P53, where are you?

Don’t tell those purple pill people, but it’s selenium time again.

This has almost become an e-Alert tradition: every two or three months I find a new study that reminds us just how important it is to get adequate amounts of selenium in our diets.

In previous e-Alerts I told you how selenium helps fight autoimmune disorders, increase insulin efficiency, and curb the mutation of viruses. More importantly, selenium has been shown to reduce both the risk and mortality for prostate, liver and colorectal cancers.

Now another cancer can be added to that list: esophageal cancer – a disease closely associated with chronic heartburn and acid reflux.

The selenium millennium

When acid reflux causes digestive acids in the stomach to be regurgitated into the esophagus, damage to the lower esophagus often results in an abnormal healing process that causes the wrong type of cells to grow in the damaged area. This condition is known as Barrett’s esophagus. Painful acid reflux and heartburn symptoms may recede, but the new cell growth substantially increases the risk of esophageal cancer.

Knowing that elevated selenium levels may reduce the risk of other cancers, researchers at the Fred Hutchinson Cancer Research Center collaborated with a team at the University of Washington School of Medicine to study the relationship of selenium blood levels in Barrett’s patients. The Seattle Barrett’s Esophagus Program provided 399 subjects for the test – all diagnosed with Barrett’s. In addition to the analysis of blood samples and medical history, esophageal tissue specimens were collected and examined for DNA content.

Results showed a clear association between high selenium levels and a reduced risk that those with Barrett’s would develop esophageal cancer. More specifically, elevated selenium in the blood was associated with a significantly better chance that an important tumor-suppressing gene called p53 would be activated. (Just last year an Indiana University School of Medicine study showed striking evidence that selenium intake triggers activity of the p53 gene.)

These results are particularly significant because therapies have not yet been developed that would protect Barrett’s patients from esophageal cancer – a fast-growing cancer that is frequently fatal.

No fear of effective doses

All commentary about selenium inevitably comes with a warning about overdoing selenium intake, and the commentary I found for this study was no exception. In a Fred Hutchinson Cancer Research Center press release, the authors of the study warn that “megadosing” with selenium supplements is not recommended. And we would agree with that, but I would add this note: a toxic dose of selenium is hard to come by.

The U.S. RDA for selenium if 55 mcg, and the average diet probably falls short of that amount. I say “probably” because the selenium content of fruits and vegetables depends on the selenium content of the soil they’re grown in. In the U.S., selenium is most highly concentrated in the soil of six western states: North and South Dakota, Utah, Colorado, Montana and Wyoming. Anyone who lives in these states and eats large amounts of fruits and vegetables daily might be at slight risk of getting too much selenium, but only if they’re also taking a high dosage selenium supplement as well.

Dr. Martin L. Smith, the author of the Indiana University study on the tumor-suppressing p53 gene, noted that in order to reap the cancer preventive qualities of selenium, daily intake should be around 200 mcg. This is well over the RDA, of course, but you would have to get more than 2,500 mcg of selenium per day for an extended period to receive a toxic amount, so the chances of getting a dangerous dose are extremely slim.

Besides fruit and vegetables, bread, fish, and meat all contain selenium. The real selenium powerhouse, however, is the Brazil nut, weighing in at 840 mcg of selenium per ounce.

Not a minute too early

The authors of the Fred Hutchinson research state that it’s too early to recommend selenium supplements for Barrett’s patients, but I disagree. Supplements in moderate doses will not do any harm in the average person and the list of selenium’s benefits is long and impressive. So Barrett’s patients, as well as anyone with chronic heartburn or acid reflux, would almost certainly be giving themselves an important preventive benefit with a daily selenium supplement.

For further prevention of Barrett’s esophagus, those who are experiencing gastro-esophageal problems should talk to their doctors. For chronic cases, however, you want to avoid any over-the-counter antacids or prescription medications, which neutralize stomach acids. Those acids are there for a reason – we need them to digest food!

Anyone searching for a safe, effective, and inexpensive way to treat acid reflux and heartburn need look no further than the e-Alert “Fire Down Below” (12/23/02), in which HSI Panelist Allan Spreen, M.D., outlined a simple regimen that uses readily available acidophilus and digestive enzymes. Dr. Spreen’s protocol, when combined with a daily selenium supplement, makes for an effective plan that just might prevent the chain of events that leads to esophageal cancer.

To Your Good Health,

Jenny Thompson
Health Sciences Institute

“Serum Selenium Levels in Relation to Markers of Neoplastic Progression Among Persons With Barrett’s Esophagus” Journal of the National Cancer Institute, Vol. 95, No. 10, 750-757, 5/21/03, jncicancerspectrum.oupjournals.org
“Selenium May Inhibit Progression Toward Barrett’s-Related Esophageal Cancer” Fred Huctchinson Cancer Research Center, press release, 5/20/03, eurekalert.org
“What is Barrett’s Esophagus?” Johns Hopkins Pathology, pathology2.jhu.edu