University of South Florida associate professor Joseph Dituri holds the record for living the longest underwater. He spent 100 days living in a 100-square-foot habitat 22 feet under a lagoon in Key Largo during the spring. The pressure on the body at that depth is 70 percent higher than that on land, and Dituri, who has a Ph.D. in biomedical engineering, says the experiment improved his sleep, enhanced his brainpower and decreased the chance of inflammation in his body, among other benefits.
While living in the Jules’ Undersea Lodge, Dituri, 55, whose nickname is "Dr. Deep Sea,'' conducted experiments daily and taught lessons to more than 5,500 students from throughout the world. Dituri, a retired U.S. Navy Commander whose specialty was deep submersibles, will speak about the experience in a lecture at Harbor Hall Auditorium on the USF St. Petersburg campus on Wednesday, Oct. 11, at 6 p.m.
His talk is presented in conjunction with the USF Contemporary Ary Museum Generator exhibition “Superflex: This Is The Tip Of The Iceberg,” which is currently on display in the gallery at Harbor Hall. The talk is free and open to the public.
Dituri talked with 83 Degrees about his experiences living underwater.
Did you get stir-crazy during the 100 days underwater?
No, I wasn’t getting stir crazy. I felt really great. I did miss my family. I have three daughters. I missed the girls. I certainly missed my girlfriend, obviously. I missed the human touch as well. You’d be surprised at how many times you meet someone and shake their hand, pat them on the back, give them a hug, doing that everyday.
How did you spend the days?
I did my biomedical engineering – blood, urine, saliva, electrocardiogram, electroencephalograms, pulmonary function test. I did all that for about six to eight hours every day. Then, I did three hours of outreach per day, teaching kids about science, technology, engineering and math. Then I did about two to three hours of interviews with local media per day. So, yeah, I worked. I was busy.
What did you do for entertainment? Was there a TV in the module?
There was a TV down there, but I never turned it on. For 100 days I never turned the TV on. I was literally too busy. I’m not a guy that really needs entertainment. For fun I read journal articles. I’m a pretty boring guy (laughs).
What did your research show from your time underwater?
We decreased all the inflammatory markers in my body. We wound up doubling our sleep in depth and breadth. We wound up decreasing our cortisone, which had a corresponding increase in testosterone. I’m talking about blood results. These are the initial preliminary results that we have gotten. I haven’t gotten all the full results back. I’m still crunching data points, but initially an increase of coherence in your brain, a decrease in phase lag, so that means your information is traveling faster. Lots of great stuff came out of this that we pretty much knew would happen, but we were hoping.
How did you figure that hyperbaric pressure could help people in many ways?
I’m an assistant professor of medicine at Morsani medical college so I know a little bit about physiology and I know a lot about hyperbarics, and from reading the papers and doing all the teaching I know that this kind of stuff does things like increase telomere length (thought to result in longer life), increases the number of stem cells. So I said to myself, overall, this could be an anti-aging type of a drug.
You’ve stated that hyperbaric pressure and increased oxygen help alleviate many conditions, from brain injuries to burns. How does that work?
With the burn injuries, it’s pretty easy and straightforward. We understand that oxygen in and of itself is a vasoconstrictor
. That means it makes your veins and arteries smaller. As it does that, it actually decreases inflammation. The other thing that it does is it releases stem cells in your body, and these are all the mechanisms of hyperbaric medicine. If you apply these mechanisms of action, they don’t only do it when you have burns. It always vasoconstricts, which always reduces edema in any situation. So if we have a disease that has edema, we can go, oh, yeah, we can reduce that edema. Same thing with stem cell production. So you’re healing quicker because you’re making more of those stem cells.
You reported that one consequence of this experiment is that you were no longer 6 ft. 1 inch tall when you surfaced.
I’m now 6 ft. and a quarter-inch. It’s kind of hard, but I’m okay with it.
Did it compress the discs between the vertebrae, as happens to a number of people on land over time? Will you eventually return to 6 ft. 1?
That’s the question. I’m currently hanging upside down. But we knew this going in. We supposed it going in. Astronauts, they expand ... They grow about an inch and a half. Aquanauts are in compression, so they shrink. So hanging upside down on my upside down hanger thing, I’m trying to get back that three-quarters of an inch. Hasn’t worked just yet, but we’ll let you know.
Monitors showed that the pressure improved sleep. Were you able to feel the difference?
All I have is the anecdotal proof that I felt better. That doesn’t mean anything. Science wins over BS every time, right? So when I looked at the data, and the data said that I was sleeping between 60 and 66 percent in deep and REM sleep. That is unheard of…. Humans don’t do that. It’s crazy. We sleep so much better.
Food was brought to you from the surface. What was the diet like?
I would eat just a lot of salmon, and I ate exactly how I eat on the surface. I had three eggs in the morning. Normally I would fry them up in a frying pan. No frying pan down there. A small microwave. I basically learned how to cook eggs in the microwave without burning them…. For lunch I would have a salad with some protein in it, usually like some frozen chicken strips that I could heat up that were already precooked. And dinner would be, sometimes I’d have meat. They’d cook a steak and bring it down to me. I cooked salmon in the microwave and I’d eat that with some green thing, anything green.
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USF associate professor Joseph Dituri will speak about his experience and research living underwater for a record 100 days in a lecture at Harbor Hall on the USF St. Petersburg campus on October 11th.Did you have any problems down there?
One of the problems I had underwater was I cracked my tooth. 12 days into it I cracked a tooth. I'm talking with my doctors, and they’re all like, uh-oh, not sure what we can do for this one. So they called the dentist. It’s me grinding my teeth. I grind my teeth. So the long and short of it, we had to just tough it up, just tough it up and do your mission. The whole mission lasted 100 days and on day 12 I cracked my tooth. Oh, it hurt so bad.
Are you going to be talking about your experience during those 100 days in the lecture?
Yes, it’s going to have some stuff about the 100-day mission, but it’s (also) going to be talking about the greatest library on earth and why we need to save it. …
The greatest library on earth (is) 4.5 billion years of genomic wisdom. There are about 20 million species on this planet, and that biodiversity is the greatest library on earth. It’s the cure to all our diseases. It’s the cure to insanity. It’s the cure to cancer. All of that is contained in that planetary biodiversity, so every one of those creatures has a separate story and every one of the stories is stacked up in the library of human history. And this is the science that we need to talk about and make that science cool, so that somebody’s going to go, hey, we need to solve that planetary biodiversity thing.
For more information, go to Dr Deep Sea.