A 2017 epidemiological study published in Frontiers in Oncology suggests that a diet rich in antioxidants like carotenoids and vitamin C can help to prevent breast cancer and lung cancer. Antioxidants have had their fair share of press in recent years and numerous studies have been done trying to pinpoint their perceived benefits. The good news is that those benefits are plentiful and getting enough of these powerhouse elements into one’s diet is easy as their sources are bountiful and delicious. But what are antioxidants? What do they accomplish in our bodies and how do these functions translate into cancer prevention?
Mention of antioxidants is usually in tandem with the term “free radicals.” Free radicals are highly reactive chemicals that have the potential and ability to harm cells. Their initial purpose is to aid in the metabolic processes, like digestion and converting food into energy. But when too many free radicals are produced, they can become a dangerous enemy.
Left unchecked, free radicals are capable of destroying enzymes, protein molecules and even complete cells. They can multiply by process of a chain reaction the byproducts of which are able to damage cell structures so profoundly that they compromise the immune system and even DNA codes are altered in a process called oxidation where they combine and react chemically with other molecules with which they were never meant to combine. Similar to a rusty nail in the rain, if the body’s cells go unprotected, impending and progressive damage occurs called “oxidative stress.” Free radicals accelerate the aging process by breaking down collagen, creating an aged appearance in the cells of our skin, eyes, tissue, joints, heart and brain. Since they react with oxygen, they lower the oxygen supply to cells and fuel systemic inflammation leaving our immune systems vulnerable.
What Antioxidants Do
Antioxidants include beta-carotene and other carotenoids such as lycopene, vitamins A, C, and E, and other natural and manufactured substances. They protect cells from damage because they inhibit oxidation in our bodies and are specifically used to counteract the deterioration of stored food products. In short, antioxidants are the anti-free radicals, keeping the latter from having the opportunity to interact with those molecules with which they were never meant to combine. In this way antioxidants help slow the aging process, reduce inflammation and boost our immune systems. All of these benefits lessen the oxidative stress on the body.
Key to Cancer Prevention?
There have been studies which have shown that antioxidant supplements like vitamins A, C, E, folic acid and beta-carotene can help reduce the risk for certain illnesses related to oxidative stress and that these include types of cancer. A 1993 clinical trial from China found what they termed “significantly reduced” stomach cancer mortality rates in those participants who took beta-carotene, vitamin E and selenium over five-years. However, just as readily as there are studies to support the cancer counter activity of antioxidants, you will find studies that prove they can do more harm than good.
Carotenoids, an antioxidant group including beta-carotene, lycopene, lutein and zeaxanthin, are highly bioavailable in many of the foods we eat. Whereas these elements have helped with the lessening of oxidation and address other damaging effects such as blue light’s effect on the eyes, excess consumption or supplementation of these in the systems of those predisposed to or with lung cancer or mesothelioma has shown to yield adverse events.
For better or worse, the hunt for concretized proof continues as to whether or not antioxidants or, more specifically, supplements thereof, can impede the proliferation of cancer cells. Information from recent clinical trials is less clear as, in recent years, large-scale and randomized studies have reached only inconsistent conclusions. What is known is that the intake of foods already rich in antioxidants, consumed according to current dietary recommendations, does suppress free radicals. This suppression keeps the levels of inflammation lower, slows aging in the skin, eyes, tissue, joints, heart and brain, allows the immune system to function more optimally and keeps the body more consistently oxidized and refreshed.
Former National Foundation for Cancer Research (NFCR)-sponsored researcher, Dr. Helmut Sies, is a physician, scientist and a pioneer in redox biology. He is a leader in the study of carotenoids in plants and how they protect the skin and other organs from free radicals. In 1985, Dr. Sies first coined the term “oxidative stress” in a landmark paper. In 1989, he discovered that lycopene—the carotenoid antioxidant found in tomatoes and carrots—exhibits the highest antioxidant activity and singlet oxygen quenching ability of all dietary carotenoids. Lycopene has strong skin cancer prevention effects. Its antioxidation effects are greatest when tomatoes are processed as in a paste or sauce and combined with oil for the best bioavailability. Dr. Sies’ research also illustrated how flavonoids (found in cocoa products) can prevent skin damage caused by ultraviolet radiation, improve blood vessel function and reduce cardiovascular risk.
In 2013, Dr. Helmut Sies was awarded the Linus Pauling Institute Prize for Health Research, an honor that recognizes excellence in research relating to the roles of vitamins, essential minerals and phytochemicals in promoting health, and preventing or treating disease. The National Foundation for Cancer Research is proud to have sponsored the research program of Dr. Sies and his team from 1983 to 2016.