About alternative therapies

Alternative therapies are treatments that are used instead of conventional medical treatment. They are often confused with complementary therapies. Complementary therapies are treatments that are taken with conventional treatment.

Many alternative therapies claim to actively treat or even cure cancer. But there’s no scientific proof to show this. No alternative therapies have ever been proven to cure cancer or slow its growth.

Some people seek alternative therapies because having unpleasant side effects from conventional therapies may be frightening. However many people with early cancer can be cured with conventional medical treatments.

Doctors usually advise against using alternative therapies because alternative therapies have not been tested in the same way as conventional treatments. Although some alternative therapies may do no harm, others can be very harmful and may affect how well conventional treatment works.

Always speak to your doctor before making a decision about alternative therapies. You can also call our cancer support specialists.

Alternative therapies and cancer

Alternative therapies are different from complementary therapies. Alternative therapies are used instead of conventional treatments. They may claim to actively treat or even cure cancer. But there’s no scientific proof to back up these claims.

No alternative therapies have ever been proven to cure cancer or slow its growth.

There have been cases where false claims about alternative therapies have led some people to refuse 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. This means that when you read about them or are told about them, they sound very effective. Therapists may use scientific language to make their claims sound more convincing. But, many are based on unproven or disproven theories of how cancer begins or stays in the body.

Claims may be based on the therapy’s results when it is tested on cancer cells in a laboratory. But this can differ greatly from how the therapy will affect a person with cancer. Claims that an alternative therapy has an anti-cancer action in the laboratory do not mean it will have any effect on someone with cancer.

Very few suppliers of alternative medicines have carried out scientifically controlled clinical trials for their products. Many alternative therapies rely on individual’s stories or testimonials as evidence that they work. This is called anecdotal evidence and is the least reliable type of evidence. This is 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.

'I’m a little bit skeptical about a lot of alternative therapies.'


Why do some people consider alternative therapies?

There are various reasons why some people may choose to try an alternative therapy. Sometimes, it’s because they feel that conventional medical 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 medical treatments.

If you’ve been told by your doctors that the cancer can’t be cured, you may find it very hard to accept. Some people in this situation may look into alternative therapies. 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.

Even when a cancer is advanced, conventional treatments can help to control it and prolong people’s lives, often for many years.

Second opinion

If your doctor tells you that further treatment won’t help to control the cancer, you may understandably find it very hard to accept. In this situation, some people find it helps to have a second medical opinion.

The second doctor may be able to offer you another type of conventional treatment. Or, they may confirm what you’ve already been told. This may help you to accept that everything that may help has been tried. If you still want to have treatment, you could ask if there are any cancer research trials that might be appropriate for you.

We have more information about coping with advanced cancer and understanding cancer research trials (clinical trials).

Get advice and support before starting an alternative therapy

If you’re considering using 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 they usually advise against using alternative therapies.

If you decide to use an alternative therapy, it’s important to check it’s safe. Always check the credentials of the therapist.

Alternative therapies can be expensive and some can cause serious side effects. They can also make you feel unwell and be harmful to your health.

Types of alternative therapy

There are many types of alternative therapy. We have covered alternative therapies most well-known by people with cancer, but haven’t included them all. If you want to find out more about an alternative therapy not mentioned here, you may find information about it from these organisations. You can also call the Macmillan Support Line on 0808 808 00 00 if you want to talk through any aspect of alternative therapy.

Amygdalin (Laetrile®, Vitamin B17)

Amygdalin is a compound found in bitter almonds, and in peach and apricot stones. When amygdalin is processed by the body, it can be changed to cyanide, a type of poison.

A man-made form of it is called Laetrile. It is also sometimes called vitamin B17, although it isn’t actually a vitamin.

Laetrile has been sold 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 poison cancer cells without damaging normal cells and tissues. But there’s no medical evidence to support this. 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 doctor.

Essiac® (Vitaltea®, Flor-essence®)

Essiac contains burdock root, sheep sorrel, slippery elm and rhubarb. It is taken as a drink. It’s usually sold as a nutritional supplement. Some websites claim Essiac can slow down the growth of cancer, or even cure it. But there’s no medical evidence that taking Essiac helps treat cancer or improve your quality of life.

Essiac interferes with an enzyme in the body that regulates hormones and vitamin D. It also has an effect on how the body deals 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 cancer doctor.

Metabolic therapy

Metabolic therapists think of cancer as the result of an 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. Metabolic treatments vary from one practitioner to another, and may include:

  • a diet of raw fruit and vegetables that has no processed
  • foods or salt
  • vitamins and minerals
  • enzymes or chemicals
  • coffee enemas.

These are said to flush toxins out of the body, allowing it to heal. But there’s no medical evidence to support claims they help treat cancer.

A recent study compared the results of using a metabolic therapy with chemotherapy. The metabolic therapy included 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

This 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. Nutritional supplements are also given, and coffee enemas are used to flush out toxins.

Some alternative therapists claim the Gerson diet is effective in treating cancer, but there is no medical evidence to support this.

If you have any questions about alternative diets or are thinking of following one, get advice from your doctor, specialist nurse or dietitian.

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. Risks of using coffee enemas include infections and they can cause serious damage to the large bowel.

Diets that claim to treat cancer

There are a number of diets, in addition to the Gerson diet, 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 are used. Other diets are based on claims that some foods ‘feed’ cancer or affect the pH (acidity) of the body.

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.

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.

There’s no medical evidence that these diets can cure cancer or help people with advanced cancer live longer.

It’s understandable that some people are attracted to diets that seem to offer hope.

Some people get pleasure and satisfaction from preparing special diets. But, following diets isn’t right for everyone. Some people find them boring, expensive, time-consuming, or even unpleasant to eat. Some might feel guilty if they don’t follow the diet properly. People can also feel angry and let down if the diet doesn’t help their cancer in the way they had hoped.

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.

Megavitamin therapy

This type of alternative therapy involves taking very large doses of vitamins as a way of preventing and treating cancer. However, there’s no evidence that taking large doses of vitamins is helpful in treating cancer. Some vitamins can be harmful in high doses.

High-dose vitamin C is one of the most common types of megavitamin therapy. Scientific studies have found no benefit for people with cancer taking high-dose vitamin C by mouth (orally). More recently, studies are looking at whether high-dose vitamin C would work better if given into the bloodstream (intravenously). A number of clinical trials (mainly in the USA) are researching this. Some studies are also testing the effects of high-dose intravenous vitamin C when given alongside conventional cancer treatments. But so far, there’s no reliable evidence that intravenous high-dose vitamin C helps 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 doctor 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 Laetrile at the same time as high-dose vitamin C.

High-dose vitamin C is not suitable for people who have kidney problems, a condition that causes iron overload (haemachromatosis) or who have G6PDH deficiency.

Talk to your doctor if you have any of these problems and are thinking of taking high-dose vitamin C.

Our information

Back to Access to treatment

Finding out your treatment options

Knowing basic information about your type of cancer and different treatments options can help you to make an informed treatment decision.

Making your decision

If  you’re struggling to come to a decision about treatment, try following these five steps.