Sesso 2022, Am J Clin Nutr (COSMOS) · 🟡 AZ-CACAO

Claimed: An 'all-in-one' nutrition boost.

What research shows: There are few independent trials of these products as sold. They don't replace whole vegetables (fiber, 🟢 ST-FIBER). MCT oil is quickly turned into ketones, but weight-loss effects are small.

How people use it: Use as a convenience, not a substitute for plants.

Cautions: High doses of vitamins A, K and iodine can stack across products. MCT can upset the stomach.

NCCIH: Using Dietary Supplements Wisely · 🔴 AZ-GREENS

Claimed: Supports gut flora.

What research shows: Some strains have evidence for specific conditions (e.g. a multi-strain probiotic for pouchitis under a GI doctor). For healthy people, fermented foods (🟡 LI-S10) have stronger 'microbiome diversity' data.

How people use it: Fermented foods daily. Take a strain-specific product for a specific purpose.

Cautions: Avoid if you're immunocompromised unless your doctor approves.

NCCIH: Probiotics · 🟡 AZ-PROBIO

Claimed: Supports calm, sleep and mood.

What research shows: Ashwagandha reduced perceived stress in meta-analyses of small RCTs (Alsanie 2026), but there are case series of liver injury (Philips 2023). L-theanine has small RCTs (Hidese 2019). Saffron beat placebo for depressive symptoms in small trials (Hausenblas 2013). '5-HTP + SSRIs' can cause serotonin toxicity. 'Cortisol support' blends are untested.

How people use it: Pair with breathing, sleep and stress practices, which have stronger evidence (🟢 ST-HRVB, 🟢 ST-GOYAL).

Cautions: Don't combine with antidepressants, sedatives or thyroid medication without your doctor. Ashwagandha: stop if you notice jaundice. Avoid in pregnancy.

Alsanie 2026 meta-analysis; NCCIH ashwagandha · 🟡 AZ-CALM

Claimed: Supports blood-sugar and antioxidant pathways.

What research shows: Berberine lowered glucose and HbA1c in meta-analyses of mostly Chinese trials (Dong 2012), with many drug interactions. NAC is a prescription antidote for acetaminophen overdose; supplement uses are still being studied. Quercetin's human evidence is limited.

Cautions: Berberine interacts with diabetes drugs (risk of low blood sugar), cyclosporine and others. Avoid in pregnancy.

Dong 2012 meta-analysis · 🟡 AZ-METAB

Claimed: Supports testosterone and prostate health.

What research shows: Tongkat ali modestly raised testosterone in a meta-analysis of small trials (Leisegang 2022). Fadogia agrestis has only rat data, which included testicular toxicity. Shilajit has one small trial and a risk of heavy-metal contamination. Saw palmetto did no better than placebo for urinary symptoms in a Cochrane review (Tacklind 2012).

Cautions: Get prostate symptoms checked by a doctor. Contamination and adulteration are common in 'male enhancement' products.

Tacklind 2012, Cochrane (saw palmetto); Leisegang 2022 (PMID 36013514) · 🟡 AZ-MALE

Claimed: Supports circulation and healthy inflammation.

What research shows: In a 3-year RCT, nattokinase didn't slow atherosclerosis progression (Hodis 2021). The evidence for serrapeptase is poor (systematic review, Bhagat 2013).

Cautions: Bleeding risk with blood thinners, aspirin, or before surgery.

Hodis 2021 RCT; Bhagat 2013 (PMID 23380245) · 🟡 AZ-CIRC

Claimed: Supports metabolic and immune health.

What research shows: Meta-analyses of small trials show modest effects on lipids, glucose and blood pressure (Musazadeh 2026). Study quality is mixed.

Cautions: May add to the effects of blood-pressure and diabetes medications.

Musazadeh 2026 meta-analysis · 🟡 AZ-NIGELLA

Claimed: Supports muscle.

What research shows: Total protein and resistance training drive muscle growth. BCAAs alone don't maximally stimulate muscle protein synthesis (Wolfe 2017).

How people use it: Spread protein across meals. Whole-food protein comes first.

Cautions: Check with your doctor if you have kidney disease.

Wolfe 2017, J Int Soc Sports Nutr · 🟡 AZ-PROTEIN

Claimed: Supports calm and cognition. Homeopathic 'cell salts' claim to rebalance minerals.

What research shows: Teas are a pleasant way to hydrate (green tea has polyphenol evidence, 🟡 LI-S3). Homeopathic cell salts are too dilute to supply minerals, and reviews find homeopathy no better than placebo (NHMRC 2015; NCCIH).

NCCIH: Homeopathy · 🔴 AZ-TEAS

Claimed: Purges parasites, toxins and 'mucoid plaque'.

What research shows: No controlled studies show commercial detox or parasite cleanses remove toxins or parasites (Klein & Kiat 2015; NCCIH). Your liver and kidneys clear waste. Real parasitic infections need a stool test and prescription treatment. Activated charcoal is an emergency poisoning treatment given by clinicians (Chyka 2005); taken daily it binds medications and nutrients.

How people use it: Support your own detox organs with fiber, water, sleep, less alcohol and cruciferous vegetables (🟡 LI-S16).

Cautions: Wormwood (thujone) can cause seizures. Rue is toxic and can cause miscarriage. Artemisinin self-treatment drives antimalarial resistance. Charcoal and binders block medications. Pau d'arco has toxicity concerns. Never use these in pregnancy.

Klein & Kiat 2015; NCCIH Detoxes and Cleanses · 🔴 AZ-CLEANSE

Claimed: Supports regularity and cholesterol.

What research shows: Psyllium lowers LDL cholesterol (meta-analysis, Zhu 2024) and has an FDA-authorized heart-health claim. Slippery elm has tradition but little data.

How people use it: Start with about 1 tsp a day and increase slowly, with plenty of water.

Cautions: Separate from medications by 2 hours. Not for people with a bowel obstruction or trouble swallowing.

Zhu 2024 meta-analysis · 🟢 AZ-FIBER

Claimed: Supports the liver.

What research shows: A Cochrane review found no significant effect of milk thistle on mortality or complications in alcoholic or hepatitis B/C liver disease (Rambaldi 2007). It's generally well tolerated.

How people use it: Things that do help the liver: less alcohol and added sugar, coffee, movement and weight management.

Cautions: Ragweed allergy. May affect blood sugar.

Rambaldi 2007, Cochrane; NCCIH milk thistle · 🟡 AZ-LIVERHERB

Claimed: Clears the lungs.

What research shows: Mullein is a traditional remedy with lab studies only. Steam can ease nasal congestion subjectively, but Cochrane reviews find no benefit for colds. Eucalyptus oil is toxic if swallowed, especially for children.

How people use it: Use slow nasal breathing, fresh air and hydration (🟡 ST-BREATH). See a doctor for any persistent cough.

Cautions: Scald risk from steam. Keep essential oils away from children and pets.

Singh 2017, Cochrane: Heated, humidified air for the common cold · 🔴 AZ-LUNGHERB

Claimed: Supports circulation; 'internal deodorant' and blood builder.

What research shows: Topical capsaicin is established for some nerve pain. Oral drops for circulation, and chlorophyll's 'blood-building' claims, lack trials.

NCCIH · 🔴 AZ-DROPS

Claimed: Supports liver, lymph and digestion (Barbara O'Neill / Cayce tradition).

What research shows: No trials exist for 'liver detox'. A small study found castor-oil packs eased constipation symptoms in elderly people (Arslan 2011, 🟡 ST-CASTOR1). Taking castor oil by mouth is a strong laxative and can trigger labor (🟢 ST-CASTOR2).

How people use it: A traditional practice: a flannel soaked in castor oil is placed on the abdomen with gentle warmth for 30–60 min, as a restful ritual.

Cautions: External use only. Avoid in pregnancy and on broken skin. Patch-test first.

Arslan 2011 · 🔴 AZ-CASTOR

Claimed: Supports relaxation, muscles and skin. Claims that magnesium is absorbed through the skin.

What research shows: Warm baths relax you. Dead Sea balneotherapy has decades of clinical data for psoriasis (Harari 2024). Absorbing meaningful magnesium through the skin isn't shown (Gröber 2017, 'myth or reality').

How people use it: Warm (not hot) baths of 15–20 min in the evening support sleep onset.

Cautions: People with diabetic neuropathy, heart conditions or pregnancy should avoid hot water.

Gröber 2017, Nutrients · 🟡 AZ-BATHS

Claimed: Pulls toxins out through the feet.

What research shows: An objective test of an ionic footbath found no toxic elements removed from the body; the color change comes from the electrodes and water (Kennedy 2012). Foot pads darken with sweat and moisture. The FTC has acted against detox foot-pad marketers.

How people use it: A warm foot soak is a relaxing ritual, nothing more.

Cautions: Don't use these for diabetic feet or wounds.

Kennedy 2012, J Environ Public Health · 🔴 AZ-FOOTPADS

Claimed: Supports skin health.

What research shows: Topical tea tree oil reduced acne lesions in a meta-analysis (Ye 2026). Ingesting essential oils is unsafe.

How people use it: Diluted topical use only (e.g. 5% tea tree gel in the trials).

Cautions: Can irritate skin and cause contact allergy. Toxic if swallowed. Keep away from cats.

Ye 2026 meta-analysis · 🟡 AZ-OILS

Claimed: Reconnects you with the Earth's electrons, reducing inflammation and improving sleep.

What research shows: The research is small, largely from one group with industry ties (Chevalier 2012 review; a 2019 pilot RCT on bodyworkers' pain). It's biologically speculative and unconfirmed. Time barefoot in nature has its own evidence (🟡 ST-NATURE).

How people use it: Walking barefoot on grass or sand, or sitting outdoors, makes a mindful nature practice.

Cautions: Indoor grounding products connect to your outlet's ground. Check wiring and never use them during storms. Watch for foot injury.

Chevalier 2012; Chevalier 2019 RCT (PMID 30448083) · 🟡 AZ-GROUND

Claimed: Supports skin, recovery and cellular energy (mitochondria).

What research shows: Photobiomodulation has a plausible mechanism (🟡 FQ-PBM). There are small RCTs for skin wrinkles and a few FDA-cleared indications (hair loss, some pain). Results depend on wavelength and dose, and most home devices are untested.

How people use it: Follow the device's cleared instructions. Sessions are typically a few to 20 minutes.

Cautions: Eye protection. Check with your doctor if you're on photosensitizing medications or have had skin cancer.

Wunsch 2014 controlled trial (skin); Mota 2023 RCT (PMID 36780572); FQ-PBM · 🟡 AZ-REDLIGHT

Claimed: Supports heart, circulation, relaxation and 'sweating out toxins'.

What research shows: Finnish observational data link frequent sauna with lower cardiovascular death (🟡 ST-SAUNA). Small Japanese RCTs of far-infrared 'Waon' therapy in heart failure showed modest improvements (Kihara 2016). Sweat removes only trace toxins; the liver and kidneys do the clearing.

How people use it: Typical Finnish practice: 80 °C for 5–20 min, 2–4×/week, then cool down and rehydrate.

Cautions: Avoid with alcohol, during pregnancy, with unstable heart disease, low blood pressure or fever. Ask your doctor first if you have a heart condition.

WAON-CHF 2016, Circ J; Laukkanen (ST-SAUNA) · 🟡 AZ-SAUNA

Claimed: A selective antioxidant that supports energy and recovery.

What research shows: A 2024 systematic review found mostly small, short, heterogeneous human trials with inconsistent results ('Extra healthy or a hoax?').

How people use it: Plain water already does the hydrating (🟢 ST-POPKIN).

Cautions: Hydrogen gas is flammable; use inhalation machines exactly as labeled. Some generators also produce chlorine or ozone.

Systematic review 2024, Int J Mol Sci · 🟡 AZ-H2

Claimed: Kills pathogens and oxygenates the body.

What research shows: The FDA classifies ozone as a toxic gas with no known useful medical application in specific, adjunctive or preventive therapy (21 CFR 801.415). EPA warns that ozone generators harm the lungs. Ozonated water is a sanitizer, not a health drink.

Cautions: Never inhale ozone. Don't run generators in occupied rooms. Use only as a surface or produce sanitizer per the label.

FDA 21 CFR 801.415; EPA on ozone generators · 🔴 AZ-OZONE

Claimed: Improves circulation and energy flow and relieves pain.

What research shows: Meta-analysis of RCTs: static magnets had no significant effect on pain (Pittler 2007). A double-blind trial found neither copper bracelets nor magnetic wrist straps helped rheumatoid arthritis (Richmond 2013). Crystals and 'terahertz' wands have no controlled evidence.

How people use it: If you enjoy crystals or similar items, use them as a prayer or meditation focus. That's a faith or personal practice, not a treatment.

Cautions: Magnets can affect pacemakers and insulin pumps. Copper can cause skin staining or irritation.

Pittler 2007, CMAJ; Richmond 2013 (PMID 24066023) · 🔴 AZ-MAGNET

Claimed: Relieves pain and improves circulation.

What research shows: A 2022 meta-analysis of 381 RCTs found moderate-certainty evidence that TENS reduces pain intensity during or right after use, compared with placebo (Johnson 2022). It's generally safe and FDA-regulated.

How people use it: Follow the device labeling.

Cautions: Not for people with pacemakers, epilepsy, pregnancy (abdomen), or broken skin.

Johnson 2022, BMJ Open (TENS meta-analysis) · 🟡 AZ-EMS

Claimed: Purifies air with negative ions.

What research shows: There's no controlled evidence that salt lamps or diffusers change air quality or health. Clinical halotherapy (salt-room inhalation) has only small, low-quality studies.

How people use it: Ventilation and a HEPA filter are the evidence-based options for indoor air.

Cautions: Salt lamps are toxic to pets if licked.

EPA indoor air guidance · 🔴 AZ-SALTAIR

Claimed: Clean water; checking your body's 'alkalinity'.

What research shows: Certified filters (NSF/ANSI standards) reduce specific contaminants; check the certification for the contaminant you care about. Urine pH reflects diet and kidney work, not blood pH, which the body holds at 7.35–7.45 (🟢 ST-FENTON).

How people use it: Test your local water report. Filters are worth using; pH strips aren't a health gauge.

Cautions: Change filter cartridges on schedule.

NSF standards; Fenton 2016 · 🟡 AZ-WATER

Claimed: Tracks HRV, sleep and oxygen.

What research shows: Validation studies show wearables estimate heart rate well, HRV moderately well and sleep stages less well (Miller 2022). FDA notes over-the-counter pulse oximeters aren't FDA-reviewed and can be less accurate on darker skin, with poor circulation, or with nail polish.

How people use it: Use HRV trends to see the effects of resonance breathing, sleep and alcohol. That's the 'measured resonance' idea in practice.

Cautions: Don't make medical decisions from consumer devices. Seek care for shortness of breath or bluish lips regardless of the reading.

Miller 2022, Sensors; FDA Pulse Oximeter Basics · 🟡 AZ-TRACK

Claimed: Protects against harmful EMF from phones and 5G.

What research shows: WHO and the National Cancer Institute find no established health effects from everyday radiofrequency exposure below international limits. Shielding products aren't needed, and some make phones transmit harder.

How people use it: If you want less screen time and better sleep, keep the phone out of the bedroom. That's a real sleep-hygiene habit.

WHO 5G Q&A; NCI cell phone fact sheet · 🔴 AZ-EMF