February 4 is the World Cancer Day. World Health Organization reports that 14,000,000 people are diagnosed with cancer each year and about 8,200,000 dies from cancer and its complications annually.  In the next 20 years, cases of newly diagnosed cancer are expected to increase 70% and without effective treatment, the death toll from cancer would increase to 13 million from 8.2 million. 

Although cancer is a common chronic disease, at least one thirds of cancer can be prevented by simply following a healthy lifestyle including reduced alcohol consumption, healthy eating, and increased physical activity.  If smoking tobacco can be avoided or reduced, 50% of cancer cases can be prevented.

Specifically, the following 12 things to do or not do may help prevent or reduce your risk of cancer.

1,  Keep windows open for at least half an hour per day.

This is not only important for people in countries where indoor polluting chemicals are commonly present at home.    Radon and other radioactive particles released from household/construction materials and floor and the environment can increase the risk of lung cancer.  The U.S. Environmental Protection Agency says that the indoor air quality can be 10 times worse than that of the outdoor air.  Keeping windows open for at least 30 minutes can reduce the radioactive particles indoors to the outdoor level.  About 8% people are expected to be diagnosed with lung cancer in the United States, according to the Centers for Disease Control and Prevention.  

2, Use dry towel to rub the back

This is a very common practice in Japan (Note that the Japanese live a few years longer than the Americans while they do not invest as much on healthcare).  Research at Tokyo University indicates that this practice can be protective against cancer because it can generate heat on the skin which can activate a type of cell in the muscle under the skin to kill cancerous cells.

In fact, any work on the back is beneficial to the mid-aged or older people.  Use whatever available to generate some heat on the back until the skin becomes "red and hot".

3,  Eat onion and garlic as part of meal

In China, the lowest incidence of gastric cancer or stomach cancer is found in a Shandong Province where garlic and onion are most commonly used.  On average, people there eat six kilograms of garlic each person each year.

The reduced cancer risk has something to do with anti-oxidative allicin which can lower the carcinogenic nitrosamine level in the body.  Research shows that people eating the highest amount of garlic are at 60% reduced risk for cancer, compared with those who eat the lowest amount.  Allicin is formed after garlic is crashed and this compound is thermally unstable.  For that reason, it is advisable that people should eat freshly crashed garlic, which can be used along with other foods or salad.

4, Drink soy milk

In the Food Safety textbook used in the United States, soybean is labeled as a bad food that is full of toxicants.  The biggest concern is its phytoestrogens.  However, American Institute of Cancer Research points out that women who drink soy milk have their breast cancer significantly reduced.  The possible explanation is that the phytoestrogens, which are often weaker in terms of their potency to promote cancer than the endogenous estrogen can reduce the promotional effect of estrogen on the growth of breast cancer.  For that reason, soy milk may help reduce the risk for any cancer that is responsive to estrogen such as breast cancer, prostate cancer, ovarian cancer and other female reproductive cancers.  However, some doctors caution that cancer patients should avoid soy milk because it has a cancer-promotional effect.  People with gastric ulcer or gastritis or other cancers need to reduce or avoid consumption of soy foods.

5,  Walk one hour a day

The magazine Reader's Digest once reported that walking 30 minutes after meals every day or 4 hours per week can halve the risk of pancreatic cancer.  Harvard University conducted a study and found walking one hour a day cut risk of colon cancer by half.

One reason for the benefit is that the risk of pancreatic cancer is higher in people with high body energy. Walking can use up excess energy and prevent pancreatic cancer.   Physical excise can also help because it can get rid of some cancer-causing heavy metals through sweats.

Exercise can also lower estrogen and help reduce risk of breast cancer in women.

6, Drink 6 glasses of water (1.4 liter or 47 ounces of water)

The New England Journal of Medicine reports that drink 6 glasses of water (6x240 grams or 1.4 liter or 47 ounces of water daily may reduce the risk of bladder cancer by 50% in men and colorectal cancer by 45% in women.

Drinking water increases the volume of urine, which can carry away some harmful chemicals like urea and uric acid, which can otherwise irritate the bladder and the colon, some doctors explain.

7, Expose to the sun 15 minutes a day

Vitamin D deficiency has been associated with more than 100 health conditions such as cancer, metabolic syndrome, depression, autism, diabetes and cardiovascular disease.  Exposure to the sun is the cheapest way to acquire vitamin D.  Exposure of bare hands and face to the sun at the hottest hours of the day can make us up to 10,000 IU of vitamin D.  An increasing body of evidence suggests that vitamin D is protective against cancer such as breast cancer, colon cancer, prostate cancer, ovarian cancer and stomach cancer.  Vitamin D has been known to help prevent viral infection such as flu and colds as this “vitamin” is involved in the making of antibacterial  peptides, which are important for immune functions.

8,  Drink 4 cups of green tea

There is no doubt that drinking green tea prevents cancer.  A 9-year study conducted in Japan shows that drinking 4 or 5 cups of green tea, which is popular in Japan and China and other Asian countries, is associated with 40% reduced risk of cancer.

Professor Han Zhi from the Center of Nutrition and Food Safety, part of The Chinese Centers for Disease Control and Prevention has conducted research on tea for 17 years and found that oolong tea, green tea and black tea render a substantial preventative effect on oral cancer, lung cancer, esophageal cancer and liver cancer.  Particularly, green tea such as Longjing, Biluochun and Maofeng (famous brands of green tea in China) contains 5 times higher anti-carcinogenic ingredients than other teas.

However, it should be remembered that pone should not drink tea with high amounts of extract or high concentrations of extracted tea ingredients or at very high temperature.   Tea is best brewed for 5 minutes and drunken at 60 oC (anything can burn the lip when the temperature exceeds 60 oC).

9,  Chew each bite 30 times before swallowing it

People have high risk for stomach cancer if they do not chew foods enough.  Chewing can help digest foods and reduce the burden of the stomach and reduce the risk of gastrointestinal cancers.  Studies conducted by University of George scientists have also suggested that saliva possesses a potent detoxification effect and completely deactivates aflatoxin B in 30 seconds.  Aflatoxin B can cause liver cancer.  Alfatoxin B is found in crops like peanuts and corn that get molds.

Additionally, slow eating prevents overeating.  So this practice may also potentially help prevent obesity.

10,  Sleep 7 hours a day

American Institute of Cancer Research has studied and found that women who slept less than 7 hours a day were 47% more likely to develop breast cancer, compared with those who slept 7 or more hours per day.

Men and women produce melatonin when they sleep. Melatonin slows down the production of the female hormone estrogen, which is known to promote the development of breast cancer and others.

It is best for men and women to go to bed before 11:00.  For older men and women, the best time for them to go to sleep may be before 9:00.

Also having a nap at 13:00 pm can enhance the immune cells, which can protect against cancer.

11, Eat less sugar

Cancer cells like sugar or the best food for cancer is sugar.   A Japanese book titled "How to Prevent Cancer" points out that when the blood passes through a tumor, about 57% of the blood sugar will be consumed by the cancerous cells.

American Journal of Clinical Nutrition suggests that drinking a cup of sugar sweetened beverages increases risk for pancreatic cancer by 90%.  Some doctors suggest that it is best not to eat any added sugar at all.  Those who could not avoid sugar should limit their intake of sugar to 50 grams a day.

12,  Drink a glass of red wine when eating meat

Cooked meat, particularly processed red meat can have substantial amounts of carcinogens or chemicals that promote cancer development.  Preservatives, thermally generated carcinogens, heme iron in meat can all increase the risk of cancer.  Resveratrol, an antioxidant found in red wine and red grapes, peanut skin, is protective against gastrointestinal cancer.  Drinking an orange juice with high vitamin C may also help prevent the formation of carcinogens called nitrosamines.

The American Institute of Cancer Research suggests that no more than 500 grams of pork, beef, and lamb meat per week should be consumed.  High intake of red meat can increase colon cancer. (Edited by David Liu)