Friday, January 18, 2013
‘A jug of wine, a loaf of bread — and thou.”
The Persians — current day Iranians — loved their poets and, apparently, their Shiraz wines. The origin of the grape is controversial. Some insist the grapes came from the great city of Shiraz, near the heart of the Old Persian Empire.
From my time in Iran, I recall the pride villagers took in the number of very old people they produced. It would be great for Walla Walla if we could prove a $60 Cabernet guaranteed 100 years of fruitful life.
First, let’s consider wine and colon cancer, the malignancy that has given us insight into other malignancies.
Resveratrol, Res for short, is a chemical found in the skin of red grapes and on the shelves of pharmacies and hucksters. For the last few years it has been promoted as the answer to longevity.
If you believe in simple answers, you don’t enjoy my columns. The resveratrol link with colon cancer is promising, but you know that I won’t tell you that it is a cure that’s being suppressed by Big Pharma. The industry has committed only some of the sins that it’s blamed for.
The technical stuff: Studies published in the journal Proteome Science in 2011 show high doses of Res suppress colon cancer cell proliferation and promote apoptosis. High dose levels are achievable in the colon, possibly best if linked to a chemical that protects it from enzymes in the upper intestine.
Res acts through more than one pathway to protect against or do battle with colon cancer. One effect is the interaction with p53, discussed in a previous column. Another factor involves the IGF, insulin growth factor system. IGF promotes colon cell growth and it is associated with obesity. Obesity, in turn, increases the risk of colon cancer. The chemical links form a spider web of threads that laboratories around the world are sorting out.
At this point, I have submitted my body to colonoscopic screening. I also take small, uncoated aspirin each day, and I walk past the Resveratrol display. I understand that red wine contains a lot more chemicals than resveratrol.
Alcohol usage represents a medical and societal problem. Some studies indicate that it adversely affects women more than men. There is a suggestion of a net benefit if men drink up to two standard drinks a day. Ladies, consider sticking to one.
Omar Khayyám paints an enticing picture, but he should have had less than a jug of wine. If you want eternal youth from grape skins, be aware.
Res makes chemical changes that should make rats live longer, but it’s not happening, not yet, anyway. The other important reminder is that most supplements fail to survive the corrosive test of time.
Some are found to have effects opposite what we expected. I was once involved in an experiment to boost the immune system of lung cancer patients. The treated patients began dying sooner than the untreated ones, and we blew the whistle on the idea.
We are complex beings, full of feedback loops, surprises and challenges. We humans are built to take on challenges. Embrace the need to understand ourselves and our world.
What about other ways to protect ourselves?
Statins are used as protectors against cardiovascular disease. There is evidence that they slow progress of some malignancies and lower death rates from cancer, including metastatic breast and prostate. They are not useful prophylactically and they carry a variety of risks. It’s possible they decrease the cholesterol needed for cell growth. (New England Journal of Medicine, Nov. 8, 2012.)
Vitamin D results are mixed. Sun exposure is associated with lower cancer risks, other than skin. Blood levels have been inversely related to colon cancer, but data is uncertain. The National Institutes of Health are conducting a large, expensive study. Results are expected in 2017. Vitamin D has some toxicity potential.
Other vitamins — There are reports of reduced polyp recurrence with vitamins C and E and beta carotene. Early reports of effective treatment with high doses of C have not been supported by evidence. A high level of antioxidant vitamins in a normal diet is associated with a lower risk of cancer.
Randomized studies using supplements haven’t supported their value, although there has been evidence of reducing colon polyps. The explanation may point to a difference between eating fruits and vegetables and taking pills. The length of follow-up and other factors could account for the disconnection.
Epidemiological studies hint of a relationship between selenium intake and inhibition of colon cancer. Again, there are lifestyle factors that complicate data interpretation. Calcium [2+] can slow proliferation of colon cells, but it may have the opposite effect when cancer has developed.
Confused? Me too. Patients have expected me to have better answers. I have only a few.
Try this: Eat your fruits and veggies, exercise, and do everything your mother said, except, “Clean your plate.”
Dr. Larry Mulkerin is a retired clinical professor. He can be reached at firstname.lastname@example.org.