Dieting and Decompression: Unchartered Waters.

[Roger Hobden]

Hello, with this thread I simply wanted to point out this article that was published in Nature on the 4th of July 2018, and that I believe would be of general interest to the diving community at large.

Article | OPEN | Published: 04 July 2018
Stimulating fermentation by the prolonged acceleration of gut transit protects against decompression sickness

• Sébastien de Maistre,
• Nicolas Vallée,
• Sandrine Gaillard,
• Claude Duchamp &
• Jean-Eric Blatteau

Scientific Reports volume 8, Article number: 10128 (2018) |

https://www.nature.com/articles/s41598-018-28510-x

In recent years, there has been a lot of peer-reviewed research drawing attention to the fact that the content of the human microbiome inside of the gut may have an significant impact on brain function.

This raises many interesting questions:
Do certain bacteria inside the gut have a protective versus a predisposing effect on decompression sickness ?
Does diet composition, either immediately, or on the long terme, have any of these effects ?
Are these effects mediated through physio-chemical means, or through an epigenetic mechanism, or though neurological connections between "the brain of the gut" and the central nervous system ?
Etc.

The practical impact on day to day diving would be to either recommend or avoid certain foodstuffs, possibly individualized depending on the bacterial make-up of of the microbiome of each individual diver.

"Preventative precision-dive medicine ", if you will.

Food for thought.

 

[tridacna]

Amazing. I thought that this may have been a candidate for an Ignobel. But it’s in Nature!

Keen to hear what Simon thinks of this.

 

[VE7DAC]

It looks like their primary concern was the hydrogen produced by bacteria in the gut while at depth, and the difference between the control and test groups was being fed Propylene Glycol (a laxative) for a week before the dry dive.

There was a small sample size, but the results are very interesting. This study supports the idea of being in good general health (and not constipated) for diving.

Maintaining a high fiber diet increases bowel motility and digestive transit speeds in much the same way as the PEG used in the study, without the unpleasant side effects. It's also good for your general health. Knowing it might mitigate the effects of DCS is just another reason to maintain a healthy diet.

Is anyone aware of other studies relating to hydrogen's affect on DCS? This is the first I've heard of a link between them.

 

[dberry]

Study performed on rats... they must have been adorable with their tiny wetsuits and regulators.

BTW, the polyethylene glycol (PEG) used as a laxative for the rats is the active ingredient in over-the-counter "Miralax" (for people).

 

[dberry]

<snip>
Is anyone aware of other studies relating to hydrogen's affect on DCS? This is the first I've heard of a link between them.

The Nature article mentions some references linking gut fermentation to increased rates of DCS; I didn't pull the references, so I'm not sure they link the DCS to hydrogen.

de Maistre, S. et al. Gut fermentation seems to promote decompression sickness in humans. J Appl Physiol (1985) 121, 973–979 (2016a).

 

[Bubblesong]

Since I eat lots of fiber, take fiber supplements, eat fruit and veggies and Activia probiotic yogurt, and still find myself with enough gas to live my life as a Walking Whoopi Cushion, I read this article looking for the takeaway on what to do about preventing DCS. Here is the section that says, eat fiber and laxatives for week or two before diving, then day before dive eat light, less fiber: Their words:
“Despite being detrimental in the short term, i.e., at the time of diving, gut fermentation apart from dives might have a positive effect by preventing the occurrence of DCS and limiting its severity (Fig. 6). Thus, it might seem wise to reduce consumption of foodstuffs with high fermentation potential the day before a dive.”
ALCOHOL: red wine and liquor on the rocks are recommended as least gas inducing according to this article:
https://m.huffingtonpost.com.au/201...ng-alcoholic-drinks-youre-welcome_a_21602777/

 

[MargaritaMike]

ALCOHOL: red wine and liquor on the rocks are recommended as least gas inducing according to this article:
https://m.huffingtonpost.com.au/201...ng-alcoholic-drinks-youre-welcome_a_21602777/

Other than the fact that it's stated in Huffington Post, it looks like all my margaritas need to be on the rocks and not frozen. Things that make you go Hmmm!

Cheers