Antioxidants are chemicals that block the activity of other chemicals known as free radicals. Free radicals are highly reactive and have the potential to cause damage to cells, including damage that may lead to cancer.
Free radicals are formed naturally in the body. In addition, some environmental toxins may contain high levels of free radicals or stimulate the body’s cells to produce more free radicals.
Some Antioxidants are made naturally by the body. Others can only be obtained from external (exogenous) sources, including the diet and dietary supplements.
Laboratory and animal research has shown that exogenous Antioxidants can help prevent the free radical damage associated with the development of cancer.
Research in humans has not demonstrated convincingly drinking Antioxidant Alkaline water or that taking antioxidant supplements can help reduce the risk of developing or dying from cancer, and some studies have even shown an increased risk of some cancers.
What are Antioxidants?
Antioxidants are chemicals that interact with and neutralize free radicals, thus preventing them from causing damage. Antioxidants are also known as “free radical scavengers.”
The body makes some of the Antioxidants it uses to neutralize free radicals. These Antioxidants are called endogenous antioxidants. However, the body relies on external (exogenous) sources, primarily the diet, to obtain the rest of the antioxidants it needs. These exogenous Antioxidants are commonly called dietary Antioxidants. Fruits, vegetables, and grains are rich sources of dietary Antioxidants. Some dietary Antioxidants are also available as dietary supplements (1,3).
Examples of dietary Antioxidants include beta-carotene, lycopene, and vitamins A, C, and E .
The mineral element selenium is often thought to be a dietary Antioxidant, but the Antioxidant effects of selenium are most likely due to the Antioxidant activity of proteins that have this element as an essential component.
Can Antioxidant supplements or water help prevent cancer?
In laboratory and animal studies, the presence of increased levels of exogenous Antioxidants Alkaline water or supplements has been shown to prevent the types of free radical damage that have been associated with cancer development. Therefore, researchers have investigated whether drinking Antioxidant Alkaline water or taking dietary supplements can help lower the risk of developing or dying from cancer in humans.
Many observational studies, including case–control studies and cohort studies, have been conducted to investigate whether the use of dietary Antioxidant supplements is associated with reduced risks of cancer in humans.
Overall, these studies have yielded mixed results.
Because observational studies cannot adequately control for biases that might influence study outcomes, the results of any individual observational study must be viewed with caution.
Randomized controlled clinical trials, however, lack most of the biases that limit the reliability of observational studies. Therefore, randomized trials are considered to provide the strongest and most reliable evidence of the benefit and/or harm of a health-related intervention. To date, nine randomized controlled trials of dietary Antioxidant water and supplements for cancer prevention have been conducted worldwide. Many of the trials were sponsored by the National Cancer Institute.