Saturday, October 30, 2010

Something new to chew on: Resveratrol chewing gum

My what a long way we have come since I first started lecturing and writing about wine and health a decade ago. For one, few had heard of resveratrol, the potent antioxidant in red wine, and many of those who had didn’t know how to pronounce it. Flash forward a few years and a few thousand research articles and now resveratrol is the flavor of the month, appearing in everything from diet pills to energy drinks. The discovery that it may activate the enzymes responsible for enhanced longevity normally associated with caloric deprivation catapulted resveratrol into the spotlight. Ads unabashedly tout it as the new fountain of youth. The latest version is a chewing gum, from a company called Gumlink A/S.

A few cautionary notes here, but there are also some good reasons why it might not be such a bad idea. Firstly, resveratrol hasn’t been able to explain all of the benefits associated with moderate wine consumption, and serious doubts have been advanced about whether it is truly capable of activating the longevity effect seen in lab experiments. So a healthy measure of skepticism is advised about any product, with or without resveratrol, that claims to deliver all the benefits of wine. But resveratrol is a remarkable molecule with many potentially useful capabilities for anti-aging. Several clinical trials are ongoing, though few have been completed.

So supplementation with resveratrol might not be a bad idea, we just don’t know enough to say for sure. One big problem with supplements is that resveratrol is poorly absorbed from the digestive tract, so most of it may be wasted. But research has shown that it is absorbed better from the lining of the mouth (oral mucosa) and I have speculated that wine drinkers who savor and swirl might be taking advantage of this without even trying. Another interesting line of research points to benefits of resveratrol in dental health. So assuming the resveratrol gum is sugar-free it just might be the ticket. Especially if it helps whiten those purple teeth from wine drinking.

Thursday, October 21, 2010

Wine and breast cancer: an update

With October being the annual exercise in breast cancer awareness, our attention turns to the ongoing issue of drinking and breast cancer risk. What we usually hear is the established advice that alcohol consumption in any form contributes to the risk of developing breast cancer, in a direct ratio of about one daily drink to a 10% increase. But if you have been following my posts here, you will know that the question of wine consumption and breast cancer is considerably more nuanced, and it remains entirely possible-even likely, in my analysis-that red wine decreases risk, in the right amounts. A recent study from the Fred Hutchinson Cancer Research Center here in Seattle, in collaboration with major cancer centers around the country, helps to shed some light on the subject.

But first we need to revisit the question of why alcohol could contribute to cancer in the first place. As I point out in my book, a scientifically provable basis for alcohol leading to the cellular changes that progress to cancer remains elusive. The best idea out there is that it somehow interacts with estrogen receptors, which would imply that only certain types of breast cancer (know as estrogen-receptor positive) would correlate with drinking. However, no large studies had previously looked at drinking and breast cancer subtypes before the recent Hutch project. What they found was a relationship of ER positive cancer only in an uncommon variant called lobular carcinoma, but not the much more common ductal type. This particular study did not evaluate subcategories of drinking, however, but it nevertheless raises more questions than it answers. Here’s why:

If alcohol contributes to breast cancer via the only plausible mechanism proposed, by interacting with estrogen receptors, the risk would not correlate only to an uncommon subtype that also happened to be ER positive. So we still lack a plausible cause-effect explanation for the role of alcohol in breast cancer. One reason why these studies give such conflicting results is the reliance on self-reporting, which is wildly unreliable when it comes to the question of drinking habits. Another is that drinking habits tend to be erratic; few have only wine, only a glass or two a day, and always with dinner. Studies from populations that do have more traditional wine drinking patterns show a reduction in breast cancer risk. As these populations become more and more modernized, the opportunity to get meaningful data from population studies diminishes. So pink may be the theme color for breast cancer awareness, but I prefer to call it rosé.

Tuesday, October 5, 2010

Wine and breast cancer risk with BRCA mutation

One of the more significant developments in the understanding of breast cancer risk factors was the discovery of two inheritable genetic mutations, BRCA1 and BRCA2, that dramatically increase the lifetime risk of breast cancer. These mutations are aberrant forms of a class of genes called “tumor suppressors” so when they don’t function normally, cancers are more likely to develop and spread. (Tests are available for these mutations and many women with BRCA are opting for prophylactic mastectomy and reconstruction.)

Since alcohol consumption is generally regarded as a risk factor for breast cancer, it is important to know how it might affect women with BRCA. Given all of the confusion about whether wine consumption increases or decreases risk, it becomes even more important to know what to recommend. Surely, the knowledge of a high risk of cancer and not being able to have a glass of wine with dinner seems like double punishment. Fortunately a recent study helps to provide some guidance.

The study, from a collaboration called the Hereditary Breast Cancer Clinical Study Group, analyzed matched pairs of breast cancer patients with and without each type of BRCA mutation, according to a range of lifestyle factors. It’s a powerful study because of the numbers of patients surveyed, nearly 2 thousand, and its broad reach from several countries, though most were from Canada and the U.S.

After statistical adjustments for other known factors, there was no increase in risk from moderate alcohol consumption. Some studies have actually found decreased odds of developing cancer among moderate drinkers with BRCA, but in this study the reduction was only seen in wine drinkers. The implication of this is that it is the wine that is responsible for lowering the risk seen in previous analyses where drinking could not be accurately subdivided by type of beverage. This meshes well with findings on breast cancer risk without the BRCA mutation.

Several compounds unique to red wine have impressive anti-cancer properties, specifically for breast cancer. Clinical trials using some of these compounds in conjunction with traditional therapy are underway. But if you or someone close to you has a strong family history of breast cancer, getting tested for the BRCA gene can save their life. The good news is that they can still share a glass of wine with you and not add to their worries.

Dennis J, Ghadirian P, Little J, Lubinski J, Gronwald J, Kim-Sing C, Foulkes W, Moller P, Lynch HT, Neuhausen SL, Domchek S, Armel S, Isaacs C, Tung N, Sweet K, Ainsworth P, Sun P, Krewski D, Narod S; the Hereditary Breast Cancer Clinical Study Group. Alcohol consumption and the risk of breast cancer among BRCA1 and BRCA2 mutation carriers. The Breast 2010;e-pub.