Browser does not support script.
Skip to main content
Find out how we produce our information|
Alternative therapies are treatments that are used in place of conventional treatments. They may claim to treat or even cure cancer. There’s no scientific proof to back this up, and no alternative therapies have been proven to cure cancer or slow its growth.
There have been cases in which false claims made about alternative therapies have led some patients to turn away from conventional treatments that could have helped them.
No reputable alternative therapist will claim to be able to cure cancer.
Alternative therapies are sometimes very cleverly marketed so that when you read about them or are told about them, they sound very effective. Therapists may use scientific language to make their claims more convincing. But, many are based on unproven or disproven theories of how cancer begins or is sustained in the body.
Claims may be based on the therapy’s results when tested on cancer cells in a laboratory setting. But a therapy’s activity against cancer cells in a laboratory can differ greatly from how the therapy will affect someone with cancer. So claims that an alternative therapy has an anti-cancer action in the laboratory don’t necessarily mean it will be effective if taken by someone with cancer.
Very few suppliers of alternative medicines have carried out scientifically controlled clinical trials| for their products. Many alternative therapies rely on individuals' stories or testimonials as evidence that they work. This is called anecdotal evidence. It is the least reliable type of evidence because it’s usually not possible to check whether the effect described is due to the treatment or something else. It’s also not possible to check that the person’s story is true or that the person even existed or had cancer.
There are various reasons people may look to alternative therapies. Sometimes, it’s because they feel that conventional treatment can’t help them or could be harmful. The idea of having cancer treatments, which may cause unpleasant side effects, can be frightening for some people. However, many people with early cancer can be cured by conventional treatments.
If you’ve been told by your doctors that the cancer can’t be cured, this can be very hard to accept and you may look to an alternative therapy. However, if a cancer can’t be cured by conventional medical treatment, it’s equally true that it won’t be cured with alternative treatment. In this situation, some alternative therapies may do no harm, but some could be very harmful.
If you’re finding it hard to accept that further treatment won’t help to control the cancer, it can sometimes help to have a second opinion|. The second cancer specialist may see things differently and offer you another type of conventional treatment. Alternatively, if they confirm what you’ve already been told, this may help you to accept that everything that may help has been tried. If you feel very strongly that you want to continue having treatment to try to combat the cancer, you could also ask if there are any cancer research trials| that might be appropriate for you.
If you've been told that your cancer can't be cured, you might find it helpful to see our section about coping with advanced cancer|.
If you’re considering using complementary or alternative therapies, talk to your doctor for advice and support. Doctors are generally supportive of people using any complementary therapies that may help them cope better with their illness, but may advise against using alternative therapies.
Only you can decide whether or not to use alternative cancer therapies. If you do decide to use an alternative therapy, it’s important to check it’s safe and to check the credentials of the therapist offering the treatment. Alternative therapies can be expensive and some can cause serious side effects, make people feel unwell and be harmful to health.
There are many types of alternative therapy and we can’t cover them all in this section. If you want to find out more about an alternative therapy not mentioned here, you may be able to get more information by calling the Macmillan Support Line|, who will be able to talk through any aspect of alternative therapy.
Amygdalin is a compound found in bitter almonds, and in peach and apricot stones. A synthetic form of it is marketed as Laetrile®. It is also sometimes called vitamin B17, although it isn’t actually a vitamin.
Laetrile has been marketed since the 1970s. Many websites that sell it claim it can slow or stop the growth of cancer. They sometimes also claim that Laetrile is able to selectively poison cancer cells without damaging normal cells and tissues. But there’s no evidence to support the theory this is based on. A review of studies looking at the outcomes for people with cancer taking Laetrile found no evidence that it can control or cure cancer.
Laetrile can have serious side effects. Some people have had cyanide poisoning while taking it, and a few people have died as a result. The sale of Laetrile has been banned by the European Commission and by the Food and Drugs Administration (FDA) in the USA. Unlike conventional medicines, the manufacture of Laetrile isn’t controlled. So if you buy Laetrile there isn’t any way of knowing what it contains or if it’s contaminated with other substances.
If you’re thinking of taking Laetrile, it is best to discuss this with your cancer specialist.
Essiac contains burdock root, sheep sorrel, slippery elm and rhubarb and is taken as a drink. It was developed and named by Rene Caisse, a Canadian nurse, (Essiac is Caisse spelled backwards). Essiac is usually sold as a nutritional supplement.
Some websites claim that Essiac can slow down the growth of cancer, or even cure it. However, there’s no scientific evidence that taking Essiac can help to treat cancer or improve quality of life.
Essiac interferes with an enzyme (cytochrome p450) in the body that’s responsible for regulating hormones, vitamin D and dealing with toxins. This may mean taking Essiac with other treatments could make them less effective or increase side effects.
It’s important not to take Essiac during cancer treatment or with any other medicines without first checking with your doctor.
Metabolic therapists think of cancer as the result of a metabolic imbalance caused by a build-up of ‘toxic substances’ in the body. They claim they can treat the cause of the disease by removing ‘toxins’ and strengthening the immune system so the body can heal itself.
Metabolic treatments vary from one practitioner to another, and may include a ‘natural food’ diet, coffee enemas, vitamins, minerals, enzymes or chemicals. These are said to flush toxins out of the body, allowing it to heal. But, there’s no evidence to support claims that these help in the treatment of cancer.
A recent study compared the results of using a metabolic therapy (Gonzalez therapy) designed for patients with advanced pancreatic cancer with conventional cancer treatment (chemotherapy with gemcitabine). The metabolic therapy included pancreatic enzymes, nutritional supplements, detoxification and organic foods. The study found that the patients who had the chemotherapy survived three times longer and had better quality of life than those who chose metabolic therapy.
Gerson therapy is one of the most well-known metabolic therapies. The diet is based on organic fruit and vegetables, taken mainly as a juice prepared with a juice extractor. In addition, a number of nutritional supplements are given, and coffee enemas are used to ‘flush out toxins’.
This diet needs a lot of time and commitment and may be expensive to follow. Some alternative therapists claim that the Gerson diet is effective in treating cancer, but evidence from research studies does not support this claim.
Possible side effects of Gerson therapy include nausea, vomiting, stomach cramps, a high temperature and headaches. The high levels of hormones and extracts used can sometimes make people feel unwell and may disrupt the body’s metabolism. Other possible side effects of the therapy relate to the use of enemas and include perforation or rupture of the large bowel (colon), infections, and fluid and electrolyte imbalances.
If you have any queries about alternative diets or are thinking of following one, get further advice from your doctor, specialist nurse or dietitian.
There are a number of diets, in addition to the Gerson and Gonzalez diets, that claim to treat cancer. Some claim to rid the body of toxins. Many of these diets are vegetarian or vegan. They involve eating food that is raw, sugar-free and low in salt. Sometimes vegetable or fruit juices and high doses of vitamins, minerals or enzymes may be used. Other diets are based on claims that certain foods ‘feed’ cancer or affect the pH (acidity) of the body.
Advocates of these diets may make dramatic claims that they can cure people with advanced cancer. It’s completely understandable that people with cancer should be attracted to diets that seem to offer the hope of a cure. However, there’s no scientific evidence that these diets can cure cancer or help people with advanced cancer live for longer.
Some people get pleasure and satisfaction from preparing special diets. It can be rewarding to feel that you’re doing something positive for your health and to have something that you are in control of. But, following diets is not right for everyone. Some people find them boring, too expensive, time-consuming to prepare or even unpleasant to eat. There’s also a danger that people can feel guilty if they don’t follow the diet ‘properly’. People can also feel very angry and let down if they are led to believe that a particular diet will cure or control their cancer and this does not happen.
Diets that are high in fibre and low in calories and protein are not appropriate for people who have problems maintaining their weight because of cancer or its treatment. Instead, people who are underweight need protein and calories from any source.
If you choose to follow a diet that cuts out particular types of food, it’s important to make sure you aren’t missing out on important nutrients in your diet. For example, if you follow a dairy-free diet, it’s important to replace the calcium that you would otherwise get from dairy products with other calcium-rich foods.
This type of alternative therapy advocates taking very large doses of vitamins (megavitamin therapy) as a way of preventing and treating cancer. However, there’s no evidence that taking large doses of vitamins is helpful in treating cancer, and in high doses some vitamins can be harmful.
High-dose vitamin C is one of the most widely used forms of megavitamin therapy. Scientific studies have found no benefit for people with cancer taking high-dose vitamin C by mouth (orally). More recently, there has been interest in whether high-dose vitamin C would work better if given directly into the bloodstream (intravenously). A number of clinical trials (mainly in the USA) are investigating this. Some studies are also testing the effects of high-dose intravenous vitamin C when it’s given alongside conventional cancer treatments. However, at present there isn’t reliable evidence that intravenous high-dose vitamin C can help to treat cancer.
High-dose vitamin C can make many cancer treatment drugs, such as cisplatin, doxorubicin, imatinib and vincristine, less effective. It may also interfere with how radiotherapy works. So it’s important to tell your cancer specialist before having high doses of vitamin C, particularly if you’re planning on using it during, or within a few weeks of, cancer treatment.
High-dose vitamin C may also interact with some complementary and alternative therapies. There have been cases of severe cyanide poisoning in people taking amygdalin (Laetrile) at the same time as high-dose vitamin C.
People who have kidney problems, a condition that causes iron overload (haemachromatosis) or who have G6PDH deficiency should always consult their doctor before taking high-dose vitamin C supplements.
Content last reviewed: 1 October 2011
Next planned review: 2013
For answers, support or just a chat, call the Macmillan Support Line free (Monday to Friday, 9am-8pm)
If you have any questions about cancer, need support or just want someone to talk to, ask Macmillan.
If you have any questions about Macmillan we would love to hear from you| .
You can also follow us| on Facebook, Twitter, Flickr or YouTube.
© Macmillan Cancer Support 2013
what are these?|