Scientists more than ever now believe that many hidden secrets of cancer prevention may in fact lie in our dietary habits. Solid evidence is now available to support the theory that certain diets contain chemicals which can prevent or at least reduce the risks of certain cancers. The evidence does not depend on tests conducted on animals, but also on humans, and the results are quite convincing. Despite the large amount of information which scientists have accumulated on this issue during the past few years, they still have not reached the accurate results which may enable people to lead effective dietary habits against cancer. In fact, research on diet with relation to cancer is still in the early stages and may not show significant improvement before the coming ten years. However, scientists are quite optimistic about the results.

Obesity & Cancer

To start with, scientists tried to find a relation between obesity and certain cancers. They ended up with a strong correlation between overweight and esophageal cancer which usually kills its victims within six months of diagnosis (Raloff, p. 39). The study was conducted on 184 men and the results showed that the heaviest 25% of men in the study had more than three times the cancer risk of the thinnest quarter (Raloff, p. 39). However, the study also showed that those who ate the most fiber and most Vitamin C from vegetables were at half the risk of those who did not depend on fresh vegetables, regardless of their weight. In fact, those who depended on fresh vegetables and fruits seemed to have a 30 to 40% less risk than those who did not depend on these foods, regardless of their obesity (Raloff, p. 39).  These findings triggered further research on the effect of diet on cancer.

Fat & Cancer

Further studies showed that low-fat diet is highly related to a significant reduction of certain types of skin cancer. The Baylor College scientific team reported in 1994 that low-fat diets reduced the possibilities of sun-induced lesions (actinic keratoses) which usually lead to skin cancer (Berkeley Wellness Letter, p. 2). To state it in numbers, the report says that those who consumed low-fat diets faced a 30% risk of developing skin cancer compared to those who consumed diets rich in fat. However, this does not mean that the consumption of such diets will prevent cancer even with exposure to the sun (Berkeley Wellness Letter, p. 2).

The above results and those related to several other experiments lead to the same conclusion: that there is a significant relation between diet and cancer. Such findings are extremely important since by the year 2000 40% of the human population will develop cancer (Levine, p.6).

But how is our diet related to cancer? How can it cause it and how can it prevent it? The secret lies in two important factors, namely antioxidants and phytochemicals.

Antioxidants & Cancer Prevention

When we use up oxygen to burn food in our bodies into calories or energy. As a result of this natural combustion, organic by-products called free radicals are produced. These are toxic molecules which damage our cells and start carcinogenesis leading to tumors which in turn lead to cancers (Levine, p.6). The role of antioxidants is to look for these free radicals and destroy them to protect the cellular tissues in the body. Our bodies do not have enough anti-oxidants to fight free radicals, but fresh fruits and vegetables have them abundantly. This is why people who rely on fresh diet face less risks of cancer (Levine, p. 6). Among the foods that are rich in these antioxidants are citrus fruits, cantaloupes, peaches, strawberries,  broccoli, spinach, onions, whole-grain cereals, asparagus, cabbage, carrots, almonds and many others (Levine, p. 6). Many may be surprised when they find out that among the most popular antioxidants are Vitamin C, Vitamin E and beta-carotene.

Phytochemicals & Cancer Prevention

Phytochemicals on the other hand are neither vitamins nor minerals. They are compounds that are naturally found in plants such as fruits and vegetables, grains, legumes, herbs and seeds (Colino, p. 83). These powerful compounds are responsible for protecting the body against cancers, heart disease and even osteoporosis. Like antioxidants, they are available in pills in the supermarkets and drugstores. However, most scientists claim that pills are useless because they are still unable to detect the real factors which enable these compounds to prevent cancers. Perhaps the way they are found in nature is responsible for their effect and not their structure, which makes the pills useless ( Colino, p. 83).

Like antioxidants, phytochemicals have the ability to fight free radicals and consequently to protect the body against cancers. More than 200 studies have proved the ability of phytochemicals to cause a lower cancer risk in human bodies (Colino, p. 84).

It is quite evidence that phytochemicals prevent cancers to a great degree, but how they do it is what scientists do not know yet. There are plans to boost the amounts of these phytochemicals in plants through genetic engineering. Others have already extracted them and turned them to drugs and pills, although nothing has been proven about their adverse side effects or their potential to prevent cancers when they are manufactured in an industrial form (Colino, p. 84). The safest policy, scientists say, is to have between five and twelve servings of fruit at different times of the day. This would at least halve the chances of developing cancers such as breast, lung and colon cancers (Colino, p. 84). Scientists also advise people not to overcook their vegetables because they are not yet certain whether phytochemicals are able to retain their powers after being cooked. Instead, it would be better to use steaming, broiling, and microwaving  (Colino, p. 85).

The plants richest in phytochemicals are onions, garlic, scallions, yellow and red pepper, spinach, broccoli, cabbage, brussels sprouts, citrus fruits, concord grapes, green tea and certain vegetable oils (Levine, p. 6).

Fiber & Cancer Prevention

In addition to these important facts, doctors highly advise a high increase in the intake of fiber which helps the body eliminate wastes, but which also prevents the absorption of fat and cholesterol from the intestinal tract. Americans need this advise most because they only consume an average of 11 to 14 grams of fiber daily, whereas the recommended amount by the National Cancer Institute is 20 to 35 grams. On the other hand, doctors strongly recommend a decrease in the intake of fats to 20% or less of daily calories, whereas the daily fat consumption in the US is a dangerous 35% (Levine, p. 6).

Synthetic Chemicals vs. Fat

Here it is important to clarify a misconception that many people have carried for long. It was believed that eating fresh foods rich in fat is safer than eating canned food and the like. However, studies show today that overconsumption of fats found naturally in fresh foods is more related to cancers than the synthetic chemicals found in food supply (Consumer’s Research Magazine, p. 28).


Scientists have not yet found a drug or a natural cure for cancer, nor have they discovered means of prevention, but at least, they have discovered some significant ways of reducing the risks of various types of cancers. It seems that natural food will always prove itself to be the best thing to eat, not only because of its fresh taste, but also because of its ability to protect the body from diseases, especially cancers. We have every reason to believe that the next decade will witness a global return to eating fresh vegetables and fruits, and in large amounts.













Colino, Stacey. (March 1996). The disease-phyters. Women’s Sports and Fitness, v. 83, n.2.


Levine, Barbara. (October 23, 1995). Fighting cancer with a fork.  Newsweek, v.126, n.17.


Raloff, Janet. (January 21, 1995). Obesity, diet linked to deadly cancers. Science News, v.147, n.3.


What’s the threat of chemicals in food. (April 1996). Consumers’ Research Magazine, v. 79, n.4.