A patient-focused look at why vitamins, herbs, and special diets are used during and after cancer treatment, what oncology teams know, and why some products remain outside the conversation.
Total responses: 309
Complete responses: 125
Countries: 6
Survey ID: 8893408
Quick Read — Key Findings
Explore the complete patient story, exact response patterns, practical implications, and open-response themes.
People living with cancer may add vitamins, herbs, teas, probiotics, or special diets to manage symptoms, rebuild energy, or feel more in control. These choices are often made between appointments, after advice from family, support groups, practitioners, or online searches.
The National Cancer Institute explains that natural does not automatically mean safe and that some complementary products can interact with cancer medicines. The National Center for Complementary and Integrative Health also advises people with cancer to speak with their healthcare team before adding products or practices. The challenge is not simply whether patients use them. It is whether the conversation feels routine, informed, and safe enough to be honest.
We asked people with cancer across the United States, the United Kingdom, Canada, Italy, France, and Germany about what they use, why they use it, where they get information, and how much their oncology team knows.
Most respondents had used at least one complementary substance or dietary protocol after diagnosis.
What the pattern shows: Vitamins and minerals are the largest single category at 47.2%. Yet another 38.5% selected herbs, medicinal mushrooms, special diets, or digestive products. Complementary use is therefore broader than a standard multivitamin and may involve several products that patients do not naturally think of as medicine.
What may be behind it: Vitamins, teas, powders, and wellness products are easy to buy and are often linked with energy, immunity, digestion, or recovery. Because they are familiar and available without a prescription, patients may see them as everyday self-care rather than something that needs a treatment-safety review.
Why this matters: A useful conversation needs the exact product, dose, timing, and reason for use. Asking only about “medicines” or “vitamins” may miss herbs, concentrated extracts, powders, and restrictive diets.
Patients described several different reasons for adding products alongside cancer care.
What the pattern shows: Vitality and energy lead at 38.5%, followed by symptom relief at 23.9%. Together, these findings suggest that most patients are trying to cope with how cancer and treatment affect daily life. At the same time, 19.3% hope the product will help fight, shrink, or cure cancer alongside medical treatment.
What may be behind it: Fatigue, changes in appetite, treatment side effects, anxiety, and the wish to regain some personal control can make additional products feel practical or hopeful. The same product can therefore mean very different things to different patients.
Why this matters: Care teams need to ask not only what a patient is taking, but what they expect it to do. A person seeking relief from nausea needs a different discussion from someone expecting an anticancer effect.
Cancer treatment changes over time, and supplement use can change with it.
What the pattern shows: 60.7% remember being asked about supplements during the first consultation or at later check-ins. However, 39.3% were never explicitly asked or could not remember being asked. The gap is therefore not only whether the topic is raised, but whether it is repeated clearly enough to stay visible throughout care.
What may be behind it: Supplement use can change after side effects appear, after active treatment ends, or after patients receive advice from friends or online sources. Patients may also add a tea, powder, or vitamin without viewing it as a change in medication.
Why this matters: A neutral question before a new treatment cycle, surgery, or medication change may identify products that were not present at the first visit and reduce avoidable interaction risks.
Patients may mention a multivitamin while leaving out herbs, teas, powders, or special diets.
What the pattern shows: 61.4% report full disclosure, but 24.4% share only part of what they use and 14.2% share nothing. The larger hidden area is partial disclosure, not complete silence.
What may be behind it: Patients may mention a familiar multivitamin but leave out occasional teas, powders, skin products, or special diets because these feel less medical. They may also assume that products used only sometimes are not important enough to report.
Why this matters: A partly complete list can still omit the product most likely to interact with treatment. Specific prompts and a written product list are more reliable than a general question about supplements.
Patients often search for answers between appointments and compare advice from several sources.
What the pattern shows: Independent online research is the largest single source at 27.8%, while only 17.5% select their treating oncologist or oncology nurse as the main source. Around four in five respondents chose a main source outside their treating oncology team.
What may be behind it: Questions often arise between appointments, when search engines, peer stories, and wellness content are immediately available. These sources may also provide simple answers, personal experiences, or a sense of hope that is harder to find in a short clinical visit.
Why this matters: Outside information-seeking will continue. The safer response is to give patients trusted resources and make it easy to bring claims, labels, and questions back for a calm review.
The reasons for withholding are practical and emotional, not simply patient resistance.
What the pattern shows: No single reason explains non-disclosure. Assuming natural products are safe, fear of judgment, limited consultation time, fear of being told to stop, doubts about provider knowledge, and simply not being asked all contribute.
What may be behind it: Some patients may not realise that a natural product can affect treatment. Others may worry that raising the topic will lead to criticism or remove a choice that helps them feel more in control. When appointments feel rushed, the easiest option may be to say nothing.
Why this matters: Nonjudgmental language and a clear process for reviewing products can turn hidden use into shared decision-making. The goal is not to dismiss patient choices, but to understand them well enough to protect safety.
Keep one complete list of everything you take or use, including teas, powders, gummies, creams, and special diets. Bring the package or a label photo so the oncology team can check ingredients and doses.
Ask in a neutral way at the first visit and again before treatment changes. A question such as “What vitamins, herbs, teas, or special diets are you using right now?” is more specific than asking only about medicines
Explain what is known, what is uncertain, and what needs to be paused or monitored. When the answer is unclear, involve an oncology pharmacist, dietitian, or integrative oncology professional rather than ending the conversation.
//People Also Ask
Direct answers to the questions healthcare professionals are most likely to ask about these findings.
