Best foods for cancer prevention

• Written by  Sade Oguntola
• Thursday, 06 February 2014 00:00

About 35 percent of cancers are related to nutritional factors. To help prevent cancer, experts have looked at a variety of foods rich in nutrients that individuals can easily incorporate into their diet and hopefully will keep them healthy for many years to come. SADE OGUNTOLA reports.
Eating plenty of fruits and vegetables daily is one of the tried and true recommendations for a healthy diet, and that for many good reasons. These ward off heart disease and stroke, control blood pressure, prevent some types of cancer and guard against poor sight due to cataract.
Over the past 30 years or so, researchers have developed a solid base of science to back up this recommendation. In fact, eating varieties of fruits and vegetables daily, numerous studies have revealed as protective against cancer.
A report by the World Cancer Research Fund and the American Institute for Cancer Research suggests that non-starchy vegetables—such as lettuce and other leafy greens, broccoli, cabbage, as well as garlic, onions, and the like—and fruits
“probably” protect against several types of cancers, including those of the mouth, throat, voice box, oesophagus, and stomach.
Specific components of fruits and vegetables, experts believe, may also be protective against cancer. For example, a research recommends increased consumption of tomato-based products (especially cooked tomato products) and other lycopene-containing foods may reduce the occurrence of prostate cancer.
 Lycopene is one of several carotenoids (compounds that the body can turn into vitamin A) found in brightly coloured fruits and vegetables, and research suggests that foods containing carotenoids may protect against lung, mouth and throat cancer.
Cancer is not a disease whose origin is principally genetic, as many people continue to believe, said Professor Femi Ogunbiyi, Director, Ibadan Cancer Registry.
According to him, it is a disease that is closely linked to a range of lifestyle factors, but which evidences are now suggesting simple things like increased consumption of certain fruits and vegetables and lifestyle modifications that include avoidance of smoking and obesity could be helpful in preventing.
Ogunbiyi, Vice President, African Organisation for Research and Training in Cancer (AOTIC), declared that eating varieties of fruits and vegetable is advocated because many contain fibre and other cancer-fighting substances.
He, however, cautioned that people should not assume that only foreign and expensive fruits and vegetables are protective against some cancers.
Ogunbiyi said: “We have enough fruits and vegetables in Nigeria that have similar things in them like apples, cucumber and cabbage that individuals could consume.
“Of course, eating fruits and vegetables would provide fibre to help increase the bulk for stool and increase transit time within the guts. This ensures that the guts are not exposed to cancer-causing substances that can make changes in the lining of the
guts.
“Fruits also provide vitamins, which are antioxidant substances that help to stabilise the body metabolism, so the most important thing is that people should eat the varieties of fruits and vegetables that are available because they are as useful to the body as those that are imported.”
Professor Ogunbiyi, however, declared that it was better for individuals to eat more fruits and vegetables in order to meet their mineral and vitamin body requirements rather than rely on the use of multivitamin supplements.
Here are fruits and vegetables evidences suggest are particularly good at protecting from cancer:

Carrot
Some studies suggest carrots protect against cervical cancer, perhaps because they supply antioxidants that could battle HPV (human papilloma virus), the major cause of cervical cancer.
 In fact, a substance called falcarinol that is found in carrots has been found to reduce the risk of cancer, according to researchers at Danish Institute of Agricultural Sciences (DIAS).
But cooked carrots is the best as it supply more antioxidants than raw, according to a report in the Journal of Agriculture and Food Chemistry.

Broccoli
Broccoli and other green leafy vegetables such as cauliflower, lettuce and sprouts are also rich in indole? compounds - plant chemicals which seem to modify oestrogen metabolism, decreasing the risk of breast cancer.
Two out of three studies examining the relationship between breast cancer and green leafy vegetables found that high consumption decreased the risk of breast cancer by 40 per cent.
According to research at Liverpool University, broccoli and other leafy greens contain a fibre rich in the sugar galactose, which could help prevent proteins called lectins from binding to the lining of the colon, and so decrease our risk of colonic cancer.

 Cabbage
An American study showed people who ate cabbage more than once a week reduced their chance of contracting bowel cancer by two thirds, though other studies haven’t shown such conclusive results. Some scientists think cabbage is particularly good at protecting against colon cancer and breast cancer.

Watermelon
Tomatoes, watermelons, guavas and grapefruit are rich in lycopene. More and more evidence is stacking up to suggest that lycopene might be a useful tool in the fight against a wide range of life-threatening conditions, including prostate cancer.

Garlic
Garlic battles bacteria, including H. pylori (the one connected to some ulcers and stomach cancer), and it reduces the risk of colon cancer. Several population studies show an association between increased intake of garlic and reduced risk of certain cancers, including cancers of the stomach, colon, esophagus, pancreas, and breast.
Also, an analysis of data from seven population studies showed that the higher the amount of raw and cooked garlic consumed, the lower the risk of stomach and colorectal cancer.
In fact, an Iowa Women’s Health Study said in the 1994 American Journal of Epidemiology that women with the highest amounts of garlic in their diets had a 50 per cent lower risk of certain colon cancers than women who ate the least.
But crushed garlic cloves are more effective than whole ones, as crushing helps to release the beneficial enzymes.

Tomatoes
The red colouring in tomatoes makes it a potential weapon against cancer. That red hue comes from a phytochemical called lycopene, a powerful antioxidant; several studies suggest reduce the risk of prostate cancer.
In laboratory tests, lycopene has stopped other types of cancer cells from growing, including breast, lung, and endometrial (in the lining of the womb). And they suspect lycopene stops the growth of tumours by interfering with abnormal cell growth, according to the American Institute for Cancer Research.
Tomatoes are also a good source of vitamins A, C, and E, all enemies of cancer-friendly free radicals.

Spinach
Spinach is rich in lutein and zeaxanthin, carotenoids that remove unstable molecules called free radicals from your body before they damage it. Some studies show these chemical substances could protect against cancer of the mouth, oesophagus, and stomach.

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An NIH/AARP study of more than 490,000 people found that those who ate more spinach were less likely to develop oesophageal cancer. Some studies suggest the carotenoids in spinach and other foods reduce the risk of ovarian, endometrial, lung, and colorectal cancer, too.

Beans
Beans, especially black and navy beans, increase levels of the fatty acid butyrate, which in high concentrations has protective effects against the growth of cancer cells.
According to a study from Michigan State University, black and navy beans significantly reduced colon cancer incidence in rats.
Another study, in the journal Crop Science, found dried beans particularly effective in preventing breast cancer in rats.

Walnuts
Phytosterols (cholesterol-like molecules found in plants)in walnuts  have been shown to block oestrogen receptors in breast cancer cells, possibly slowing the cells’ growth, says Elaine Hardman, PhD, associate professor at Marshall University School of Medicine in Huntington, West Virginia.
Sweet potatoes
Beta-carotene is a powerful antioxidant. Among premenopausal women, one study found that eating a lot of vegetables that include beta-carotene, folate, vitamin C, and fibre – like sweet potatoes — reduced the risk of breast cancer by about half.
Studies have shown that people who eat a diet high in beta-carotene have a reduced risk of cancer, particularly of the lung, colon, and stomach.

Soy beans
Soy beans help prevent prostate cancer by protecting the prostate from oestrogen which is harmful. Soy beans may be consumed in tofu, soy milk, or just regular soy beans.

Pineapple
 A delicious fruit, pineapple is a strong breast and lung cancer fighter. This fruit is an easy way to incorporate cancer fighting foods into your diet.

Apple
An apple a day keeps the doctor away is a phrase that is especially true when looking at the cancer-fighting and preventative powers of the apple. The apple helps prevent lung cancer and helps slow down the growth of prostate cancer.