Historically, alcohol was used to treat bends in Greek sponge divers. In the late 1980s attempts to verify the possible beneficial effects of ethanol on prevention of decompression sickness (DCS) led to prevailing opinions that there was no proven benefit and that divers should not drink and dive. On the other hand, the assumption that wine drinking has beneficial effects on general health is still propagated.
The so called “French paradox” fueled a search for possible healthful components in wine that, as some researchers posted, protect French people from heart disease despite their fat-rich diet and high blood cholesterol levels. Tannins and phenolics, a large group of substances that together make up to 0.1 percent of wine mass and determine the color and the taste of wine, were identified as beneficial substances. The most intriguing and studied phenolic is resveratrol which is now also sold as a dietary supplement.
Studies of resveratrol in vitro (on cellular cultures or in various models of biochemical systems) have shown anti-oxidant and other effects that with basic biological processes may provide protection against aging, various diseases and death. Further animal studies appeared to confirm beneficial effects. Some of the suspected mechanisms involving resveratrol included functions of endothelial cells (inner lining of blood vessels) and platelets which are also affected in diving. If resveratrol could prevent endothelial cell dysfunction and platelet aggregation, it may help to avoid decompression sickness. Recent resveratrol studies claimed several additional health benefits that could be appealing to divers.
The first claim is that resveratrol has beneficial effects on skeletal and cardiac muscle functions similar to what is seen with endurance exercise training.1 Wouldn’t it be nice to work on your fitness by relaxing and sipping wine after a long workday rather than going to the gym and sweating?
The second claim is that resveratrol improves brain perfusion and provides neuroprotection,2 both of which may be helpful in reducing risk of decompression sickness. Why not drink wine before or after diving?
Unfortunately, there is only one problem with all these studies; the amount of resveratrol used is equivalent to drinking 50 to 3,000 liters of wine per day. It is far more than is needed to get drunk. It’s enough to dive in. Thus, drinking red wine does not seem to be a practical prophylaxis of decompression sickness.
But don’t despair. Even French Paradox is not due to wine drinking as was believed forty years ago. Most population studies indicate that health and longevity may be associated with overall diet. The benefits of French diets appear to come from plenty of fresh vegetables, moderate caloric intake and physical activity rather than just from wine. The French diet has a lot in common with the so called Mediterranean Diet which is widely considered most favorable. In fact, in 2010 it was acknowledged by United Nations Educational, Scientific and Cultural Organization (UNESCO) as an Intangible Cultural Heritage of Humanity.
This story illustrates a common wisdom that there is no one single dietary supplement that could provide what mortals want. To stay healthy and fit for diving, adopt a healthy diet3 and, if you drink wine, limit yourself to one glass with your meal. More importantly, do not drink before the dive.
References
- Dolinsky VW, Kelvin E. Jones EJ, Robinder S. Sidhu SS, Mark Haykowsky M, Michael P. Czubryt MP, Tessa Gordon T, and Jason Dyck. Improvements in skeletal muscle strength and cardiac function induced by resveratrol during exercise training contribute to enhanced exercise performance in rats. J Physiol590.11 (2012) pp 2783–2799.
- Otto MA. Resveratrol improves cerebral perfusion in type 2 diabetes. Clinical Endocrinology News Digital Network. January 17, 2016.
- US Department of Health and Human Services and US Department of Agriculture 2015 – 2020 Dietary Guidelines for Americans. 8th December 2015.