Today, medical researchers are painstakingly unravelling the causes and potential prevention measures for most cancers. The results strongly support the theory that the onset of cancer, a process whereby cells in our body begin to grow and multiply abnormally, is triggered by a combination of genetic and environmental factors such as pollution, carcinogenic chemicals (eg tobacco smoke), viruses, bacteria and in particular, diet.
Cancers that have been linked to diet include those of the mouth and throat, stomach, large bowel, pancreas, liver, gall bladder, lung, breast, womb, ovaries and prostate.
The main dietary factors associated with cancer risk are high fat or alcohol intake, high salt diets and low fibre intakes.
Any anti-cancer diet always relies on a major contribution from fresh vegetables, which have most of the nutrients which researchers now say can arm the body against the onset and the growth of cancer. It is believed, for example, that the beta carotene in red and yellow vegetables may play a major role in preventing cancer of the lung, breast, larynx, bladder, oesophagus, stomach, colon, rectum, cervix and prostate; that the antioxidant lycopene, in tomatoes helps reduce the risk of prostate cancer. Taking supplements to boost your intake is not recommended as it may have a damaging effect, and in some cases promote cancer.
Vegetables with high vitamin C prevent the formation of nitrosamines (possible carcinogens) from the nitrates in cured and smoked foods like salami and bacon. Other plant chemicals known as indoles found in broccoli, Brussels sprouts, cabbage and other cruciferous vegetables have been shown to affect oestrogen levels, which inturn potentially reduces the likelihood of developing breast tumours.
A high intake of the natural fibre which fresh vegetables deliver in abundance is believed to protect against diseases such as colon cancer. Perhaps just as important is the reality that high consumption of fresh vegetables means a lower intake of high fat foods, such as fast, convenience foods. A high fat intake increases risk for some cancers and adds excess kilojoules, which cause obesity - another key cancer risk.
For the typical Australian, the 6 rules (for reducing the risk of cancer) which we all need to remember when buying or eating foods are:
- Eat a balanced diet including all types of food but where fresh foods make up most of the menu.
- Eat considerably more vegetables and fruit in as wide a range as possible. (Most of us eat only around half the desirable amount.) Our diet needs to include lots of leafy greens(eg spinach and lettuce), yellow and red vegetables (capsicum, tomatoes and carrots) and crucifers (broccoli, brussels sprouts, cabbage) plus high mineral content tubers like potatoes.
- Avoid kilojoule dense foods such as fatty fast foods, soft drinks and biscuits. Control your weight carefully. Don't let kilojoules and calories get out of control.
- Avoid nitrates, cured and smoked foods (bacon, salami and preserved meats.)
- Be moderate with your alcohol intake. In today's high stress world, a little alcohol every day probably does more good than harm but the advantage quickly turns into a health problem when quantities are exceeded.