Can any foods help with my prostate cancer?

Some studies suggest that certain foods could help slow down the growth of prostate cancer or lower the chance of it coming back after treatment. We describe some of these foods below. With all of these foods, the evidence isn't very strong and other studies haven’t shown any effect. This means we can’t say for sure whether any of these foods can help.

Soya beans and other pulses

Soya beans belong to a group of plants called pulses or legumes. Some of the chemicals in soya beans are also found in other pulses, such as kidney beans, chickpeas and lentils.

We don’t know whether pulses have an effect on prostate cancer, but they are a good source of protein and other nutrients that are important for general health. Three heaped tablespoons of cooked pulses can count as one of your five daily portions of vegetables.

Soya beans are available in some supermarkets in the frozen foods or dried snacks sections. If you decide to eat more soya beans, you could try products such as soya milk and yoghurts, tofu, soya bread, miso and tempeh. Try to avoid products with added salt and sugar.

Green tea

Some studies suggest that chemicals in green tea might protect against prostate cancer growth and advanced prostate cancer. But we can't say for certain about the effects of green tea, as other studies haven't seen the same benefits.

If you decide to drink green tea, you'll need to brew it for five minutes to make sure plenty of nutrients are released, making the flavour quite strong. You might want to choose a decaffeinated variety, especially if you have urinary problems, as caffeine can irritate the bladder.

Tomatoes and lycopene

Tomatoes contain a plant chemical called lycopene. Some studies have suggested that eating tomatoes could help to protect against prostate cancer growth and aggressive prostate cancer. But experts recently looked at all of the studies on lycopene and only found limited evidence of any benefit for men with prostate cancer. So we don't know if it's helpful.

Cooked and processed tomatoes, such as tomato sauces, soups, purees and pastes, are a better source of lycopene than fresh tomatoes. This is because the body finds it easier to absorb lycopene from tomatoes that have been cooked or processed, particularly with a little oil. Try to choose low-salt and low-sugar options as some products, such as ketchup, have added salt and sugar.

Lycopene is also found in watermelons, pink grapefruits, guava and papaya. As lycopene isn’t stored inside the body for very long, you need to eat foods containing lycopene regularly to keep some in your body. You may need to avoid grapefruit if you take certain medicines, including some drugs to lower cholesterol or blood pressure, drugs to treat erection problems, and warfarin to thin your blood. Ask your doctor or pharmacist if you’re unsure.

Cruciferous vegetables

These include broccoli, cauliflower, cabbage, Brussels sprouts, bok choy, spinach and kale. Some studies suggest that cruciferous vegetables may help slow down the growth of prostate cancer and reduce the risk of advanced prostate cancer. But we need more research into the effects of cruciferous vegetables, as other studies haven’t found this.

Pomegranate

Some studies suggest that pomegranate juice may be good for men with prostate cancer. But we don't yet know if this is the case. If you want to try pomegranate juice, choose a variety with no added sugar. You may need to avoid pomegranate if you use certain prescription drugs. Ask your pharmacist for advice.

Are there any foods I should eat less of?

There is some evidence that eating a lot of certain foods may be harmful for men with prostate cancer. We describe some of these foods below. There's no need to cut any of these foods out of your diet completely. We need more research to fully understand their effect on prostate cancer, but you can still eat most of them in moderate amounts as part of a healthy, balanced diet.

Dairy foods and calcium

Dairy foods are high in calcium. Calcium is important for strong bones and your overall health, so you need some calcium in your diet – around 700mg a day, or 1200-1500mg a day if you're on hormone therapy.

Normal amounts of calcium and dairy foods won’t increase your risk of advanced prostate cancer. But some studies suggest that eating a lot of calcium might increase the risk of your prostate cancer growing and spreading. Others have found no link, but it may be an idea to avoid eating more than 2000mg of calcium – the amount in about 1.6 litres of milk – a day.

Meat

The effect of red and processed meat on men with prostate cancer isn’t clear. Some research suggests that eating too much may raise your risk of aggressive and advanced prostate cancer, while other research hasn’t found any effect. Some studies have also suggested that a diet that is low in meat but high in fruit and vegetables may help to slow the growth of prostate cancer.

Red meat includes beef, pork and lamb. Try to eat no more than 500g of cooked red meat (700 to 750g before cooking) a week. Processed meat is meat that has been preserved by smoking, curing or salting, or with preservatives. It includes ham, bacon and some sausages, such as salami. It's best to avoid processed meat.

Large amounts of meat that have been cooked at very high temperatures or are very well done, such as barbecued, grilled or fried meat, may also increase your risk of advanced cancer. This may be caused by chemicals that are made when meat burns, as they can damage cells. So try to avoid eating lots of meat cooked at very high temperatures.

Fat

You need to eat some fat for your body to work properly. But eating too much fat can make you put on weight, which raises your risk of being diagnosed with aggressive or advanced prostate cancer.

There are different types of fat. Replacing animal fats with vegetable oils may help men with prostate cancer to live for longer. There is also some research that suggests eating lots of saturated fat might be linked with an increased risk of prostate cancer coming back after surgery, and of developing advanced prostate cancer. But we need more research to know for sure whether this is the case, as other studies haven't found a link.

Should I use supplements or herbal remedies?

Some people like to use dietary supplements or herbal remedies, but there’s little evidence that they’re helpful for men with prostate cancer. Some may even be harmful.

Dietary supplements

There’s little evidence that supplements are helpful for men with prostate cancer. Some supplements may also interfere with your treatment for prostate cancer, so let your doctor, nurse or dietitian know if you’re taking any.

Most people should be able to get all vitamins, minerals and other nutrients they need by eating a balanced diet, without taking supplements. If you do choose to take supplements, speak to your doctor first and don’t take more than the recommended daily allowance (RDA).

Some men may need to take specific supplements. For example, if you’re on hormone therapy, your doctor might recommend calcium and vitamin D supplements. 

Herbal remedies

Some men like to take herbal medicines to help manage their prostate cancer or the side effects of treatment. For example, some men drink sage tea to help with hot flushes, which are a common side effect of hormone therapy. But there is very little evidence that herbal remedies can help to treat prostate cancer or reduce side effects.

It’s important to tell your doctor about any complementary therapies you are using, including herbal remedies. Some herbal remedies may interfere with your cancer treatment and some may affect your prostate specific antigen (PSA) level, making the PSA test unreliable.

Not all herbal remedies in the UK are licensed and the quality varies a lot. Be very careful when buying herbal remedies over the internet. Many are made outside the UK and may not be high-quality. Many companies make claims that are not based on proper research. There may be no real evidence that their products work and some may even be harmful. Remember that even if a product is ‘natural’, this doesn’t mean it is safe. For more information about using herbal remedies safely, visit the Medicines and Healthcare products Regulatory Agency (MHRA) website.

Herbal supplements being tested

Recently researchers have been looking at supplements containing a number of things such as pomegranate, green tea, broccoli, turmeric, soya and lycopene, to see whether they have an effect on prostate cancer.

There have been mixed results, with some studies suggesting they may be helpful and others suggesting they don’t help. These studies have all been small and run for a short time, so we need larger studies lasting for several years to find out whether any supplements actually help.

References

Last updated: May 2018

To be reviewed: May 2020