Researchers have found evidence that our dietary choices have an impact on the risk, prevention, and progression of prostate cancer. However, deciphering all of the mechanisms involved in this effect is a huge task and one that is ongoing and still in its early stages. One of the areas under investigation is the association between methylation, diet and prostate cancer.
What is methylation?
Methylation is an epigenetic process that occurs when a methyl (CH3; one carbon atom bonded to 3 hydrogen atoms) group is attached to DNA. This activity changes or modifies the function of the genes and also affects their expression.
An epigenetic process is one in which the changes in organisms are caused by altering how the gene expresses itself rather than altering the genetic code itself. In basic terms, epigenetics involves turning genes on (making them active) or off (making them dormant).
Even though experts have not yet identified exactly how methylation works, its involvement in the metabolism of DNA and lipids appears to help prevent the expression of some cancer genes and cancer development. Some methyl-related nutrients have been associated with a reduction in the risk of some cancers (see “Methylation and diet” below).
Research on methylation and prostate cancer
Scientists have been on the trail of methylation and prostate cancer for some time. In a 2010 study, for example, investigators reported that “during cancer development and progression, tumor cells undergo abnormal epigenetic modifications, including DNA methylation,” and that use of demethylating agents was a potential treatment option for men with advanced prostate cancer.
Research also uncovered indications that modifications in DNA methylation patterns are detectable before the cancer becomes invasive, suggesting that “epigenetic changes are pivotal events” in triggering tumor development.
In a recent international joint study between researchers in the UK and Norway, the importance of DNA methylation in prostate cancer development was investigated. The experts reported that “DNA methylation changes are the most recurrent events so far identified in prostate cancer, and specific changes may associate with outcome.”
Although experts have not yet completely identified how methylation works, it is known that it is intimately involved in the metabolism of DNA and lipids and appears to help prevent the expression of cancer genes and thus development of cancer. In fact, methyl-related nutrients have been associated with a reduced risk of pancreatic, colon, prostate, and breast cancers.
Methylation and diet
Virtually everything you do can cause chemical changes around your genes that can turn them on or off during your lifetime. Some of those factors offer positive changes while others are negative. Diet, exercise, sleep, aging, socialization, smoking, alcohol use, where you live—all of these things and more can have an impact.
According to some experts, methylation can be reversed with diet, and more specifically, certain nutrients and bioactive food components. This effect seems to work by either directly interfering with the enzymes that trigger DNA methylation or by altering the supply of components necessary for the enzyme reactions to occur. These nutrients and bioactive food components include vitamin B6, vitamin B12, folate, choline, and methionine, as well as N-dimethyl glycine (DMG), S-adenosylmethionine (SAM-e; not available directly from food), and dimethyl-amino-ethanol (DMAE).
Foods that provide these nutrients are sometimes referred to as methyl donors. If you want to help have a positive impact on methylation, consider routinely adding the following foods to your diet:
- Choline: beets, broccoli, Brussel sprouts, cooked asparagus, cooked beet greens, raw cauliflower
- DMAE: anchovies, salmon, sardines
- DMG: beans, brown rice, pumpkin seeds
- Folate: chickpeas, citrus (e.g., oranges, grapefruit), leafy greens (e.g., bok choy, collards, kale, spinach), lentils, pinto beans
- Methionine: Brazil nuts, roasted soybeans, sesame seeds, tuna, white beans
- Vitamin B6: avocado, blackstrap molasses, grass-fed beef, pinto beans, pistachios, sesame seeds, sunflower seeds
- Vitamin B12: fish, organic meats, seaweed (laver and nori)
*Methylation and its role in prostate cancer is a controversial topic. Some of the substances named in this article (e.g., choline, folate) have been shown to support prostate cancer, while some experts have stated that methylation can be reversed with a diet that includes them. This article provides some science that seems to be contradictory to popular beliefs, and as such, warrants further investigation.
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