Supplements

WHAT THE EVIDENCE SAYS

The decisive study for this entry is MISTRAL (Palliative Medicine, July 2026): a phase 3, multicentre, randomised, double-blind, placebo-controlled trial in which 290 patients with advanced pancreatic cancer received standard treatment plus either subcutaneous mistletoe extract or placebo ^[1]. The primary focus was health-related quality of life, measured with the EORTC QLQ-C30 and QLQ-PAN26 questionnaires ^[1]. The result: no statistically significant differences between the arms in either quality of life or body weight ^[1]. In the nested biomarker study, the only significant change was a rise in eosinophils in the mistletoe group, with no clinical correlate; there were no differences in blood counts, lymphocyte subpopulations, C-reactive protein, albumin or Ca19-9 ^[1]. The authors' conclusion, verbatim: "Since no benefit was observed, there is no clinical reason to recommend mistletoe extract in patients with advanced pancreatic cancer ^[1]."

WHY WE PUT THIS SO PLAINLY WHEN OTHER SOURCES READ DIFFERENTLY.

This is a point where two credible sources diverge, and readers deserve to know what the difference rests on. The National Cancer Institute summary reports older work with mixed results: in pancreatic cancer, longer survival was described in people given mistletoe extract; in melanoma there was no increase in survival time; in lung cancer no differences were found ^[2]. We do not settle the contradiction by picking the more convenient sentence, but on methodological grounds. The earlier studies suggesting benefit in pancreatic cancer were neither blinded nor placebo-controlled, and in quality-of-life research that is decisive: a patient who knows they are receiving an "extra treatment" rates how they feel differently from one who does not ^[2]. MISTRAL tested precisely the setting in which the earlier data looked most promising, in a design immune to that effect, and found no benefit ^[1].

STRENGTH OF THE EVIDENCE

Moderate for the topic as a whole, high for one specific question. High: adding mistletoe to standard treatment in advanced pancreatic cancer does not improve quality of life — that comes from a large trial with the strongest available design ^[1]. Moderate for the rest: mistletoe preparations differ from one another (host tree species, manufacturer, method of preparation), they are used across many diagnoses and schedules, and most remaining data come from unblinded, small or observational studies ^[2]. This must not be read as "absence of effect has been proven in every cancer"; the correct statement is that where it has been tested most rigorously no benefit was shown, and elsewhere high-quality evidence is lacking.

WHAT READERS MAY NOT KNOW ABOUT HOW IT IS GIVEN.

Mistletoe in oncology is usually not a tablet or a tea. According to the National Cancer Institute, extracts are most often given by injection under the skin, and less commonly by mouth, into a vein, into the pleural cavity, or directly into a tumour ^[2]. This has two practical consequences. First, it is not a "dietary supplement" in the everyday sense and should not be thought of like a vitamin from the pharmacy. Second, reported side effects include soreness and inflammation at injection sites, headache, fever, chills, nausea and severe tiredness, and a few cases of severe allergic reactions, including anaphylactic shock, have been reported ^[2].

INTERACTIONS WITH CANCER TREATMENT

In the reference sources available to us there is no documented pharmacokinetic interaction between mistletoe and any specific anticancer drug — and we say so plainly rather than implying an interaction that has not been demonstrated ^[2][3]. The real problems lie elsewhere, and there are three.

• Fever, chills and injection-site inflammation can be mistaken for signs of infection. In a patient undergoing chemotherapy, particularly during neutropenia, fever is a state requiring urgent medical assessment — and a preparation that itself causes fever blurs that signal.
• Mistletoe extracts are immunologically active (MISTRAL recorded a rise in eosinophils) ^[1]. Data on combining them with modern immunotherapy, including checkpoint inhibitors, simply do not exist. Absence of data is not evidence of safety and should not be read as such.
• The risk of a severe allergic reaction, though rare, is real and independent of the cancer itself ^[2].

The general rule the National Cancer Institute states without exceptions: tell your doctor about every preparation you are taking, including those regarded as natural and safe ^[3].

THE SCOPE OF WHAT WE WRITE HERE

We give no doses, brand names or administration schedules, and we do not decide whether any individual should stop or continue mistletoe — that is a decision for their treating team, and cancer3.ai is an information portal, not a clinic. We describe the state of knowledge: what has been tested, how strong the test was, and what it showed.

Sources

1. Wode K et al. — Mistletoe extract in patients with advanced pancreatic cancer: Health-related quality of life in a double-blind, randomized, placebo-controlled trial (MISTRAL), Palliative Medicine 2026: europepmc.org ↗
2. National Cancer Institute — Mistletoe Extracts (PDQ®), Patient Version, updated 2023: cancer.gov ↗
3. National Cancer Institute — Complementary and Alternative Medicine (CAM), updated 2024: cancer.gov ↗

WHERE THE PROBLEM CAME FROM

Soy isoflavones (mainly genistein and daidzein) are structurally similar to oestrogens and weakly stimulate oestrogen receptors. Because most breast cancers are hormone-dependent, patients were for years advised against soy, and many women still avoid it. These concerns rested on cell-line and animal studies in which genistein abolished the inhibitory effect of tamoxifen on tumour growth ^[3].

WHAT PATIENT DATA SHOW

• a pooled analysis of four cohorts (two US, two Chinese), 9,514 patients, mean follow-up 7.4 years, 1,348 recurrences and 1,171 deaths, including 881 from breast cancer ^[1];
• intake of at least 10 mg of isoflavones per day versus the lowest intake: recurrence HR 0.75 (95% CI 0.61-0.92);
• death from breast cancer HR 0.83 (95% CI 0.64-1.07) - a favourable direction, but not significant;
• death from any cause HR 0.87 (95% CI 0.70-1.10) - also not significant;
• a 2025 review of the clinical and epidemiological evidence concludes that post-diagnosis isoflavone intake from food reduces the risk of recurrence and that observational data do NOT indicate interference with the efficacy of tamoxifen or aromatase inhibitors ^[2].

WHAT THESE RESULTS DO NOT SAY

All of the above come from observational studies, not randomised trials - they show an association, not causation. Women who eat a lot of soy may differ from others in lifestyle, body weight and access to care, and the analyses adjust only for what was measured. Only the recurrence result was statistically significant; these data do not settle the question of overall survival. Nor do the results say that soy treats breast cancer or that intake should be increased beyond customary amounts.

FOOD IS NOT THE SAME AS A SUPPLEMENT

The doses in the cited studies correspond to an ordinary diet (10 mg of isoflavones is roughly one serving of tofu, soy milk or edamame); the 2025 review speaks of at most two servings of traditional soy foods per day, about 50 mg of isoflavones ^[2]. Isoflavone preparations deliver many times higher doses in isolated form, for which safety data in breast cancer patients are lacking. Memorial Sloan Kettering puts it as follows: soy in food form is generally safe, whereas supplements or larger amounts of soy should be discussed with the treating team ^[3]. This is the same principle that applies to beta-carotene: the safety of a compound in vegetables does not transfer automatically to a tablet.

INTERACTIONS WITH CANCER TREATMENT

• tamoxifen - the signal of weakened activity comes from preclinical models (genistein abolishes growth inhibition of MCF-7 cells); the clinical relevance remains unknown and patient data do not confirm it ^[2][3];
• aromatase inhibitors - observational data do not indicate reduced efficacy ^[2];
• high-dose isoflavone supplements - MSKCC classes the use of soy in hormone-sensitive cancers as a controversial question and advises talking to a doctor before taking a preparation ^[3];
• separate issues are soy allergy and the effect of large amounts of soy on levothyroxine absorption - these are general medical, not oncological, questions.

WHAT THIS MEANS FOR THE READER

There is no basis today for a woman with breast cancer to eliminate ordinary soy foods from her diet for fear of recurrence - the data point rather in the opposite direction. Taking concentrated isoflavone preparations is not justified. Any supplementation during hormone therapy is a decision for the doctor leading the treatment.

Sources

1. [1] Nechuta SJ i wsp. — Soy food intake after diagnosis of breast cancer and survival: an in-depth analysis of combined evidence from cohort studies of US and Chinese women, Am J Clin Nutr 2012 (n=9514, PMID 22648714): europepmc.org ↗
2. [2] Messina M, Nechuta S — A Review of the Clinical and Epidemiologic Evidence Relevant to the Impact of Postdiagnosis Isoflavone Intake on Breast Cancer Outcomes, Curr Nutr Rep 2025 (PMID 40131602): europepmc.org ↗
3. [3] Memorial Sloan Kettering Cancer Center — About Herbs: Soy (przegląd dowodów, interakcje z tamoksyfenem, ostrzeżenia): mskcc.org ↗

WHAT THE LARGEST TRIAL SHOWED

• a multicentre double-blind trial conducted in the URCC CCOP network; 576 patients entered the analysis (91% women, mean age 53) ^[1];
• patients were randomised to placebo or ginger at 0.5 g, 1.0 g or 1.5 g daily; the preparation was taken for 6 days, starting 3 days BEFORE chemotherapy ^[1];
• all participants received standard antiemetic treatment with a 5-HT3 receptor antagonist - ginger was studied as an ADDITION, never as a replacement ^[1];
• all ginger doses significantly reduced the severity of acute nausea on day 1 of chemotherapy compared with placebo (p=0.003); the largest reductions were at 0.5 g and 1.0 g (p=0.017 and p=0.036 respectively) ^[1];
• anticipatory nausea, arising before the drug was given, was an independent predictor of nausea (p<0.0001) ^[1].

STRENGTH OF EVIDENCE - MODERATE

MSKCC summarises the literature as mixed but generally supportive: ginger may reduce nausea and vomiting, while a systematic review pointed to the need for further confirmation and some studies showed no additional benefit when standard antiemetics were already in use ^[2]. The result is therefore not uniform: one large positive trial alongside a set of smaller studies with divergent outcomes.

WHAT THESE DATA DO NOT COVER

• the trial assessed ACUTE nausea on day 1; it is not evidence of efficacy in delayed nausea or in vomiting;
• the study population was 91% women and the abstract gives no breakdown by diagnosis, so transferring the result to any given cancer is extrapolation;
• there are no data here on any effect of ginger on the course of cancer, the efficacy of chemotherapy or survival.

INTERACTIONS AND SAFETY - THIS IS THE MOST IMPORTANT PART:

• BLEEDING: ginger inhibits thromboxane formation and platelet aggregation, and so significantly increases bleeding risk in people taking anticoagulant and antiplatelet drugs, including warfarin ^[2]. A fatal bleeding event has been reported in an elderly patient taking dabigatran after consuming a ginger and cinnamon mixture ^[2];
• SURGERY: because of bleeding risk, MSKCC advises stopping ginger 2 weeks before an operation ^[2];
• BLEEDING DISORDERS: a contraindication to use ^[2];
• OTHER DRUGS: potential interactions are described with non-steroidal anti-inflammatory drugs, insulin and tacrolimus ^[2];
• ADVERSE EFFECTS: most commonly heartburn and skin irritation ^[2];
• PREGNANCY: MSKCC advises avoiding it ^[2].

THE SCOPE OF WHAT WE WRITE HERE

We give the doses that WERE STUDIED, because they are part of describing the trial - this is not a dosing recommendation for an individual. Patients undergoing cancer treatment very often take anticoagulants (prophylaxis and treatment of venous thromboembolism is typical in oncology, not exceptional), have thrombocytopenia after chemotherapy, or are being prepared for surgery - in each of those situations the bleeding risk described above is real. Whether to take any plant preparation during treatment is decided by the treating physician, who should be told about ALL supplements being taken. This page describes the state of knowledge and is not advice for any individual.

Sources

1. [1] Ryan JL i wsp. — Ginger (Zingiber officinale) reduces acute chemotherapy-induced nausea: a URCC CCOP study of 576 patients, Supportive Care in Cancer 2012 (PMID 21818642): europepmc.org ↗
2. [2] Memorial Sloan Kettering Cancer Center — About Herbs: Ginger (podsumowanie kliniczne, działania niepożądane, interakcje z lekami przeciwkrzepliwymi): mskcc.org ↗

WHY PATIENTS REACH FOR IT

Sleep disturbance is among the most common and most overlooked problems in cancer - it accompanies treatment, anxiety, pain and hospital stays. Melatonin is available without prescription and widely assumed to be harmless, so it is often taken without the treating team knowing. That is precisely why this entry exists.

WHAT THE EVIDENCE SHOWS

• sleep and quality of life: in women after breast cancer treatment short-term supplementation improved sleep quality; improvement in subjective sleep quality has also been described in other patient groups ^[1];
• treatment side effects: data suggest a possible reduction in the incidence of thrombocytopenia, asthenia and neurotoxicity after chemotherapy, and of oral mucositis caused by chemo- and radiotherapy ^[1];
• fatigue, anxiety and mood: benefits have been described ^[1];
• survival: some trials report improvements in fatigue, quality of life and survival time, but the data are CONFLICTING and other work finds no benefit ^[1]. This point matters most here: melatonin is not to be treated as anticancer therapy.

STRENGTH OF EVIDENCE - MODERATE AND UNEVEN

The source's wording is consistently cautious (data suggest, has been described), and on survival it speaks explicitly of conflicting data ^[1]. Melatonin therefore stands as a supportive preparation of uncertain effect size, not an established part of supportive care.

ADVERSE EFFECTS

Drowsiness, headaches, altered mental status, tachycardia, hypothermia ^[1]. Driving should be avoided until the individual response is known ^[1]. A SEPARATE PAEDIATRIC WARNING: in children under 3 years, trouble breathing and deaths have been reported, and serious outcomes have been described in ingestion cases ^[1].

INTERACTIONS WITH TREATMENT - THE PART THAT MUST NOT BE OMITTED:

• HORMONE-SENSITIVE CANCERS: MSKCC lists breast and prostate cancer as a contraindication, because melatonin can change the amount of oestrogen in the body ^[1];
• ANTICOAGULANTS: melatonin is associated with lower plasma levels of factor VIII and fibrinogen, increasing bleeding risk ^[1];
• CYP1A2: melatonin inhibits this enzyme and may increase the bioavailability of substrate drugs (the example given by the source is fluvoxamine) ^[1];
• IMMUNOSUPPRESSANTS: risk of exacerbating myasthenia gravis ^[1];
• NIFEDIPINE: elevations in blood pressure and heart rate have been described ^[1].

THE SCOPE OF WHAT WE WRITE HERE

We give no doses or timing - that would be advice for an individual. We do draw attention to a situation typical in oncology: a patient with breast or prostate cancer, on hormonal treatment and thromboprophylaxis, meets TWO separate warnings here at once. Whether to take melatonin during cancer treatment is decided by the treating physician, who should be told about all preparations being taken, including those available without prescription. This page describes the state of knowledge and is not advice for any individual.

Sources

1. [1] Memorial Sloan Kettering Cancer Center — About Herbs: Melatonin (podsumowanie kliniczne, działania niepożądane, interakcje lekowe, przeciwwskazania w nowotworach hormonozależnych): mskcc.org ↗

WHAT THIS ENTRY IS ABOUT

Oral mucositis is the painful inflammatory reaction that develops during radiotherapy to the head and neck region and during some chemotherapy regimens, and it can make eating impossible. It is among the most common and most burdensome complications of treatment in this region; a scoping review of 151 studies on the oral consequences of irradiation lists, alongside mucositis, dental caries, periodontitis, xerostomia, candidiasis, trismus, dysphagia and osteoradionecrosis ^[4].

WHAT THE GUIDELINES SAY

• MASCC/ISOO (the Multinational Association of Supportive Care in Cancer with the International Society of Oral Oncology) reviewed 78 papers, of which 49 entered the analysis, and made a NEW SUGGESTION in favour of honey delivered topically COMBINED with systemic delivery, for the PREVENTION of oral mucositis in head and neck cancer patients receiving radiotherapy with or without chemotherapy ^[1];
• in the same paper, for the remaining interventions in the "natural and miscellaneous agents" group — herbal compounds, probiotics, saliva stimulants — no guideline was possible because the evidence was insufficient ^[1];
• separately, chewing gum was found NOT to be effective for the prevention of oral mucositis in paediatric patients with haematological or solid cancers treated with chemotherapy ^[1].

WHAT THE QUANTITATIVE REVIEWS SHOW

• a network meta-analysis of 36 randomised trials compared 13 mouthwashes in use in different countries and ranked them by SUCRA; from best downwards: aloe vera juice, Chinese herbal medicine, Bing Peng San, HONEY, Lactobacillus, chamomile, riboflavin, rehabilitation solution, benzydamine, turmeric, aluminium sulfide, povidone-iodine, chlorhexidine — honey came fourth ^[2];
• the authors of that meta-analysis state plainly that the conclusion still needs to be verified by randomised trials with larger samples ^[2];
• an umbrella review of eight systematic reviews covering 257 primary studies identified honey among the agents showing consistent improvement in quality of life across pain relief, oral function and emotional well-being ^[3].

HOW TO READ THIS HONESTLY

The strength of this recommendation is moderate and worth knowing before buying anything. A "Suggestion" on the MASCC/ISOO scale means the evidence points in a direction but is not strong enough to constitute a Recommendation. A SUCRA ranking orders interventions relative to one another and does NOT say by how much honey reduces risk — the meta-analysis abstract reports no effect size and no confidence intervals ^[2]. Note also that the guideline concerns PREVENTION, that is use from the start of treatment, not the relief of mucositis that has already developed.

WHAT IS NOT KNOWN

• no single dose or schedule has been established: the guideline speaks of topical combined with systemic delivery, without specifying the type of honey ^[1]; trials use various honeys, manuka among them, and none has been shown to be superior;
• the evidence concerns primarily head and neck cancer treated with radiotherapy; extending it to other diagnoses and other treatments is unsupported;
• in children, a review of nutritional interventions describes honey-based results as promising but without pooled data ^[5].

SAFETY POINTS TO KEEP IN MIND

• honey is high in sugars, and irradiation of the head and neck region leads to a dry mouth and radiation caries ^[4] — which is why the decision to use it, and the accompanying dental care, is taken together with the treating team and a dentist, not alone;
• honey is not a sterile product; in a patient with profound neutropenia everything taken by mouth is decided by the treating team;
• in people with diabetes, regular honey intake affects glycaemic control and needs to be discussed with the treating physician.

WHAT THIS ENTRY DOES NOT SAY

It is not a recommendation for any individual, it gives no dose or route, and it replaces neither dental prophylaxis nor pain management. It describes only where the evidence stands: there is a positive guideline suggestion of moderate strength, concerning prevention, in one specific diagnosis and one specific treatment modality.

Sources

1. [1] Yarom N i wsp. — Systematic review of natural and miscellaneous agents for the management of oral mucositis in cancer patients and clinical practice guidelines, part 2: honey, herbal compounds, saliva stimulants, probiotics and miscellaneous agents, Support Care Cancer 2020 (78 prac zidentyfikowanych, 49 wlaczonych; nowa Sugestia za miodem w profilaktyce OM w raku glowy i szyi; PMID 32056010): europepmc.org ↗
2. [2] The effect of different mouthwashes to prevent oral mucositis in patients with radiotherapy and chemotherapy: a network meta-analysis, BMC Complement Med Ther 2025 (36 badan randomizowanych, 13 plukanek, ranking SUCRA — miod na 4. miejscu; PMID 40611101): europepmc.org ↗
3. [3] Therapeutic Interventions to Manage Oral Mucositis and Their Impact on Quality of Life in Cancer Patients: An Umbrella Review, Pain Res Manag 2026 (8 przegladow systematycznych, 257 badan pierwotnych; PMID 41647299): europepmc.org ↗
4. [4] Radiation-induced oral side effects in head and neck cancer: a scoping review and interdisciplinary recommendations, BMC Oral Health 2026 (151 badan; prochnica, suchosc, martwica popromienna kosci; PMID 41862928): europepmc.org ↗
5. [5] Nutritional and Supplemental Interventions for Prevention and Treatment of Oral Mucositis in Pediatric Oncology, Nutrients 2025 (PMID 41305573): europepmc.org ↗

WHY IT MATTERS

Hormonal therapy lowers the sex hormones that protect bone. In men on androgen deprivation therapy (ADT), bone mineral density falls by an average of 5–8% during the first year and fracture risk doubles; with long-term ADT, fracture incidence is 20–30% higher than in men not on hormonal therapy ^[1]. In postmenopausal women, aromatase inhibitors and GnRH analogues increase bone turnover and reduce bone density ^[1][2].

WHAT GUIDELINES RECOMMEND

The SEOM–SEIOMM consensus (2026) states a calcium intake of 1000–1200 mg/day and vitamin D supplementation of 800–1000 IU/day for patients at risk of osteoporosis, with higher doses if dietary intake is insufficient ^[1]. The 2025 joint position statement of the bone societies (IOF, ECTS, ESCEO and others) specifies vitamin D3 800–2000 IU/day for women on an aromatase inhibitor, plus 1000 mg calcium daily if dietary calcium is low ^[2].

WHAT SUPPLEMENTATION DOES NOT COVER

Calcium and vitamin D are one component of care, not the whole of it. Once bone density falls below guideline thresholds (T-score below −2.0 on an aromatase inhibitor; more generally T-score ≤ −2.5 or a prior fragility fracture), or when additional risk factors coexist, guidelines call for antiresorptive treatment with bisphosphonates or denosumab ^[1][2]. Decisions about bone density assessment and treatment belong to the treating physician.

INTERACTIONS WITH CANCER TREATMENT

• With bisphosphonates and denosumab, adequate calcium and vitamin D are mandatory rather than optional: these drugs lower blood calcium and can cause hypocalcaemia if intake is inadequate. Registration trials of these agents typically included at least 500 mg calcium and 400 IU vitamin D per day ^[1].
• Before starting antiresorptive treatment, guidelines recommend measuring calcium, vitamin D and renal function ^[1].
• Doses higher than those above have no documented advantage in this setting; high-dose supplementation "just in case" is not the same as correcting a deficiency.

STRENGTH OF EVIDENCE

Moderate. Recommendations on calcium and vitamin D here rest on consistent society position statements and on the known mechanism of bone loss, not on randomised trials showing that supplementation alone reduces fractures in patients on hormonal therapy. The stronger evidence concerns antiresorptive drugs. The honest conclusion: calcium and vitamin D are the foundation on which the rest of management is built, but on their own they do not protect bone against the effects of hormonal therapy.

Sources

1. Beato-Zambrano C i wsp. Bone health in patients with cancer: a SEOM-SEIOMM consensus review. Clin Transl Oncol. 2026;28(8):3059-3074 (PMID 41703396): europepmc.org ↗
2. Management of aromatase inhibitor-associated bone loss (AIBL) in women with hormone-sensitive breast cancer — updated joint position statement of the IOF, CABS, ECTS, IEG, ESCEO, IMS and SIOG. J Bone Oncol. 2025;53:100694 (PMID 40726588): europepmc.org ↗
3. Coleman R i wsp. Bone health in cancer: ESMO Clinical Practice Guidelines. Ann Oncol. 2020 (PMID 32801018): esmo.org ↗

WHY PATIENTS REACH FOR IT

Ginkgo biloba is marketed to improve circulation, enhance memory and treat tinnitus ^[1]. In oncology it is taken mainly by people left with problems of concentration, memory and mental speed after chemotherapy — a real and burdensome complaint for which no treatment of proven efficacy exists. That gap is what drives sales of the supplement.

WHAT THE TRIALS SHOWED

Memorial Sloan Kettering Cancer Center summarises the evidence without ambiguity: ginkgo was INEFFECTIVE in preventing chemotherapy-associated cognitive dysfunction in breast cancer patients ^[1]. Large randomised trials, notably the Ginkgo Evaluation of Memory (GEM) study, generally show that supplementation does not improve cognitive performance or prevent Alzheimer's disease or dementia ^[1]. Cancer incidence data from GEM do not support using ginkgo to reduce cancer risk ^[1].

ADVERSE EFFECTS — WHERE THE MAIN RISK LIES. Spontaneous bleeding has been documented, including haematomas and brain haemorrhages ^[1]. Also reported: low blood sodium, seizures in susceptible individuals, and acute haemolytic anaemia in people with glucose-6-phosphate dehydrogenase (G6PD) deficiency ^[1]. In oncology this list carries more weight than in the general population: chemotherapy-induced thrombocytopenia, surgery and biopsies are settings in which a prolonged bleeding time stops being theoretical.

INTERACTIONS WITH CANCER TREATMENT

• Anticoagulants and antiplatelet drugs: ginkgo may induce or prolong bleeding time, creating a serious haemorrhage risk when combined with warfarin or similar agents ^[1].
• CYP450 enzymes: ginkgo both inhibits and induces multiple pathways (CYP3A4, CYP2D6, CYP2B6), potentially altering drug metabolism ^[1]. A large share of anticancer drugs, including kinase inhibitors, is metabolised through CYP3A4, and shifting their concentration in either direction is undesirable.
• Drugs that lower the seizure threshold: combined use increases seizure risk ^[1].
• Reduced effectiveness of efavirenz, midazolam and insulin has also been reported ^[1].

CONTRAINDICATIONS. Avoid during pregnancy, especially near childbirth, because of antiplatelet properties that prolong bleeding time ^[1].

STRENGTH OF EVIDENCE

Moderate — and pointing towards absence of benefit. This grade reflects the fact that the conclusions of ineffectiveness come from randomised trials, including the large GEM study, rather than from observation ^[1]. The harm evidence is of a different kind: it rests on case reports and interaction data, so it does not allow the frequency of complications to be estimated — but it does establish that they are possible and serious.

WHAT THIS ENTRY DOES NOT SAY

It neither recommends nor advises against anything for any individual, and gives no doses. It states what the trials showed and which interactions are documented. The decision to take or stop any supplement before surgery, during chemotherapy or while on anticoagulation belongs to the treating physician, who knows the full list of medicines taken.

SOURCES.

• ^[1] Memorial Sloan Kettering Cancer Center, About Herbs: Ginkgo

Sources

1. [1] Memorial Sloan Kettering Cancer Center — About Herbs: Ginkgo: mskcc.org ↗

WHERE THE IDEA CAME FROM

Pomegranate (Punica granatum) is a rich source of polyphenols, and laboratory work showed effects on prostate cancer cell proliferation and apoptosis. In 2006 the first clinical trial in men with rising PSA after prostatectomy or radiotherapy was published: a phase II study with no control group, in which mean PSA doubling time increased from 15 months to 54 months ^[1]. The authors stated explicitly that the result warranted testing in a placebo-controlled study ^[1] — yet it is precisely the "15 to 54 months" figure that still circulates today.

WHAT THE CONTROLLED TRIAL SHOWED

A multi-institutional, double-blind, placebo-controlled study enrolled 183 men with rising PSA after primary therapy, randomly assigned 2:1 (extract 102, placebo 64, juice 17) ^[2]. The primary endpoint was change in PSA doubling time. The authors' conclusion is unambiguous: compared with placebo, pomegranate extract did NOT significantly prolong PSA doubling time ^[2].

WHY THE EARLIER RESULT WAS MISLEADING

In the placebo-controlled study, PSA doubling time lengthened significantly in BOTH arms — in the placebo group the median rose from 11.1 months at baseline to 15.6 months ^[2]. This shows that a lengthening of PSA doubling time during follow-up does not by itself demonstrate that a preparation works. The 2006 phase II study had no control group and so could not tell the two apart. It is a textbook illustration of why an uncontrolled result is not enough.

A GENETIC SUBGROUP — WHAT MUST NOT BE READ INTO IT: In an exploratory analysis, men with the manganese superoxide dismutase (MnSOD) AA genotype taking the extract had a change in median PSA doubling time from 13.6 to 25.6 months ^[2]. The authors themselves note that this observation requires prospective hypothesis testing and validation ^[2]. A subgroup identified after the fact is not a basis for using the preparation.

INTERACTIONS WITH CANCER TREATMENT

• CYP3A: in rat studies pomegranate juice inhibited CYP3A activity similarly to grapefruit juice, but human clinical trials did NOT show clinically relevant inhibition ^[3]. Equating pomegranate with grapefruit is therefore unwarranted.
• CYP2C9: inhibition was shown in rats (increased tolbutamide bioavailability); in humans no effect on CYP2C9 activity was found ^[3].
• warfarin: a case report suggests that pomegranate juice may interact with warfarin ^[3].
• metformin: in a rat model, prior administration of the juice reduced metformin efficacy; clinical relevance remains undetermined ^[3].

TOLERABILITY: Pomegranate is generally well tolerated; daily consumption of about 240 ml of juice for over two years produced no significant adverse effects ^[3]. Mild effects reported included nausea, constipation and decreased appetite, with diarrhoea at higher doses in some patients ^[3].

WHAT FOLLOWS

Pomegranate as a fruit and juice is a dietary component with a good safety profile. There is, however, no controlled-trial evidence that pomegranate extract slows the rise of PSA after treatment for prostate cancer. Decisions about management of a rising PSA are made by the treating physician; a supplement replaces neither surveillance nor treatment.

Sources

1. [1] Pantuck AJ i wsp., Phase II study of pomegranate juice for men with rising PSA following surgery or radiation for prostate cancer, Clin Cancer Res 2006: pubmed.ncbi.nlm.nih.gov ↗
2. [2] Pantuck AJ i wsp., A randomized, double-blind, placebo-controlled study of the effects of pomegranate extract on rising PSA levels in men following primary therapy for prostate cancer, Prostate Cancer Prostatic Dis 2015;18(3):242-8: pubmed.ncbi.nlm.nih.gov ↗
3. [3] Memorial Sloan Kettering Cancer Center, About Herbs: Pomegranate (interakcje i tolerancja): mskcc.org ↗

WHAT THE EVIDENCE SAYS The strongest available appraisal is a 2022 meta-analysis (Nutrition Research) of 12 controlled trials and 1,184 patients with cancer cachexia ^[1]. The result is split: quality of life improved (standardised mean difference 0.70; 95% CI 0.01–1.40; p=0.048) and survival was longer (median survival ratio 1.10; 95% CI 1.02–1.19; p=0.014), while body weight did not increase (SMD 0.10; 95% CI −0.06 to 0.26; p=0.236) and lean body mass did not change significantly (SMD −0.17; 95% CI −0.36 to 0.03; p=0.095) ^[1]. The authors' conclusion is literal: n-3 PUFAs improved quality of life and survival, but not body weight ^[1].

STRENGTH OF EVIDENCE — MODERATE, RESULTS DIVERGENT The upper confidence bound for quality of life (1.40) and the lower bound for survival (1.02) show these are borderline findings drawn from trials of varying methodology ^[1]. Cancer cachexia cannot be reversed by nutritional measures alone — we write about this separately in the entry on nutrition in cachexia — and omega-3 does not change that picture.

INTERACTIONS AND SAFETY The most common concern is bleeding. A meta-analysis of 11 randomised trials covering 120,643 participants (Journal of the American Heart Association, 2024) found no increase in bleeding events with omega-3 supplementation (rate ratio 1.09; 95% CI 0.91–1.31; p=0.34); haemorrhagic stroke, intracranial bleeding and gastrointestinal bleeding were likewise similar ^[2]. The caveat concerns high-dose purified EPA: in a prespecified analysis the relative risk of bleeding rose by 50%, with only a very modest rise in absolute risk (0.6%) ^[2]. Risk tracked the dose of EPA (risk difference 0.24; 95% CI 0.05–0.43; p=0.02), not the background use of antiplatelet therapy (risk difference −0.01; 95% CI −0.02 to 0; p=0.056) ^[2]. AN IMPORTANT CAVEAT: the abstract of this meta-analysis does not separate out cancer patients, so carrying its result over to people on chemotherapy or before surgery is extrapolation rather than direct data ^[2].

A separate, unsettled question is the use of antioxidant preparations during chemotherapy and radiotherapy — the literature calls the risk–benefit balance in that situation a controversial topic. The National Cancer Institute states the general rule: “Tell your doctor if you're taking any dietary supplements, even vitamins, no matter how safe you think they are” ^[3].

THE SCOPE OF WHAT WE WRITE HERE We give no target doses or dosing schedule, because that would be advice for an individual rather than a description of the state of knowledge. Nor did we find data on patients taking warfarin or direct oral anticoagulants concurrently — the meta-analysis cited examined only antiplatelet background therapy ^[2]. This page is not advice for any individual.

Sources

1. Jin X et al. — Omega-3 polyunsaturated fatty acids improve quality of life and survival, but not body weight in cancer cachexia: a systematic review and meta-analysis of controlled trials, Nutrition Research 2022: europepmc.org ↗
2. Javaid M et al. — Bleeding Risk in Patients Receiving Omega-3 Polyunsaturated Fatty Acids: A Systematic Review and Meta-Analysis of Randomized Clinical Trials, Journal of the American Heart Association 2024: europepmc.org ↗
3. National Cancer Institute — Complementary and Alternative Medicine (CAM): cancer.gov ↗

WHAT THIS ENTRY COVERS

This concerns cancer-related fatigue — exhaustion out of proportion to exertion and not relieved by rest, the most commonly reported symptom during cancer treatment. The entry covers one specific botanical: the root of American ginseng (Panax quinquefolius). It does NOT cover Asian ginseng (Panax ginseng) or Korean red ginseng — different species with a different ginsenoside profile, and the recommendation cited below was formulated for the American species only.

WHAT THE EVIDENCE SHOWS

The principal evidence is a multicentre, double-blind, placebo-controlled randomised trial, NCCTG N07C2 (JNCI, 2013; PMID 23853057): 364 patients from 40 institutions, 2,000 mg of ground root daily for 8 weeks.

• primary endpoint (general subscale of the MFSI-SF) at 8 weeks: change score 20.0 (SD 27) with ginseng versus 10.3 (SD 26.1) with placebo, p = .003
• the difference was NOT significant at 4 weeks — the effect emerged only with longer use

The ASCO/Society for Integrative Oncology guideline on the management of cancer-related fatigue lists American ginseng among options that "may be recommended in adults undergoing cancer treatment", while stating that certainty and quality of evidence for fatigue interventions are low to moderate. This is conditional wording ("may be"), not a strong recommendation.

A smaller, more recent placebo-controlled randomised trial in Supportive Care in Cancer (2026; PMID 41838185) in 65 survivors of gastrointestinal cancer reported improved fatigue scores at 4 weeks (3.99 ± 0.86 vs 5.37 ± 1.27; p < .001), but it used a Panax ginseng extract at 250 mg — a different species and dose from N07C2, so the two results should not be read as confirming one another.

WHAT THESE RESULTS DO NOT SAY

They do not say that ginseng affects the course of the cancer — the endpoint measured was how patients feel, not survival or treatment response. Nor do they make it a first-line measure: in the same guideline the best-documented interventions for fatigue are physical activity and psychological approaches, not oral products. Finally, it is unknown whether the effect persists after stopping, or whether it applies to fatigue that continues long after treatment ends.

INTERACTIONS WITH CANCER TREATMENT — MANDATORY SECTION.

• WARFARIN and other vitamin K antagonists: ginseng has been described as potentially lowering INR, i.e. weakening anticoagulation. In cancer patients, in whom thrombosis is a frequent complication, this matters practically.
• DRUGS METABOLISED BY CYP3A4, including tyrosine kinase inhibitors (e.g. imatinib): liver injury has been reported with concurrent ginseng use. The interaction mechanism is the same as for St John's wort, though its direction and magnitude are less well documented.
• ANTIDIABETIC DRUGS: ginseng may lower blood glucose, so the effect adds to glucose-lowering therapy.
• OESTROGEN-LIKE ACTIVITY: ginsenosides show oestrogenic activity in vitro, and ethanol-extracted preparations contain more of them. N07C2 deliberately used pure ground root rather than an ethanol extract. In hormone-dependent cancers this is a reason for caution, although clinical evidence of harm is lacking.

THE DECISION BELONGS TO THE PHYSICIAN

Cancer-related fatigue has reversible causes that must be excluded first — anaemia, hypothyroidism, pain, sleep disturbance, depression, drug effects. A supplement does not replace that work-up. Introducing any botanical product during chemotherapy, targeted therapy or anticoagulation requires agreement with the treating physician and clinical pharmacist.