Virtually all non-US carriers which I can recall recently have such signage. I know that William also flies non-US carriers.

Ridiculously inaccurate paraphrase. Quote anyone advising "not to stay hydrated". I know I just said that doing somersaults out of a desperate fear of being dehydrated was obsessive. I'm all in favor of taking water on, but I'm also in favor of a practical solution of which there are several. Trouble is when someone is adither about "not being hydrated", they discard every practical suggestion. That's what extreme anxiety does to the mind.

It isn't very difficult to find the posts from mileena about their health issues, if you are not familiar with them. Even then, it isn't just those who have health issues who are subject to DVT, as noted earlier in this thread.

I see only one other post supporting mileena regarding not staying hydrated on an aircraft. This isn't about being 'obsessive' about hydration, or 'extreme anxiety'. It is about basic, common sense when it comes to in flight health.

I don't read that as advising not to be hydrated. It is literally a QUESTION why you want to be hydrated. The reason for the question are given. Was the answer given.

Explain how that is. I know they advise liquids for the sick. But for the healthy? Those of us who are healthy never get sick from failure to drink lots of liquids. Its like food. The body knows what it needs. You don't have to force it. Show my anything from a professional source that warns of any DANGER of sickness by drinking the way the normal majority does, without any conscious intent.

Don't know the humidity of a plane, but I do know from enough trials that I can take any trip up to about 8,000 miles without spending any time focused on "hydration" and not get sick. Maybe this is more about hypochondria.

Yes, you are correct. Healthy people should drink... when they are thirsty. Not the biggest deal. People with sicknesses of many sorts may need to regulate their water intake higher or lower; many conditions can give this need for tighter regulation.

In the past there was a persistent "saying" that people "needed" 8 glasses of water a day. That was pretty much a myth too.

http://www.cbc.ca/news/story/2003/03...ses030314.html

It hasn't been taught anymore by physicians.

That being said I would recommend drinking a bit of water when traveling on a dry plane for comfort... that's why they generally serve water right away (pretty soon we'll have to pay for that too). ;) Humidity is *extremely* low on a plane.

I can't provide professional sources, but I can provide a 100% trustable anecdote. (hey, it's the internet, you get what you pay for)

I know someone who used to drink water when they felt thirsty. Over a 4-5 year period, this person suffered from no fewer than 4 bladder infections, 3 of which required visits to the emergency room. Since then (10+ years), they have made an effort to drink more water than the minimum necessary to feel well, and not a single infection.

This doesn't necessarily mean this person needs special treatment - a day with low water intake will probably not hurt - but let's not paint everyone with the same brush.

Again, how often do you actually fly? and how often do you fly long haul? There is a noticeable difference in how the body reacts in terms of jet lag for instance when one stays hydrated whilst in flight.

I certainly notice a marked difference when I don't drink enough while travelling, and I am certainly no hypochondriac, nor do I follow some sort of 'fashion' such as may be common in America to always carry a water bottle.

Again, many of us who actually fly very regularly, and especially long haul, have realised the benefits of drinking more in flight than we would do on a normal non-travel day.

I concur. I flew LHR-NRT-KUL-SIN-LHR in a comparatively short space of time last year and noticed myself feeling markedly worse on and after the last segment, when I did not have the opportunity to bring water on board. The Singapore Girls were very nice about bringing around water and juice, but as I was in whY I didn't feel comfortable asking more than about once an hour.

That is correct about 95% of the time. Also saw the signs onboard Delta by the way.

I agree with most of your posts, LuvAirFrance, but not this time.

"It's like food. The body knows what it needs". Well, not really, or we might not have a fast food epidemic in this country.

I spend a lot of time thinking about hydration - a penchant for endurance sports, back country and desert living can have that effect.

There are many reasons folks get dehydrated. They make the mistake of assuming thirst = first sign of dehydration. Wrong. Dehydration is already setting in by the time you feel thirsty. They haven't learned to compensate for the dry air sucking the moisture out of their bodies. They deliberately underhydrate because they don't want to deal with toilet issues.

It's not a 'one-size-fits-all' issue. Different folks are going to need different amounts of hydration to stay healthy, no surprise there. Further, much of what is called 'jet-lag' is undoubtedly partly the results of poor hydration.


Slightly OT. I was a chronic 'under-hydrator'. Got into endurance sports a few years back, mostly in desert areas. I learned to drink two and three times what felt 'normal'. I also learned that an under-hydrated body and mind might seem 'fine', but only until compared to a well-hydrated body's performance.

For me personally, if I am in 'office' mode, I drink 1-1/2 liters of water during an eight hour day. I used to take that much water on any longhaul flight, and because airplanes are so much drier than my workspace, that was barely adequate.

A few weeks ago in Switzerland I noticed that my skin was so dry it was actually puckered. It wasn't from heat (it wasn't that warm) but I suspect from a lot of long haul flying over a two week period without always having enough water at hand.

And how many of us having awoken in the wee hours of the morning, dying of thirst, and raided the hotel mini bar? I tend to drink more for at least a day after a long haul flight because my body demands it. And as chollie points out, by the time one feels that demand one is already dehydrated.

Same here.For sure.

Bruce

Yep, a subset of people need close monitoring of fluid status, but most people are fine and really resilient. The average person really doesn't need to worry unless they want to worry about such things. :p

Probably the best 'rule of thumb' for an average person is that you should keep your pee quite clear. If it is turning strongly yellow even routinely you might want to increase fluid intake (coffee / alcohol does not count as these are also diuretics...) Of course, special considerations take precedence.

Back in residency a few of us did experiments on ourselves regarding dehydration at the end of a long shift, and saw how concentrated we could get our blood as measured by salt concentration. It was quite impressive...

You brought up another good point. The ONLY time my medical professional mention hydration is when I'm sick. Even when my doctor knew I'd flown from the midwest to Bulgaria, he said nothing. But I got a virus in Bulgaria. I had diarrhea. Even that doctor didn't ask "are you hydrating?" Truth was that I was drinking LOTS of bottled water since my stomach was refusing pretty much everything else. I wasn't trying to hyrdrate, just avoid regurgitation.

I think its all this "alternative medicine" around these days looking for easy answers to complicated problems: colon cleansing, detoxifying, hydration. They basically contend that conventional medicine is promoting ill health. I guess if you buy that whole line, you might start fearing dehydration. But for most of my life, my health has been above average. So I have to reason to search in eccentric sources for an "answer"..

Yep. You seem to be quite reasoned / sophisticated in your understanding :). There are a lot of nuances -- there is a big difference between systemic volume loss and surface drying of membranes -- really what would be the best thing to have flyers "feel better" would be humidity in the cabin, which the 787 is supposedly much better with higher humidity. The cracking and drying of your nasal membranes can possibly lower your barriers to infection and make you more vulnerable to being sick... Taking a few sips of water (again that's why they serve it) may help with your throat moisture, and clearly on the extremes it is not good to be really, really dry during the flight. I personally avoid alcohol on all flights for that reason -- it makes me feel pretty lousy due to its systemic and surface drying effects, definitely not what you want to do if you plan on staying "hydrated" but very common, and hey, the vast majority of people do absolutely fine with this. If you want to have a beer on the plane and are healthy, go right ahead.

Those people that drink huge amounts of water on the plane are likely driven by the dry feeling of their throat etc, not actually fluid loss (if you are still peeing a lot, you weren't actually that depleted... ;) Water can indeed help a bit with this, and if it makes you feel better go right ahead.

Those prone to venous blood clots and other conditions should probably drink a bit more fluid, but moving around during long flights is equally, if not more important.

Many armchair docs around spreading a lot of questionable advice (one person told me once, "by the time you are thirsty, it is already too late!!!") Too late for what? Water is necessary, but the hysteria regarding all of this is a bit overkill IMO.

Anyways, I won't really post on this topic more, as people tend to just believe what they want to believe.... just have a nice discussion with your own doc if you are concerned about any particular conditions you might have. If you are healthy, otherwise just have a bit of water when they serve it and you will be fine.