There's much passing reference to the need to eat more vegetables so that you can avoid cancer, but beyond the urging of some health promotion staff little seems to be designed in the lay press in any detail at all. The simplistic message is out there and many doctors don’t yet recognize the need for diet in relation to reducing the chances of the disease occurring or for the care of patients who already have cancer. They do not recognize that good nutrition is a natural cancer treatment.

Many doctors are wedded to the fast effects of antibiotics. They really want any and every drug to be just as effective as antibiotics were when first being used. And if foods cannot give that sort of effect with nearly all people then a goodly number of them will dismiss the impact of food as being "probably not important".

However, there are lots of drugs that are not very effective. Chemotherapy increases survival overall on the 5-year stage by only just over 2%, with it being ineffective in many cancers, despite its ongoing use. With this in mind, any "natural" activity without negative side effects should be embraced with open arms.

There are many foods which have been shown in epidemiological studies to reduce the chances of getting cancer by 25%, 50%, 75% and sometimes even more when you compare high consuming groups with low consuming groups.

You will find foods which seem to prevent cells from mutating into cancer cells. There are foods which encourage mutated cells to die off. There are foods which stop the cancer cells from growing, or reduce the speed of growth and foods which stop the cancer cells from moving around the body. In biomedical terms, foods can be antioxidant, anti-inflammatory, anti-carcinogenic, anti-mutagenic, encouraging apoptosis, cytotoxic, with antimetastatic effects. Fruits and vegetables can have all of these effects.

What are the main vegetables and fruits? Maybe suggest using variety and not get hung up on just one or two thinking that will be enough. Plants act synergistically, that is they work better when you eat a number of them together.

With that said, the onion family are reported to have some of the strongest effects in preventing cancer. As I traveled through the medical literature there was a huge interest in tomatoes and the cruciferous vegetables, but when I compared the numbers in the studies it seemed that onions, garlic yet others in the allium family (like leeks and chives) had the greatest effect.

Tomatoes are good and so are the cruciferous vegetables - cabbage, red cabbage, cauliflower, broccoli, arugula, beet greens, bok choy, brussels sprouts, collard greens, garden cress, horseradish, kale, kohlrabi, radishes, rutabaga, Swiss chard and turnips.

Lettuce, carrots, summer and winter squash, oranges, lemons, blueberries, dark raspberries, grapes, cucurmin (of curry fame) and herbs (such as oregano, rosemary and thyme) have all proven to improve immune functioning and are associated with reduced numbers of cases of cancer in epidemiological studies.

What exactly does this mean in practice? Ideally fresh fruit and vegetables should be part of every meal. If you can't make it three meals a day, then settle for fruit and vegetables taking up the vast majority of your plate at two meals each day.

We are referring to eating - this is not medicine, except that these foods do you good. It is important to choose foods that you enjoy. I really do not like curries or pepper. I do not do well on Indian food, so I do not eat it very often. I had been brought up on North European foods and enjoy those fruit and vegetables my family has eaten for generations. So start by eating fruits and vegetables you enjoy, then go for a little variety and try some that are new to you.

If you are wedded to fried chips, packaged foods and hamburgers it might take a little getting used to have three quarters of your plate with fresh vegetables (cooked and raw) with fruit for dessert, but give it a go. It might take a few weeks for you to develop the enzymes needed to digest your new diet, but one that happens, your body will love you for this change. A natural cancer treatment it is both enjoyable and of no more cost than other types of eating.