Jun 2015

Post Dive Drinking and Dehydration

By Mike Waddington

It is no secret that many divers love a drink. What can be more refreshing than cracking open an ice cold beer after spending a day bathing in the sun’s rays and scuba diving. Many dive resorts have bars attached where it is common to see customers and dive staff drink the night away before waking up early for another day of diving. Although after a days diving that nice cold beer might seem like just the thing you need, it is actually one of the last things you should consider putting into your body.

Even after we surface from a dive, our body’s need to work hard to eliminate the excess nitrogen in the blood stream. Drinking alcohol immediately after a dive is not advised because alcohol may affect the way that our body eliminates that excess nitrogen. Dehydration is one of the main factors involved in decompression sickness (DCS), and drinking alcohol is one of the most efficient ways to thoroughly dehydrate ourselves. When we become dehydrated the volume of blood in circulation lowers, however we still keep the same amount of dissolved nitrogen in the blood stream. By drinking alcohol after a dive it is possible to dehydrate ourselves to a point where we get DCS (although this is still very rare). Drinking lightly after a dive can lead to dehydration, but drinking heavily after a dive is far worse. The effects of alcohol can even mask the symptoms of decompression sickness, which can often lead to a serious delay in treatment.

After a dive it is not the beer that we should be reaching for, we need to rehydrate ourselves. The powerful sun and humid air in tropical dive destinations can lead to dehydration before a diver even gets on the boat to go diving. The same applies for divers in colder waters. It is common that divers spend a lot of time on boats or on the shore wearing thick exposures suits, but still being exposed to the sun. Diving itself is also dehydrating. Although we may not feel it, our body still sweats underwater, and we lose water when we breathe the dry air from scuba cylinders.

Diving is very popular in resort areas, where drinking is also usually very popular. Many divers choose to take diving holidays, where they go to a nice (usually tropical) location, and complete as many dives as they can in a week or two, often completing two or three dives in a day. These are the divers who are at most risk, as they get up early, not drink any or enough water and complete two dives. Following a lunch break they may jump on another boat and go diving again, or maybe hit the bar and start tasting all the different cocktails on offer. Many divers find themselves living in a state of constant dehydration, which is not only extremely dangerous, it also leads to extreme fatigue and painful headaches. This should be the last thing anyone wants while on holiday!

It is also important to mention that alcohol is not the only beverage that divers drink heavily that leads to dehydration. Caffeine containing drinks can also lead to dehydration, but not nearly as much as alcohol. Drinking a cup of coffee or a can of Coke wont in anyway help rehydrate you. Fruit juices are good but the acidity may cause some divers to suffer from Pressure Triggered Gastoesophageal Reflux Disease” or “GERD” for short. Coconut water is one of the best ways to quickly rehydrate, plus it is good for you, and tastes delicious! Isotonic drinks such as Gatorade or Powerade are ok, but they are designed to replace electrolytes lost through sweat, not to replenish water levels.

Drinking plenty of water is of course the best answer. Drinking water before immediately before and after a dive will help rehydrate a diver’s body, however the body can only absorb so much water at a time. So for those of you that chug two pints of water after a heavy drinking session, I’m afraid to tell you that the only thing you’re doing is making it more likely you wet the bed.

Do yourself a favour and wait a few hours at least after a dive before starting on the booze. If you are planning to dive early the next day try to not drink anything the night before, as you probably won’t be able to rehydrate sufficiently before the morning. If you drink a little too much then you should cancel the early morning dives. Being hungover is a clear sign that your body is extremely dehydrated. When hung over, divers tend to have less focus, which leads to pre dive safety checks being rushed or omitted altogether so the diver can rush into the water to cool their head off. Hangovers not only predispose divers to decompression sickness, but also may lead to impaired judgement and coordination. I am not telling divers that they shouldn’t drink, but scuba diving and drinking alcohol just doesn’t mix. Everyone likes to let go every now and then, but if you do then you should be a responsible diver and not dive until you have recovered properly.

‘Post Dive Drinking and Dehydration’ was written by Mike

Get the latest deals straight to your inbox.

Mike Waddington

I first discovered diving in 2008 after going snorkeling on the Great Barrier Reef in Australia. After trying diving at a flooded quarry in England I decided to head out to warmer more interesting waters in Thailand where I ended on the Island of Koh Tao completing my Open Water course. Instantly addicted with money to spend and plenty of time on my hands I decided to continue until I became a Divemaster so I could live what seemed as the perfect life.

After that I headed to the Caribbean to an island called Utila to complete my instructor course, I spent several months out there completing the MSDT internship, teaching students and leading dives. This is also where I discovered my interest in the technical side of diving, taking part in equipment repair courses and learning about blending gasses and running compressors.

With all my new qualifications it was time to head back to where it had all started, Back to Koh Tao where I intended on living the dream. Once I arrived I quickly found a job and started teaching straight away. During my time on Koh Tao I took part in all many technical diving courses, learning how to dive with re-breathers, in caves and even going down to 90m/300ft!


PADI Master Scuba Diver Trainer
PADI/DSAT Tech Deep Instructor
PADI/DSAT Gas Trimix Gas Blender
PADI/DSAT Trimix Diver
TDI Intro to Cave Diver
TDI Advanced Wreck Diver
TDI Inspiration rebreather Decompression Procedures
PADI Professional Videographer
BSAC Compressor Operator
TDI Equipment Service Technician

Dream Dive Locations:

Silfra, Iceland
Cenotes, Mexico
Chuuk Lagoon, Micronesia
Ice Diving in Russia