The American Cancer Society recommends that you eat at least five servings of fruits and vegetables daily. Some foods do have cancer-fighting properties, though experts haven't been able to confirm that they can prevent or treat cancer. But, research does show that the right kind of nutrition matters. According to Cancer Research UK, lab studies have shown that curcumin in turmeric has anti cancer effects. It seems to kill cancer cells and prevent more from growing. Cruciferous vegetables such as cauliflower, cabbage and broccoli contain sulforaphane compounds that have anti-inflammatory properties, as per America's National Cancer Institute. Experiments with animals have been positive, however, studies in humans have shown mixed results. According to a 2011 study by The Ohio State University Comprehensive Cancer Center, fish oil and fish contain omega 3 fatty acids which appear to stop or slow down the growth and development of breast cancer cells in laboratory studies of mice and breast cancer cells. Garlic battles bacteria. Its sulfur-containing compounds have a protective effect, say experts from the American Cancer Society. The World Health Organisation recommends that adults consume at least one clove of garlic daily to promote good health. In laboratory tests, lycopene in tomatoes has stopped breast and lung cancer cells from growing. Researchers speculate that lycopene protects cells from damage by boosting the immune system. It may stop the growth of tumours by interfering with abnormal cell growth, according to the American Institute for Cancer Research. Spinach is rich in lutein and carotenoids that may help remove unstable free radicals from your body before they damage it. A study of more than 490,000 people led by the National Institutes of Health in the United Stated found that those who ate more spinach were less likely to develop esophageal cancer. "It is not 100% certain that consuming more or less of certain foods or nutrients will guarantee cancer protection," clarifies Dr. Edward Giovannucci of Harvard's T.H. Chan School of Public Health. You must consult a medical expert before making any changes to your diet.