Tuesday, May 31, 2016

Which came first: Beer or wine? (or something else?)

Actually neither beer nor wine was the first fermented beverage, and wine arguably has a closer connection to health, but recent evidence indicates that humans developed the ability to metabolize alcohol long before we were even human. The uniquely human ability to handle alcohol comes from the digestive enzyme alcohol dehydrogenase, or ADH4. A new science called paleogenetics identifies the emergence of the modern version of the ADH4 gene in our ape ancestors some 10 million years ago. Interestingly, this corresponds to the time when our arboreal forebears transitioned to a nomadic lifestyle on the ground. We went from swinging from tree limbs to walking upright, and the rest is history. Understanding the circumstances that led to perpetuation of the ADH4 mutation may contain clues to what made us human in the first place.

How the ability to metabolize alcohol made us human

Paleogenetecist Matthew Carrigan has an idea about how this happened. Arboreal species rely on fruit that is in the tree, but if you can digest fruit that has fallen, and partially rotted – meaning fermented and therefore alcoholic – then you could get by just fine with less effort or when other sources of food were scarce. One simple mutation was all that was needed to impart this enhanced ability to metabolize alcohol, and this characteristic remains a defining difference between humans and other primates.

Why I think wine was first

One argument in favor of the wine first theory is that wild grapes, which grew on vines climbing trees (not the neatly trellised rows in modern vineyards), simply had to be gathered. Since wine could easily come from fermented fallen fruit, it could possibly go back millions of years, requiring only the ability to collect and store liquids. Fermentation happened automatically, so winemaking was more of a discovery than an invention. Physical evidence for early winemaking includes pottery fragments with wine residue that have been carbon dated to around 7400 years ago.
There is no direct evidence for beer making until at least 1000 years later. However, it has been theorized that a taste for fermented grain products may have prompted humans to begin farming around 10,000 years ago, because harvesting wild grains in sufficient quantities for brewing would be much less efficient than gathering fruit.  No hard evidence to support that idea has appeared, so the debate remains an open question.

About the only thing that we can be certain of is that the gathering of minds around shared drinks would lead to spirited discussions for millennia.

Thursday, May 19, 2016

More evidence that resveratrol is not the same as wine (and may be worse)

It has become common to think of the antioxidant molecule resveratrol as the main beneficial ingredient in wine, but a new study sheds light on how resveratrol without the other components of wine might actually be a bad thing. Sure, resveratrol is a miracle molecule, providing a plausible explanation for many of the health benefits of moderate drinking: lower odds of diabetes, cancer, osteoporosis, even longer life by activation of longevity genes. I leaned heavily on these findings in the book. But what I didn’t anticipate was that resveratrol would become such a hugely popular supplement, and in many people’s minds it became a proxy for wine. If a study showed some failing of resveratrol in a laboratory study, it was put out as a denunciation of healthy drinking. Or when it showed some positive effect in mice, it was hailed as proof that resveratrol had all the benefits of wine – without the alcohol. Both are oversimplifications.

Resveratrol works best when combined with other wine antioxidants

The first thorn in the roses is that in wine, resveratrol occurs in amounts usually much lower than those used in laboratory studies. Another is that in some studies it exhibits a phenomenon called hormesis, which means that different-and sometimes opposite-effects occur at different doses.  Consider also that resveratrol does not occur in isolation, but in combination with a range of antioxidant molecules called Wine-Derived Polyphenols (WDP). This latest study looked at the possibility that these are interrelated factors, by evaluating the antioxidant properties of resveratrol with and without WDP’s. The experiment used cells in culture that were subjected to ultraviolet light (in order to cause oxidative stress), with resveratrol added at varying doses with and without WDP’s.  They found that resveratrol had either pro-oxidant or anti-oxidant effects depending on dosage (confirming hormesis), but when WDP’s were added there was a synergistic antioxidant effect at all doses.

Whole wine better than resveratrol alone

The authors of this study concluded that resveratrol requires wine-derived polyphenols for optimum antioxidant efficiency, which implies that whole wine is a better choice than resveratrol supplements alone. The antioxidant properties of resveratrol are of course only a limited part of their repertoire, but given a choice I’ll go with the science on this one. To your health!