Apples are a widely consumed, rich source of phytochemicals. Epidemiological studies have linked the consumption of apples with reduced risk of some cancers, cardiovascular diseases, asthma and diabetes. In the laboratory, apples have been found to have very strong antioxidant activity, to inhibit cancer cell proliferation, to decrease lipid oxidation and to lower cholesterol. Apples contain a variety of phytochemicals, including quercetin, catechin, phloridzin and chlorogenic acid, all of which are strong antioxidants.
National Public Health Institute in Helsinki, Finland
One of the studies referred to was conducted by the National Public Health Institute in Helsinki, Finland. It involved 10,054 Finnish men and women. This cohort epidemiological study researched the association between dietary intake of flavonoids and the risk of several chronic diseases. The researchers concluded that of all the main flavonoid sources, apple intake is associated with a reduced risk of almost all of the chronic diseases considered.
Overwhelmingly, the Finnish researchers pointed to the flavonoid quercetin, a plant-based phytonutrient found most abundantly in apples, onions, tea and red wine, as the flavonoid with the best potential health-promoting capabilities.
Furthermore, according to extensive research over many years, those study participants who ate the most apples and the flavonoid quercetin, had the lowest risk of total mortality; that is, they had the lowest risk of dying of any cause during the decades-long study.
Cornell University, USA
Research was conducted at Cornell University using Red Delicious apples grown in New York State to provide the extracts used to study the effects of phytochemicals. The researchers compared the anti-cancer and anti-oxidant activity in the apple flesh, and also studied the fruit’s skin.
Using colon cancer cells treated with apple extract, the scientists found that cell proliferation was inhibited. Colon cancer cells treated with 50 milligrams of apple extract from the skins were inhibited by 43 percent. The apple flesh extract inhibited the colon cancer cells by 29 percent. The researchers also tested the apple extract against human liver cancer cells. At 50 milligrams the extract derived from the apple with the skin on inhibited those cancer cells by 57 percent. The apple extract derived from the fruit’s fleshy part inhibited cancer cells by 40 percent.
A more recent 2005 Cornell Study, found that breast cancer incidence was reduced by 17, 39 and 44 percent in rats fed the human equivalent of one, three or six apples a day, respectively over 24 weeks.