Research library

The published research behind the ingredients we sell, grouped by ingredient, with who was studied, what was found and a link to every paper.

We built this library for curious customers. Every entry links to the study on PubMed and to its DOI, so you can read the original yourself. Each summary says who was studied: cells, mice or people, healthy volunteers or patients. These studies looked at individual ingredients, usually in different amounts or forms from the formulas in our shop; they explain why an ingredient interests researchers and are not a promise of what any product will do. Food supplements are not medicines and are not intended to treat, cure or prevent any disease.

Fisetin · Quercetin · β-NMN · MSM · Digestive enzymes · Glutathione · Zinc and selenium · Echinacea · Lactoferrin · Modified citrus pectin · Chlorella · Sulforaphane · Milk thistle (silymarin) · Curcumin and piperine · White willow bark · Boswellia serrata · Ashwagandha · Blueberry · Shilajit · Fasting, sleep and activity

Fisetin

A flavonol found in strawberries, apples and onions; Novalytic’s comes from Cotinus coggygria extract. Found in: Novalytic.

• In cells, mice and human fat tissue samples (2018). Of ten flavonoids screened, fisetin was the most active against senescent cells, which have stopped dividing but linger in tissues. Given to old mice late in life, it reduced senescence markers in several tissues; the study also measured how long the mice lived, and that result is in the paper. It also reduced senescence in a subset of cells in human fat tissue in the laboratory.

  Yousefzadeh MJ et al. (2018). Fisetin is a senotherapeutic that extends health and lifespan. EBioMedicine. PubMed 30279143 · doi:10.1016/j.ebiom.2018.09.015

• In 15 healthy volunteers, single doses (2022). In a randomised, double-blind crossover study, each volunteer took two single doses 10 days apart, in random order: 1,000 mg of plain fisetin and 1,000 mg of a formulation that encapsulates fisetin in fenugreek fibre (FF-20, supplying 192 mg of fisetin). Over 12 hours, the amount of fisetin reaching the blood was 26.9 times greater with the formulation than with plain fisetin. No significant adverse events were seen; two minor stomach complaints, bloating and a loss of appetite, were reported alike with both forms. The study was funded by Akay Natural Ingredients, which makes the formulation and holds patents on its technology; four authors work for Akay and two for Life Extension, which sells the formulation.

  Krishnakumar IM et al. (2022). Enhanced bioavailability and pharmacokinetics of a novel hybrid-hydrogel formulation of fisetin orally administered in healthy individuals: a randomised double-blinded comparative crossover study. Journal of Nutritional Science. PubMed 36304817 · doi:10.1017/jns.2022.72

• Review of cell, animal and early human studies (2024). Researchers in Copenhagen and Los Angeles review laboratory and animal research on fisetin as a senotherapeutic, a compound that targets senescent cells, together with phase I and II trials in various patient groups. They conclude that further studies are needed to establish fisetin’s safety, pharmacokinetics (how the body absorbs and processes it) and efficacy as a senotherapeutic, and to find the best dose. Mayo Clinic, where two of the authors used to work, holds patents on senolytic drugs.

  Tavenier J et al. (2024). Fisetin as a senotherapeutic agent: evidence and perspectives for age-related diseases. Mechanisms of Ageing and Development. PubMed 39384074 · doi:10.1016/j.mad.2024.111995

• In old mice and human cells (2024). Fisetin reduced markers of senescence in human endothelial cells, the cells that line blood vessels, grown in the laboratory. Old mice aged 27 months, given fisetin by mouth at 100 mg/kg a day on an intermittent schedule (one week on, two weeks off, one week on), had lower markers of senescence in their arteries, better function of the artery lining and less arterial stiffness than old mice given an inactive solution. This was a study in mice and cells, so it does not show what happens in people.

  Mahoney SA et al. (2024). Intermittent supplementation with fisetin improves arterial function in old mice by decreasing cellular senescence. Aging Cell. PubMed 38062873 · doi:10.1111/acel.14060

Quercetin (Quercefit® phytosome)

A flavonol from onions, apples and capers. Quercefit® binds it to sunflower lecithin to improve absorption. Found in: Novalytic, InsuLess, Liberate.

• In 12 healthy adults (2019). In a randomised crossover study, quercetin phytosome produced blood quercetin levels up to 20 times higher than unformulated quercetin, with no notable side effects. The study was carried out by Indena, which makes the ingredient.

  Riva A et al. (2019). Improved oral absorption of quercetin from Quercetin Phytosome®, a new delivery system based on food grade lecithin. European Journal of Drug Metabolism and Pharmacokinetics. PubMed 30328058 · doi:10.1007/s13318-018-0517-3

• Systematic review and meta-analysis of 31 human studies (2025). Pools studies, published up to July 2024, that measured quercetin in people’s blood or urine after different forms of quercetin and different foods. Compared with plain quercetin (the aglycone), a lecithin phytosome form raised bioavailability 20.1-fold and a form encapsulated in fenugreek fibre and lecithin 62-fold; some sugar-bound forms of quercetin were also better absorbed, and taking quercetin with dietary fat or fibre roughly doubled bioavailability. One author reports consulting for, and research funding from, Access Business Group, and research funding from The Product Makers.

  Liu L et al. (2025). Improving quercetin bioavailability: a systematic review and meta-analysis of human intervention studies. Food Chemistry. PubMed 40037045 · doi:10.1016/j.foodchem.2025.143630

• Meta-analysis of 13 placebo-controlled trials, 249 participants (2023). The trials gave quercetin, at 1,000 mg a day in all but one, to healthy people from sedentary to well trained, mostly young men, for at least a week, or as a single dose, before muscle-damaging exercise. Pooled results showed lower muscle soreness and lower markers of oxidative stress after exercise with quercetin than with placebo, and lower creatine kinase, a marker of muscle damage, 24 to 48 hours after exercise; the inflammatory marker IL-6 did not differ. Four of the five trials that measured muscle function found better recovery with quercetin. The authors had some concerns about the risk of bias in every trial and advise caution, as few trials were pooled for each measure.

  Rojano-Ortega D et al. (2023). Quercetin supplementation promotes recovery after exercise-induced muscle damage: a systematic review and meta-analysis of randomized controlled trials. Biology of Sport. PubMed 37398956 · doi:10.5114/biolsport.2023.121320

β-NMN (nicotinamide mononucleotide)

A direct precursor of NAD⁺, the coenzyme cells use to produce energy. Found in: Novalytic.

• In 10 healthy Japanese men (2020). Single oral doses of 100, 250 and 500 mg were safe and efficiently metabolised, with no significant changes in heart rate, blood pressure, oxygen saturation or body temperature over five hours.

  Irie J et al. (2020). Effect of oral administration of nicotinamide mononucleotide on clinical parameters and nicotinamide metabolite levels in healthy Japanese men. Endocrine Journal. PubMed 31685720 · doi:10.1507/endocrj.EJ19-0313

• Meta-analysis of 15 randomised trials (2026). The trials, mostly small and short, gave adults from healthy volunteers to people with health conditions 250–2,000 mg of NMN (or a related NMN preparation) a day for 14 days to 24 weeks, against a placebo or no NMN. In the 10 trials, with 383 participants, that reported safety data, NMN did not increase overall, serious or system-specific adverse events or withdrawals due to adverse events, and did not significantly raise the liver enzymes ALT and AST. It had no significant effect on body weight, BMI, fasting glucose, HbA1c or blood lipids; the authors saw no broad metabolic benefit and call for larger, longer trials.

  Yang W et al. (2026). Safety and metabolism-related outcomes of oral nicotinamide mononucleotide supplementation in adults: a systematic review and meta-analysis. Nutrients. PubMed 42514320 · doi:10.3390/nu18142251

• Meta-analysis of 10 randomised trials in older adults (2025). Six placebo-controlled trials tested NMN and four tested nicotinamide riboside, another NAD⁺ precursor, at 250–2,000 mg a day for 3 to 24 weeks, in groups with an average age of 60.9 to 83 years. NMN had no significant effect on muscle mass, grip strength, walking speed or a chair-stand test, and did not improve knee extension strength or physical performance scores. The authors conclude that current evidence does not support NMN or nicotinamide riboside for preserving muscle mass and function in adults with an average age over 60.

  Prokopidis K et al. (2025). The effect of nicotinamide mononucleotide and riboside on skeletal muscle mass and function: a systematic review and meta-analysis. Journal of Cachexia, Sarcopenia and Muscle. PubMed 40275690 · doi:10.1002/jcsm.13799

• In 80 healthy middle-aged adults, 60 days (2023). In a randomised, double-blind, placebo-controlled trial, participants took a placebo or 300, 600 or 900 mg of NMN once a day. Blood NAD levels rose in all three NMN groups compared with placebo, highest in the 600 and 900 mg groups, and no safety issues were found. Six-minute walking distance increased more with NMN than with placebo, while a measure of insulin resistance (HOMA-IR) did not differ. The trial was fully funded by Aba Chemicals and Abinopharm, which developed and made the NMN used, and three authors work for them.

  Yi L et al. (2023). The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial. GeroScience. PubMed 36482258 · doi:10.1007/s11357-022-00705-1

MSM (methylsulfonylmethane)

A naturally occurring source of dietary sulfur. Found in: Novalytic.

• Review of animal and human research (2017). Summarises the uses studied for MSM and its safety; MSM was well tolerated by most people at up to four grams a day. Two authors disclose links to MSM suppliers.

  Butawan M, Benjamin RL, Bloomer RJ (2017). Methylsulfonylmethane: applications and safety of a novel dietary supplement. Nutrients. PubMed 28300758 · doi:10.3390/nu9030290

• In 22 healthy adults running a half-marathon (2017). In a randomised, double-blind, placebo-controlled trial, runners took 3 g of MSM (OptiMSM®) or a placebo daily for 21 days before the race and two days after. Running the race raised markers of oxidative stress and muscle damage, and muscle and joint pain; MSM made no statistically significant difference to any of them, though muscle and joint pain scores were lower with MSM by margins the authors call clinically, but not statistically, significant. The trial enrolled fewer runners than its power calculation required. Bergstrom, which makes OptiMSM®, supplied the capsules and funded the laboratory tests; the first author worked there at the time.

  Withee ED et al. (2017). Effects of methylsulfonylmethane (MSM) on exercise-induced oxidative stress, muscle damage, and pain following a half-marathon: a double-blind, randomized, placebo-controlled trial. Journal of the International Society of Sports Nutrition. PubMed 28736511 · doi:10.1186/s12970-017-0181-z

Digestive enzymes

Enzymes that split food into smaller units: protease acts on protein, lipase on fat, amylase and maltase on starch and its sugars, invertase on table sugar and cellulase on plant fibre. Found in: Novalytic.

• In 30 healthy middle-aged and older adults, three-week crossover (2026). In a randomised, double-blind crossover trial, participants took a capsule of six microbial enzyme preparations (three proteases, a lipase, an amylase and a glucoamylase) or a placebo with their two largest meals each day for three weeks, then ate a test meal of chicken, peas, mashed potato, milk and butter with the same capsule. In the 25 participants analysed, blood amino acid levels over the next five hours did not differ overall, but leucine peaked sooner with the enzymes (121 against 141 minutes on average), and blood glucose and free fatty acids were higher. The study was funded by BIO-CAT, which supplied the blend and has filed a patent application related to it; one author worked there at the time.

  Deutz MT et al. (2026). Oral multienzyme supplementation alters postprandial plasma nutrient concentrations after a mixed meal in healthy middle-aged and older adults: a randomized, double-blind, placebo-controlled, crossover trial. Journal of Nutrition. PubMed 41662956 · doi:10.1016/j.tjnut.2026.101400

• In 24 healthy young adults, single doses (2024). In a randomised, double-blind crossover trial, participants drank 25 g of pea protein isolate mixed with 250 mg of a blend of three protease preparations from Aspergillus fungi, or with a placebo. Total amino acids in the blood were higher with the proteases over five hours, and leucine, branched-chain, essential and total amino acids were all higher in the first two hours; insulin did not differ, and blood glucose was higher with the proteases. The study was funded by BIO-CAT, which distributes the protease blend, has filed a patent application related to the findings and employs three of the authors.

  Paulussen KJM et al. (2024). Acute microbial protease supplementation increases net postprandial plasma amino acid concentrations after pea protein ingestion in healthy adults: a randomized, double-blind, placebo-controlled trial. Journal of Nutrition. PubMed 38467279 · doi:10.1016/j.tjnut.2024.03.009

Glutathione

The most abundant antioxidant the body makes inside its own cells. Found in: InsuLess.

• In 54 healthy non-smoking adults, six months (2015). Daily oral glutathione at 250 or 1,000 mg raised glutathione levels in blood compared with baseline; at the higher dose, levels in red blood cells, plasma and lymphocytes rose by 30–35% after six months, and returned to baseline after a month off.

  Richie JP Jr et al. (2015). Randomized controlled trial of oral glutathione supplementation on body stores of glutathione. European Journal of Nutrition. PubMed 24791752 · doi:10.1007/s00394-014-0706-z

• In 20 adults with metabolic syndrome, three-week crossover (2015). A sublingual (under-the-tongue) glutathione tablet raised plasma glutathione and the reduced-to-oxidised glutathione ratio more than glutathione swallowed as a capsule. The tablet is a different product from InsuLess, and the study was sponsored by the tablet’s maker, Laboratoires Le Stum.

  Schmitt B et al. (2015). Effects of N-acetylcysteine, oral glutathione (GSH) and a novel sublingual form of GSH on oxidative stress markers: a comparative crossover study. Redox Biology. PubMed 26262996 · doi:10.1016/j.redox.2015.07.012

• In 40 healthy adults, four weeks (2011). In a randomised, double-blind, placebo-controlled trial, glutathione taken by mouth at 500 mg twice a day made no significant difference to two urinary markers of oxidative stress, or to glutathione levels in red blood cells, compared with placebo. Thirty-nine of the participants completed the study.

  Allen J, Bradley RD (2011). Effects of oral glutathione supplementation on systemic oxidative stress biomarkers in human volunteers. Journal of Alternative and Complementary Medicine. PubMed 21875351 · doi:10.1089/acm.2010.0716

• In 12 healthy non-smoking adults aged 50 to 80, one month (2018). In a pilot study with no placebo group, participants were randomly assigned to 500 or 1,000 mg a day of liposomal glutathione taken by mouth, six to each dose. Glutathione rose within a week in whole blood, red blood cells, plasma and peripheral blood mononuclear cells (a group of white blood cells), with the largest rises after two weeks: up to 40% in whole blood and about double in the white blood cells. A marker of oxidative stress (plasma 8-isoprostane) fell. Natural killer cell activity and lymphocyte proliferation were also measured; those results are in the paper. The authors call the findings preliminary: the study was small, not every change was statistically significant and no difference was found between the two doses. Researched Nutritionals, the company that supplied the liposomal glutathione, funded the study, with part support from the US National Institutes of Health.

  Sinha R et al. (2018). Oral supplementation with liposomal glutathione elevates body stores of glutathione and markers of immune function. European Journal of Clinical Nutrition. PubMed 28853742 · doi:10.1038/ejcn.2017.132

• In 15 healthy adults, single dose (2019). In a single-blind, randomised, placebo-controlled crossover study, a researcher placed 1 ml of a nano-sized (non-liposomal) glutathione solution containing 200 mg under each participant’s tongue, where it was held for 90 seconds before the rest was swallowed. Over the next two hours, glutathione in red blood cells and the total blood glutathione pool rose more than after a placebo solution, although not every measure differed. The authors call for research into whether this form affects oxidative stress. Pelame, LLC funded the study, supplied the solutions, recommended how to give them and suggested minor changes to the study design and the manuscript.

  Bruggeman BK et al. (2019). The absorptive effects of orobuccal non-liposomal nano-sized glutathione on blood glutathione parameters in healthy individuals: a pilot study. PLoS One. PubMed 31039164 · doi:10.1371/journal.pone.0215815

Zinc and selenium

Two essential trace minerals that must come from the diet: Novalytic contains zinc as zinc bisglycinate, and InsuLess contains zinc from guava and selenium from mustard seed. Found in: Novalytic, InsuLess.

• In 30 young women, six weeks (2015). Groups of ten took 60 mg of zinc a day, a dose the authors call moderately high, as zinc glycinate or zinc gluconate, or a placebo. Plasma zinc rose in everyone given zinc glycinate, while zinc gluconate and placebo produced no significant overall change. Red blood cell superoxide dismutase activity, a marker used to detect copper deficiency caused by zinc, did not change in any group. The lead author now uses zinc glycinate in products of his own start-up company, though he did not when the study was done.

  DiSilvestro RA, Koch E, Rakes L (2015). Moderately high dose zinc gluconate or zinc glycinate: effects on plasma zinc and erythrocyte superoxide dismutase activities in young adult women. Biological Trace Element Research. PubMed 25877802 · doi:10.1007/s12011-015-0334-3

• In 31 nursing home residents with low blood zinc, three months (2016). In a randomised, double-blind, placebo-controlled trial, residents aged 65 or over with low serum zinc took 30 mg of zinc a day or a placebo containing 5 mg. Serum zinc rose 16% more in the 30 mg group, though not everyone who started with the lowest levels reached an adequate concentration. T cell numbers and proliferation were also measured; those results are in the paper.

  Barnett JB et al. (2016). Effect of zinc supplementation on serum zinc concentration and T cell proliferation in nursing home elderly: a randomized, double-blind, placebo-controlled trial. American Journal of Clinical Nutrition. PubMed 26817502 · doi:10.3945/ajcn.115.115188

• In 119 healthy UK adults aged 50 to 64, 12 weeks (2010). In a randomised, double-blind, placebo-controlled trial, participants took 50, 100 or 200 µg of selenium a day as selenium-enriched yeast tablets, or placebo tablets, or ate meals made with selenium-enriched onions (50 µg a day) or ordinary onions. Plasma selenium rose with each yeast dose, and selenoprotein P, which the authors call a useful marker of selenium status, rose in every selenium group, including the onion group. Platelet glutathione peroxidase activity did not change with any dose or form. The authors estimate that 50 µg a day on top of the participants’ usual intake of about 55 µg was needed to optimise selenoprotein P. The trial was funded by the UK Food Standards Agency, the Institute of Food Research and the US National Institutes of Health; the supplement maker Pharma Nord donated the tablets.

  Hurst R et al. (2010). Establishing optimal selenium status: results of a randomized, double-blind, placebo-controlled trial. American Journal of Clinical Nutrition. PubMed 20181815 · doi:10.3945/ajcn.2009.28169

Echinacea

A North American flowering plant used in herbal tradition for centuries. Found in: InsuLess, Liberate, Wellness Essentials.

• In 755 healthy adults, four months (2012). In a randomised, double-blind, placebo-controlled trial run at the Common Cold Centre at Cardiff University, an Echinacea purpurea extract (Echinaforce, an alcohol extract of the herb and root) was as well tolerated as placebo.

  Jawad M et al. (2012). Safety and efficacy profile of Echinacea purpurea to prevent common cold episodes: a randomized, double-blind, placebo-controlled trial. Evidence-Based Complementary and Alternative Medicine. PubMed 23024696 · doi:10.1155/2012/841315

• Cochrane review of 24 double-blind trials, 4,631 participants (2014). The trials compared single-herb echinacea preparations with placebo, with the common cold as the outcome. They used many different preparations, made from different species and parts of the plant, and the authors note that products sold as echinacea differ appreciably in composition. Drop-outs and reported adverse effects did not differ significantly between the echinacea and placebo groups, although prevention trials showed a trend towards more drop-outs due to adverse events with echinacea. Four of the six authors had worked on some of the included trials and did not extract or assess the data from those trials.

  Karsch-Völk M et al. (2014). Echinacea for preventing and treating the common cold. Cochrane Database of Systematic Reviews. PubMed 24554461 · doi:10.1002/14651858.CD000530.pub3

• Review of safety data on echinacea taken by mouth (2016). Pharmacognosy researchers at the University of Graz review drug interactions, contraindications, adverse events, length of use and use in pregnancy and breastfeeding. In studies in people, standardised Echinacea purpurea preparations did not significantly inhibit two drug-metabolising liver enzymes, CYP2D6 and CYP3A4, although laboratory studies using liver cell fractions gave conflicting results. Adverse events reported in clinical trials of single-herb preparations were generally mild, and studies of continuous use for up to six months reported no toxicological concerns. The authors stress that safety data are as specific to the product tested as efficacy data are.

  Ardjomand-Woelkart K, Bauer R (2016). Review and assessment of medicinal safety data of orally used Echinacea preparations. Planta Medica. PubMed 26441065 · doi:10.1055/s-0035-1558096

• In 80 Korean adults, eight weeks (2024). In a randomised, double-blind, placebo-controlled trial, participants took 200 mg a day of an Echinacea purpurea extract made with 60% ethanol, or a placebo. The trial measured natural killer cell activity and blood levels of three immune signalling proteins (IL-2, interferon-γ and TNF-α); those results are in the paper. Fatigue scores did not change, and the trial also recorded upper respiratory symptoms with a questionnaire. No adverse reactions were reported, and laboratory tests and vital signs showed no clinically significant changes. Four of the five authors work for the Korean company NUON Co., Ltd.

  Lee SK et al. (2024). A randomized, double-blind, placebo-controlled study on immune improvement effects of ethanolic extract of Echinacea purpurea (L.) Moench in Korean adults. Phytotherapy Research. PubMed 38743584 · doi:10.1002/ptr.8224

Lactoferrin

An iron-binding protein found in milk, colostrum, saliva and tears. Our Lactoferrin uses Bioferrin® from cow’s milk. Found in: Lactoferrin.

• Review of oral bovine lactoferrin (2020). Italy’s National Institute of Health summarises the research on lactoferrin taken by mouth: an iron-binding glycoprotein that forms part of the body’s innate defences, listed by the US FDA as generally recognised as safe.

  Superti F (2020). Lactoferrin from bovine milk: a protective companion for life. Nutrients. PubMed 32847014 · doi:10.3390/nu12092562

• Meta-analysis of six randomised trials, 1,194 participants (2021). The trials tested lactoferrin, with respiratory illness as the outcome. The authors call the evidence promising and call for larger, well-designed trials; one author sits on a lactoferrin product’s advisory board.

  Ali AS et al. (2021). Lactoferrin reduces the risk of respiratory tract infections: a meta-analysis of randomized controlled trials. Clinical Nutrition ESPEN. PubMed 34620326 · doi:10.1016/j.clnesp.2021.08.019

• Systematic review and meta-analysis of 25 studies, 2,329 participants (2022). Twenty of the studies were in adults, both healthy people and people with health conditions, and five were in healthy infants and children. The review looked at markers of inflammation, the numbers and activity of immune cells, and respiratory infections. Its pooled analyses of adult trials covered two inflammatory markers, IL-6 and C-reactive protein, and natural killer cell activity; many of those trials were in people with health conditions, such as women with iron deficiency or hereditary thrombophilia and adults with type 2 diabetes, and results varied widely between trials. The authors describe clinical studies of lactoferrin as limited and call for well-designed, adequately powered trials. It was supported by an Australian government grant in partnership with the food company Freedom Foods Group Nutritionals and the University of Newcastle; the authors report no conflicts of interest.

  Berthon BS et al. (2022). Effect of lactoferrin supplementation on inflammation, immune function, and prevention of respiratory tract infections in humans: a systematic review and meta-analysis. Advances in Nutrition. PubMed 35481594 · doi:10.1093/advances/nmac047

• In 157 healthy adults aged 18 to 38, 12 weeks (2023). In a randomised, double-blind, placebo-controlled trial at a Japanese university, participants licked and then swallowed tablets supplying 200 mg of bovine lactoferrin a day, or placebo tablets, and kept a diary of respiratory and general symptoms such as throat discomfort, runny nose and feeling feverish; 145 of them were included in the analysis. Blood samples taken at 12 weeks were tested for activation markers on plasmacytoid dendritic cells, a type of immune cell found in blood; those results are in the paper. Adverse events were similar in both groups. Morinaga Milk Industry funded the study and supplied the tablets, and five of the nine authors work for the company.

  Oda H et al. (2023). Effects of bovine lactoferrin on the maintenance of respiratory and systemic physical conditions in healthy adults-a randomized, double-blind, placebo-controlled trial. Nutrients. PubMed 37764743 · doi:10.3390/nu15183959

Modified citrus pectin

Fibre from citrus peel, broken into smaller pieces so it can be absorbed. Found in: Toxin Mobilization Binder.

• Review of preclinical and clinical research (2019). Describes how low-molecular-weight modified citrus pectin binds galectin-3, a protein studied in many laboratory and clinical models, and summarises the wider research. The lead author owns a supplement company.

  Eliaz I, Raz A (2019). Pleiotropic effects of modified citrus pectin. Nutrients. PubMed 31683865 · doi:10.3390/nu11112619

• In 68 adults with high blood pressure, six months (2021). In a randomised, double-blind, placebo-controlled trial in Boston, adults treated for high blood pressure who had raised blood levels of galectin-3 took modified citrus pectin (PectaSol-C), 4.8 g three times a day, or a placebo. Compared with placebo, the pectin did not change blood markers of collagen turnover, artery stiffness or heart function measured by ultrasound. More people stopped taking the pectin than the placebo because of digestive side effects, and 52 of the 68 completed the trial. The trial was funded by the US National Institutes of Health; EcoNugenics, which makes PectaSol-C, supplied the pectin and placebo.

  Lau ES et al. (2021). Galectin-3 Inhibition With Modified Citrus Pectin in Hypertension. JACC: Basic to Translational Science. PubMed 33532663 · doi:10.1016/j.jacbts.2020.10.006

Chlorella

A single-celled freshwater green alga, dried and eaten as a powder or in tablets. Found in: Toxin Mobilization Binder.

• Meta-analysis of 24 trials, 815 adults without chronic disease (2026). The trials, run in Japan, Iran, Korea, Taiwan and Germany and published between 1975 and 2024, had 8 to 52 participants each and gave 135 mg to 15 g of chlorella a day for 1 to 12 weeks; twelve of them combined chlorella with an exercise programme. They measured body weight and fat, blood pressure, blood fats, blood sugar control, liver enzymes, and inflammation and antioxidant markers. Pooled results showed changes in several markers, among them a fall in MDA, a marker of oxidative damage, and a rise in the antioxidant enzyme catalase. The reviewers rated all but two trials as poor quality and the certainty of the evidence as very low for most outcomes, and advise caution; few trials recorded side effects thoroughly.

  Mardani H et al. (2026). Beneficial effects of Chlorella species supplementation in the general population: a GRADE-assessed systematic review and dose-response meta-analysis. Nutrition & Diabetes. PubMed 42420253 · doi:10.1038/s41387-026-00449-3

• In 51 healthy Korean adults, eight weeks (2012). In a randomised, double-blind, placebo-controlled trial, participants took 5 g a day of Chlorella vulgaris tablets or a placebo; 51 of the 60 enrolled completed it. The trial measured the activity of natural killer cells, a type of white blood cell, and blood levels of immune messengers; those results are in the paper. No serious adverse reactions were reported. The trial was part-funded by Daesang, which made the tablets, and two of the authors were affiliated with the company.

  Kwak JH et al. (2012). Beneficial immunostimulatory effect of short-term Chlorella supplementation: enhancement of natural killer cell activity and early inflammatory response (randomized, double-blinded, placebo-controlled trial). Nutrition Journal. PubMed 22849818 · doi:10.1186/1475-2891-11-53

Sulforaphane (BroccoPhane® broccoli seed)

The best-known compound in broccoli, stored in the plant as glucoraphanin. Found in: Toxin Mobilization Binder.

• Review of more than 50 human trials and animal studies (2019). Researchers from Johns Hopkins, Dundee and the Fred Hutchinson Cancer Research Center explain how the source (plants, sprouts, drinks or supplements), form and dose of sulforaphane decide how much of it the body actually receives.

  Yagishita Y et al. (2019). Broccoli or sulforaphane: is it the source or dose that matters? Molecules. PubMed 31590459 · doi:10.3390/molecules24193593

• In 170 people in Qidong, China, ten days (2019). In a randomised, placebo-controlled trial, participants drank a placebo or a broccoli sprout drink at full, half or one-fifth strength every day for ten days. Only the full-strength drink, which led to about 25 µmol of sulforaphane metabolites in the urine a day, significantly raised the amount of benzene, an air pollutant, passed in the urine bound to glutathione, by 63.2%; the weaker drinks did not differ from placebo. The trial was funded by the US National Cancer Institute.

  Chen JG et al. (2019). Dose-dependent detoxication of the airborne pollutant benzene in a randomized trial of broccoli sprout beverage in Qidong, China. American Journal of Clinical Nutrition. PubMed 31268126 · doi:10.1093/ajcn/nqz122

• In 49 adults who smoke, randomised crossover, two weeks per dose (2022). In an open-label trial, otherwise healthy heavy smokers took broccoli seed and sprout extract tablets (Avmacol®) supplying 148 or 296 µmol of glucoraphanin a day, two weeks at each dose in random order with a two-week break between. At the higher dose, the amounts of three chemicals in tobacco smoke (benzene, acrolein and crotonaldehyde) passed in the urine bound to glutathione rose significantly. About 10–11% of the glucoraphanin was recovered in urine as sulforaphane metabolites. Twenty-nine participants reported mild digestive side effects such as loose stools, none of them severe. The trial was funded by the US National Cancer Institute; Nutramax Laboratories, which makes the tablets, supplied them.

  Bauman JE et al. (2022). Randomized Crossover Trial Evaluating Detoxification of Tobacco Carcinogens by Broccoli Seed and Sprout Extract in Current Smokers. Cancers. PubMed 35565256 · doi:10.3390/cancers14092129

Milk thistle (silymarin)

Silymarin is the mix of plant compounds, led by silybin, extracted from the seeds of the milk thistle, Silybum marianum. Found in: Toxin Mobilization Binder.

• Cochrane review of 17 randomised trials, 2,069 adults (2025). The trials, lasting 4 to 48 weeks, tested silymarin alone or in complexes with substances such as vitamin E or phosphatidylcholine, in adults with fatty liver disease linked to metabolic dysfunction (MASLD). The review looked at side effects, liver enzymes, deaths and quality of life; one trial reported serious adverse events, none judged related to the treatment, and no trial reported deaths or quality of life. The reviewers rate the certainty of the evidence low to very low and call for well-designed trials. The review had no dedicated funding.

  Wang C et al. (2025). Silymarin for adults with metabolic dysfunction-associated steatotic liver disease. Cochrane Database of Systematic Reviews. PubMed 40552569 · doi:10.1002/14651858.CD015524.pub2

• Systematic review of pharmacokinetic studies (2021). Researchers at Charles University and the Czech Academy of Sciences reviewed how the flavonolignans in silymarin are absorbed and cleared. Taken by mouth, they are quickly bound to other molecules (conjugated) in the gut wall and liver and pumped back into the gut and bile, so little of the unchanged compounds reaches the blood at common doses; only about 1–5% of a dose leaves through the kidneys. Most human studies found no interactions with medicines of the kind laboratory tests had suggested.

  Tvrdý V et al. (2021). Systematic review of pharmacokinetics and potential pharmacokinetic interactions of flavonolignans from silymarin. Medicinal Research Reviews. PubMed 33587317 · doi:10.1002/med.21791

• In 17 healthy men, two-week crossover (2021). In a randomised, single-blind, placebo-controlled crossover trial at Griffith University in Australia, men aged 18 to 65 took silymarin (Legalon®), 140 mg three times a day, and a placebo for 14 days each, at least four weeks apart. Silymarin did not change blood levels of bilirubin, cholesterol, triglycerides or C-reactive protein, or the blood’s antioxidant capacity.

  Vidimce J et al. (2021). Effect of Silymarin Treatment on Circulating Bilirubin and Cardiovascular Disease Risk Factors in Healthy Men: A Single-Blind, Randomized Crossover Trial. Clinical Pharmacology in Drug Development. PubMed 34242497 · doi:10.1002/cpdd.962

Curcumin and piperine

Curcumin is the golden compound in turmeric; piperine comes from black pepper. Found in: Toxin Mobilization Binder, Liberate.

• In rats and healthy human volunteers (1998). Curcumin alone was barely detectable in the blood. Taken with 20 mg of piperine, its bioavailability rose by 2,000% in people, with no adverse effects.

  Shoba G et al. (1998). Influence of piperine on the pharmacokinetics of curcumin in animals and human volunteers. Planta Medica. PubMed 9619120 · doi:10.1055/s-2006-957450

• Meta-analysis of 66 randomised trials in adults (2023). Pools trials of turmeric or curcumin supplements that measured blood markers of inflammation (CRP, TNF-α, IL-6 and IL-1β) and of oxidative stress (total antioxidant capacity, the enzyme SOD, and MDA, a marker of oxidative damage to fats); the results are in the paper.

  Dehzad MJ et al. (2023). Antioxidant and anti-inflammatory effects of curcumin/turmeric supplementation in adults: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials. Cytokine. PubMed 36804260 · doi:10.1016/j.cyto.2023.156144

• In 30 healthy adults, single doses, crossover (2021). In a randomised, open-label study, volunteers aged 18 to 45 took single doses of five turmeric products at their recommended amounts, including 1,500 mg of a 95% curcuminoid extract with 15 mg of BioPerine® piperine. Blood levels of total curcuminoids after this piperine combination did not differ significantly from those after a plain 95% extract; per milligram, a micellar liquid and a dried colloidal form gave higher levels than the plain extract. The study was funded by Naturex, which makes the plain extract and the colloidal form, and four of the authors worked for it.

  Fança-Berthon P et al. (2021). Pharmacokinetics of a Single Dose of Turmeric Curcuminoids Depends on Formulation: Results of a Human Crossover Study. Journal of Nutrition. PubMed 33877323 · doi:10.1093/jn/nxab087

White willow bark

A traditional source of salicin, the plant compound that inspired aspirin. Found in: Liberate.

• Systematic review of clinical trials (2009). The trials, run in people with back and joint pain, used ethanolic willow bark extracts supplying up to 240 mg salicin a day for up to six weeks; minor adverse events were reported. Willow bark is not suitable for people sensitive to aspirin or salicylates.

  Vlachojannis JE, Cameron M, Chrubasik S (2009). A systematic review on the effectiveness of willow bark for musculoskeletal pain. Phytotherapy Research. PubMed 19140170 · doi:10.1002/ptr.2747

• Safety review by the United States Pharmacopeia (2019). Trials of willow bark extracts supplying 120–240 mg of salicin a day for up to eight weeks, all in adults, reported no serious adverse effects; the most common were digestive, with a few allergic reactions. The reviewers note a risk of bleeding in vulnerable people and of reactions in people sensitive to aspirin, and that 240 mg of salicin could yield 113 mg of salicylic acid, more than the 62 mg from an 81 mg low-dose aspirin. The USP monograph now says willow bark products should be labelled as not for children, pregnant or breastfeeding women, or people sensitive to aspirin.

  Oketch-Rabah HA et al. (2019). United States Pharmacopeia Safety Review of Willow Bark. Planta Medica. PubMed 31604354 · doi:10.1055/a-1007-5206

Boswellia serrata

The gum resin of the Indian frankincense tree, used in Ayurvedic tradition and rich in boswellic acids. Found in: Liberate.

• Meta-analysis of 13 randomised trials in people with knee osteoarthritis (2024). Researchers at the University of Bologna pooled trials of extracts from Boswellia gum resin, given alone or with other plant extracts, measuring symptoms with the WOMAC questionnaire (850 patients) and pain scales (1,185 patients). The trials differed widely; the authors call for further high-quality studies and note that data on side effects are still incomplete. The review received no specific funding.

  Dalmonte T et al. (2024). Efficacy of Extracts of Oleogum Resin of Boswellia in the Treatment of Knee Osteoarthritis: A Systematic Review and Meta-Analysis. Phytotherapy Research. PubMed 39314013 · doi:10.1002/ptr.8336

• In 20 healthy volunteers, single doses, crossover (2024). Researchers at Ulm University gave volunteers 800 mg of a standard Boswellia serrata dry extract and, on another occasion, 800 mg of a micellar (water-dispersible) form. The amounts of boswellic and lupeolic acids reaching the blood were about 17 to 43 times higher after the micellar form. Blood taken after each product was also stimulated in the laboratory to measure its release of the inflammatory messenger TNF-α; that result is in the paper.

  Schmiech M et al. (2024). Single-dose comparative pharmacokinetic/pharmacodynamic study of a micellar formulation versus a native Boswellia serrata dry extract in healthy volunteers. Phytomedicine. PubMed 39033725 · doi:10.1016/j.phymed.2024.155863

Ashwagandha

The root of Withania somnifera, an adaptogenic herb of Ayurvedic tradition. Found in: Liberate, Wellness Essentials.

• In 60 stressed but healthy adults, eight weeks (2019). Ashwagandha root extract at 250 or 600 mg a day lowered perceived-stress scores and serum cortisol compared with placebo, and participants reported better sleep quality. The extract (KSM-66) was supplied by its maker, Ixoreal Biomed.

  Salve J et al. (2019). Adaptogenic and anxiolytic effects of ashwagandha root extract in healthy adults: a double-blind, randomized, placebo-controlled clinical study. Cureus. PubMed 32021735 · doi:10.7759/cureus.6466

• In 60 adults with insomnia and anxiety, ten weeks (2019). A randomised, double-blind, placebo-controlled trial of ashwagandha root extract, 300 mg twice daily, measuring sleep onset, sleep efficiency and sleep quality with sleep actigraphy and questionnaires. The authors call for larger studies. The extract (KSM-66) is made by Ixoreal Biomed.

  Langade D et al. (2019). Efficacy and safety of ashwagandha (Withania somnifera) root extract in insomnia and anxiety: a double-blind, randomized, placebo-controlled study. Cureus. PubMed 31728244 · doi:10.7759/cureus.5797

• Meta-analysis of 23 randomised trials, 1,706 adults (2026). Pooled placebo-controlled trials of ashwagandha taken by mouth that measured hormone levels. Compared with placebo, ashwagandha lowered cortisol and raised serotonin. It made no difference to thyroid-stimulating hormone (TSH) or T3, while T4 rose modestly. Testosterone rose in men but not in women, and oestradiol did not change in either. The authors note wide differences between trials and limited data for some hormones.

  Fornalik M et al. (2026). Hormonal modulation with Withania somnifera: systematic review and meta-analysis of randomized-controlled trials. Planta Medica. PubMed 41740946 · doi:10.1055/a-2802-8363

• Meta-analysis of 13 randomised trials, 599 participants (2026). The trials, mainly in young adults and athletes, compared ashwagandha with placebo or a control on objective tests of exercise performance. On average ashwagandha improved performance (moderate-certainty evidence), most clearly aerobic endurance; effects on strength were positive but uncertain. The likely range for future trials included no benefit, so the authors say the effect is not consistent across settings, and 12 of the 13 trials were judged at some or high risk of bias. Dose analyses were exploratory; 500–600 mg of extract a day was the range with most evidence behind it.

  Li X et al. (2026). Effects of Withania somnifera (ashwagandha) supplementation on exercise performance: a systematic review and three-level meta-analysis. Nutrients. PubMed 42356302 · doi:10.3390/nu18121915

• Case series of five people in Iceland and the US (2020). Describes five adults aged 21 to 62 whose liver injury was attributed, after other causes were excluded, to supplements containing ashwagandha, at label doses of 450 to 1,350 mg a day. Jaundice, with symptoms such as nausea, tiredness and itching, began 2 to 12 weeks after they started taking them. Chemical analysis confirmed ashwagandha in the supplements available for testing and found no other toxic compounds; four of the five were also taking other supplements, and in one case rhodiola may also have played a part. The work was funded by the US National Institutes of Health.

  Björnsson HK et al. (2020). Ashwagandha-induced liver injury: a case series from Iceland and the US Drug-Induced Liver Injury Network. Liver International. PubMed 31991029 · doi:10.1111/liv.14393

Wild blueberry

Rich in anthocyanins, the pigments that give blueberries their colour. Found in: Wellness Essentials.

• In nine older adults with early memory changes, 12 weeks (2010). A small pilot study of daily wild blueberry juice, assessing memory with paired-associate learning and word-list recall tests. The authors call for larger trials. The blueberry juice was provided by the Wild Blueberry Association of North America.

  Krikorian R et al. (2010). Blueberry supplementation improves memory in older adults. Journal of Agricultural and Food Chemistry. PubMed 20047325 · doi:10.1021/jf9029332

• Meta-analysis of 14 randomised trials, 632 healthy participants (2026). Blueberry intake improved flow-mediated dilation, a measure of how well arteries widen, by 1.11% compared with control. It made no significant difference to systolic or diastolic blood pressure, executive function or mood. The authors point to differences in dose, form, trial length and participants’ ages between trials, and call for larger trials with standard methods.

  He Y et al. (2026). Blueberry consumption enhances vascular function but not cognitive abilities in healthy individuals: a systematic review and meta-analysis. Nutrition Research. PubMed 41974068 · doi:10.1016/j.nutres.2026.03.007

• In 61 healthy adults aged 65 to 80, 12 weeks (2023). In a double-blind randomised trial, 26 g a day of freeze-dried wild blueberry powder (302 mg anthocyanins, equal to 178 g of fresh berries) improved flow-mediated dilation, a measure of how well arteries widen, and lowered 24-hour systolic blood pressure by 3.59 mmHg compared with placebo. Cognitive results were mixed: immediate word recall and task-switching accuracy were better with blueberry, delayed recall with placebo. A 2025 correction revised the baseline table and reanalysed the task-switching result, which stayed significant. The Wild Blueberry Association of North America funded the study and gave the powder, with no say in its design or analysis.

  Wood E et al. (2023). Wild blueberry (poly)phenols can improve vascular function and cognitive performance in healthy older individuals: a double-blind randomized controlled trial. American Journal of Clinical Nutrition. PubMed 36972800 · doi:10.1016/j.ajcnut.2023.03.017

• In 122 adults aged 65 to 80, six months (2018). Healthy older volunteers with self-reported memory complaints took placebo, a wild blueberry powder (500 or 1,000 mg a day) or a purified wild blueberry extract (111 mg a day) in a randomised, double-blind trial. The extract group did better than placebo on delayed word recognition at three months but not at six, and over the study its systolic blood pressure was lower than with placebo (116 against 122 mmHg). The powders showed no such effects, and working memory, executive function and mood did not differ. Naturex, which makes the extract and powders, funded the study and helped design it and write the paper.

  Whyte AR et al. (2018). A randomized, double-blinded, placebo-controlled study to compare the safety and efficacy of low dose enhanced wild blueberry powder and wild blueberry extract (ThinkBlue™) in maintenance of episodic and working memory in older adults. Nutrients. PubMed 29882843 · doi:10.3390/nu10060660

Shilajit

A mineral-rich resin from high mountain rock, used in Ayurveda. Found in: Wellness Essentials.

• In healthy men aged 45–55, 90 days (2016). Purified shilajit, 250 mg twice a day, raised total and free testosterone and DHEAS compared with placebo in a randomised, double-blind trial.

  Pandit S et al. (2016). Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia. PubMed 26395129 · doi:10.1111/and.12482

• In 63 young, recreationally active men, eight weeks (2019). A double-blind trial randomised the men to purified shilajit (PrimaVie) at 250 or 500 mg a day, or placebo. Among the stronger half, the 500 mg group lost less strength in a fatiguing leg-extension test than the 250 mg and placebo groups (8.9% against 17.0% and 16.0%); across all 63 men it differed only from the 250 mg group. In men with higher starting hydroxyproline, a marker of collagen breakdown, levels after 500 mg were lower than after 250 mg or placebo; across all 63 men they did not differ. Natreon, which makes PrimaVie, funded the study.

  Keller JL et al. (2019). The effects of Shilajit supplementation on fatigue-induced decreases in muscular strength and serum hydroxyproline levels. Journal of the International Society of Sports Nutrition. PubMed 30728074 · doi:10.1186/s12970-019-0270-2

• In 45 healthy women aged 30 to 65, 14 weeks (2019). The women were randomised to placebo or to purified shilajit (PrimaVie) at 125 or 250 mg twice a day. In skin biopsies taken at weeks 2 and 14, the higher dose raised the activity of genes linked to the skin’s supporting matrix compared with placebo, and of genes linked to blood-vessel growth compared with week 2. At that dose, blood flow in the skin’s small vessels, judged from the colour of skin images, improved compared with placebo; skin hydration, elasticity and barrier function did not differ. No adverse effects were reported. The work was funded partly by a US National Institutes of Health grant and partly by Natreon, which makes PrimaVie and supplied the capsules.

  Das A et al. (2019). Skin transcriptome of middle-aged women supplemented with natural herbo-mineral shilajit shows induction of microvascular and extracellular matrix mechanisms. Journal of the American College of Nutrition. PubMed 31161927 · doi:10.1080/07315724.2018.1564088

• Review of published analyses of shilajit (2024). Brings together published data on the metals reported in shilajit: around 65, including toxic ones such as lead, arsenic, cadmium and mercury. In most studies the reported levels were below World Health Organization and US Food and Drug Administration limits for herbal medicines, but a few studies found levels above them. The authors conclude that taking shilajit without knowing its metal content is not safe.

  Hussain A, Saeed A (2024). Hazardous or advantageous: uncovering the roles of heavy metals and humic substances in shilajit (phyto-mineral) with emphasis on heavy metals toxicity and their detoxification mechanisms. Biological Trace Element Research. PubMed 38393486 · doi:10.1007/s12011-024-04109-4

Fasting, sleep and physical activity

The studies behind our lifestyle guides: Fasting and electrolytes, Sleep, movement and recovery and How to build a daily supplement routine.

• Review (2019). Covers intermittent fasting research in animals and people, including the switch from glucose to ketones that fasting triggers.

  de Cabo R, Mattson MP (2019). Effects of intermittent fasting on health, aging, and disease. New England Journal of Medicine. PubMed 31881139 · doi:10.1056/NEJMra1905136

• Review (2018). Reviews the body’s responses to the “metabolic switch”: the point, typically between 12 and 36 hours after the last meal and depending on liver glycogen and activity, at which fat and ketones become the main fuel.

  Anton SD et al. (2018). Flipping the metabolic switch: understanding and applying the health benefits of fasting. Obesity. PubMed 29086496 · doi:10.1002/oby.22065

• Review (2014). Summarises the molecular mechanisms of fasting studied in model organisms and people.

  Longo VD, Mattson MP (2014). Fasting: molecular mechanisms and clinical applications. Cell Metabolism. PubMed 24440038 · doi:10.1016/j.cmet.2013.12.008

• In mice (2010). Short-term fasting markedly increased autophagy (the cell’s recycling process) in neurons. This was a mouse study, so it does not show what happens in people.

  Alirezaei M et al. (2010). Short-term fasting induces profound neuronal autophagy. Autophagy. PubMed 20534972 · doi:10.4161/auto.6.6.12376

• In 1,422 adults at a German fasting clinic (2019). In an observational study of medically supervised Buchinger fasting (200–250 kcal a day for 4 to 21 days), adverse effects were reported by fewer than 1% of participants, and well-being scores rose. Four of the five authors have, or had, a role at the clinic as director, employee or consultant.

  Wilhelmi de Toledo F et al. (2019). Safety, health improvement and well-being during a 4 to 21-day fasting period in an observational study including 1422 subjects. PLoS One. PubMed 30601864 · doi:10.1371/journal.pone.0209353

• Consensus statement (2015). The American Academy of Sleep Medicine and Sleep Research Society recommend that adults aged 18 to 60 sleep at least seven hours a night on a regular basis.

  Watson NF et al. (2015). Recommended amount of sleep for a healthy adult: a joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. Sleep. PubMed 26039963 · doi:10.5665/sleep.4716

• World Health Organization guidelines (2020). Adults should do 150–300 minutes of moderate or 75–150 minutes of vigorous aerobic activity a week, plus muscle-strengthening activity on two or more days.

  Bull FC et al. (2020). World Health Organization 2020 guidelines on physical activity and sedentary behaviour. British Journal of Sports Medicine. PubMed 33239350 · doi:10.1136/bjsports-2020-102955

• In 12 healthy middle-aged men, an eight-day water-only fast (2021). The men, all experienced fasters, drank only mineral water for eight days, with blood and 24-hour urine tested before and after. Average blood sodium fell from 139.25 to 133.83 mmol/L, below the reference range of 136–146 mmol/L; blood calcium and magnesium also fell, and the kidneys excreted less sodium and potassium. Blood uric acid more than doubled, and blood glucose fell. The authors conclude that the men remained safe over the eight days but that continuing the fast would have been detrimental, and caution that so small a group cannot be generalised.

  Ogłodek E, Pilis W (2021). Is water-only fasting safe? Global Advances in Health and Medicine. PubMed 34414015 · doi:10.1177/21649561211031178

• Chart review of 768 water-only fasts at a US medical centre (2018). Records of 652 adults who fasted on water alone under medical supervision at a residential centre in Santa Rosa, California, from 2007 to 2011 were reviewed for adverse events. Fasts lasted 2 to 41 days (median seven). Of the adverse events, 75% were mild, and most were known reactions to fasting; in 212 visits the most serious event was graded severe, and in one it was life-threatening. Two stays involved a serious event needing hospital care: dehydration on day 3 of one fast and low blood sodium on day 9 of another. The centre’s foundation helped fund the study, and the centre’s director and two paid consultants to its foundation are among the authors.

  Finnell JS et al. (2018). Is fasting safe? A chart review of adverse events during medically supervised, water-only fasting. BMC Complementary and Alternative Medicine. PubMed 29458369 · doi:10.1186/s12906-018-2136-6

• Cochrane review of 22 randomised trials, 1,995 adults (2026). Pooled trials of intermittent fasting, including time-restricted eating and alternate-day and periodic fasting, in adults with overweight or obesity; each lasted at least four weeks with at least six months’ follow-up. Compared with regular dietary advice, intermittent fasting may make little or no difference to weight loss or quality of life (low-certainty evidence), and the evidence on adverse events is very uncertain. The trials followed people for up to 12 months, and the authors call for longer studies.

  Garegnani LI et al. (2026). Intermittent fasting for adults with overweight or obesity. Cochrane Database of Systematic Reviews. PubMed 41692034 · doi:10.1002/14651858.CD015610.pub2

How we choose and check studies

We list peer-reviewed studies indexed on PubMed, open each one, and summarise only what its abstract or full text reports, including who was studied and any conflict of interest the authors declare. Every citation was re-checked on 20 October 2026 against its PubMed record, its DOI registration and, where freely available, the full paper. Where a study measured illness, immune or inflammation markers, or lifespan, we say who was studied and what was measured and leave the results to the paper: UK law allows food supplements only approved health claims, and none may claim to prevent or treat illness. If you know of a study we should add, or a summary that could be clearer, please send us a message. Library reviewed 20 October 2026.

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