Dietary chemopreventive phytochemicals: too little or too much?
Some dietary phytochemicals seem to offer protection in an exposure-related manner and many molecular targets and signaling pathways affected by phytochemicals have been discovered.
Cancer Prev Res (Phila Pa). 2009 Jul;2(7):611-6.
Green tea (Camellia sinensis) for the prevention of cancer
Green tea contains catechins which are powerful antioxidants that may prevent cancer. This Cochrane review looked at 51 studies that included:
Drinking 3 to 5 cups of green tea per day is safe and provides 250 mg of catechins per day.
The author concludes that there is insufficient evidence for green tea consumption preventing cancer.
Cochrane Database Syst Rev. 2009 Jul 8;(3):CD005004.
Resveratrol: A Natural Polyphenol with Multiple Chemopreventive Properties.
Resveratrol, a naturally occurring polyphenol, shows pleiotropic health beneficial effects, including anti-oxidant, anti-inflammatory, anti-aging, cardioprotective and neuroprotective activities.
Curr Drug Metab. 2009 Sep 1.
Vitamin D for cancer prevention: global perspective
Can a daily dose of 2000 IU of vitamin D(3) reduce case-fatality rates of breast, colorectal, and prostate cancer by 50%?
A high consumption of fruit and vegetables was associated with a reduced risk of colorectal cancer; especially for colon cancer. The reduced risk was not seen in smokers.
Eating Your Veggies: Not As Good For You? – Time.
According to a report from the Journal of Horticultural Science & Biotechnology, vegetables today have up to 40% less minerals compared to 50 years ago.
What about vitamins?
Diet and cancer in Mediterranean countries: carbohydrates and fats.
Olive oil, and other mono- and unsaturated fats, appear to be favourable indicators of breast, ovarian, colorectal, but mostly of upper aero-digestive tract cancers. Whole grain foods are also related to reduced risk of upper aero-digestive tract and various other cancers. In contrast, refined grain intake and, consequently, glycaemic index and glycaemic load were associated to increased risk for several cancer sites. Fish, and hence a diet rich in n-3 polyunsaturated fatty acids, tended to be another favourable diet indicator, while frequent red meat intake was directly related to some common neoplasms. An a priori defined Mediterranean diet score was inversely related to upper digestive and respiratory tract cancers.
Public Health Nutr. 2009 Sep;12(9A):1595-600.
Bile acids are found in the bile and are stored in the gall bladder. Bile acid binding with steam cooked vegetables was measured in vitro. Increasing bile acid binding lowers cholesterol and this can reduce the risk of heart disease. Lowering bile acids may also reduce the risk of cancer. This study showed that steam cooking of vegetables increases bile acid binding.