What's the problem with electrolyte imbalance and how do I mitigate it?

Question

In the past week I've seen two answers mentioning electrolytes; one about the grand canyon and one in an answer on a question that was actually about wildlife, but where other desert dangers were described as well.

In the context of outdoor sports, what are electrolytes, why do I need them and where do I get them from? The Wikipedia article describes that this includes most soluble salts, acids, and bases. So is it simply a matter of eating salted food to compensate for the salt lost by sweat (for example, eating salted nuts), or are the problem and solution more subtle than that?

This answer mentions Gatorade, which appears to be a brand for commercial sports-themed beverages. The sport drinks I've tried in the past I found very distasteful, moreso the ones in powdered form. Do I need those, really, or will other food do, too?

Answer 1

There are two types of water-based concerns while doing strenuous activity in the desert: dehydration and hyponatremia.

Dehydration occurs when your body is not getting enough water, and is the most common. Symptoms include irritability, headache, lack of energy, bright yellow/orange and infrequent urine. You lose water while you sweat, but in hot climates you don't necessarily notice since it evaporates so readily. Along with that water, you also lose electrolytes (salts and minerals) that your body needs. Lose too much of those, and drink too much water without replacing them, and you tip the balance in the direction of hyponatremia.

Hyponatremia (which the questions linked allude to) is a very serious condition on the other end of the scale that occurs when one drinks too much water without replacing the salts sweated out. It is affecting more and more people exerting themselves in hot climates due to our increasingly "sodium free!" diets.

Your body needs salt to function, and as you sweat, you lose that salt (and other nutrients) which water alone will not replace. Usually this isn't a big issue, and the salts get replaced with meals etc. But if you are sweating a lot and drinking anything (water or sports beverages) to excess, hyponatremia can set in.

Symptoms of hyponatremia include headache, nausia, irritibility, disorientation, dizzyness, vomiting, seaizures, coma and death. It is not to be taken lightly. Interestingly, some of these symptoms are the same as dehydration... but if you are experiencing the above while your urine is still clear and copious (likely because you have dutifully been pounding drinks down) it is probably hyponatremia.

Prevention:

• Regulate Water Intake : if your urine is clear and copious, chances are you are sufficiently hydrated. Ease back, even if you are thirsty.
• Eat Food. Salty food. Pretzels, nuts, trail mix, granola bars... anything you can find. The general advice among Grand Canyon guides is eat regularly throughout the day. If you do that, drinking plain, clear delicious water is fine. However, drinking only sports beverages and not eating is setting you up for trouble**

**Sidebar: Several sources suggest that sports beverages can actually increase risk of hyponatremia since their deliciously tasty tangy sweetness can cause one to drink more fluid than they would otherwise.

Advice from the doctor at the Grand Canyon clinic as reported in the Wilderness Medicine Institute regarding the issue:

Prevention is a matter of being sensible, which is so often the case. Drink lots, yes, but eat salty foods regularly while exercising in heat. "Relying on electrolyte replacement drinks alone," writes Dr. Myers, "is absolutely ill advised."

If a patient is approaching a hyponatremic state:

Dr. Myers warns, that giving oral electrolyte replacement drinks, such as Gatorade, alone might damage the patient. These drinks are so low in sodium and so high in water the dilutional imbalance may be increased.

As a final note, this is not to advocate NOT drinking water while hiking, since Dehydration is just as bad and far more common. Be smart. Drink what you need, but not more. Be aware of what you body is doing.

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Additional sources, all of which authoritatively conclude the sports beverages do not prevent the onset of hyponatremia. If you are drinking to much, it is too much, regardless of what you are drinking.

Consensus Statement of the 1st International Exercise-Associated Hyponatremia Consensus Development Conference, Cape Town, South Africa 2005:

Ingestion of electrolyte-containing sports drinks does not prevent the development of EAH in athletes who drink to excess.

Clinical Journal of Sports Medicine:

The total cups of water (p=.004), electrolyte/carbohydrate solution (p=.005) and total amount of fluid ingested (p<.001) were significantly higher in [Hyponatremic] compared to [Non Hyponatremic] runners and the degree of hyponatremia was related in a dose dependant manner.

Runner's World:

[Bob Murray, PhD and the longtime director of the Gatorade Sports Science Institute] acknowledges that neither Gatorade's new Endurance Formula nor the traditional Thirst Quencher will prevent hyponatremia if a runner consumes too much sports drink during a marathon. "We can't add more sodium because the research clearly shows that too much sodium actually impedes hydration," he says.

Rock and Roll Marathon page:

Even Gatorade, Poweraide and all Sports Drinks or IV NS will therefore increase free water and lower serum sodium

Tangentially related study in Schizophrenic Patients:

Conclusion: Substitution of electrolyte-containing beverages is not likely to prevent water intoxication.

Answer 2

Your blood and body need sodium, potassium and various other solutes in order to function (without the correct potassium levels, your heart will start to fail etc)

In a hot country, where you may sweat a lot, and top up your liquids by drinking water, you lose these solutes quite rapidly. The quantities you require are generally a lot higher than you might expect, and you need to top them up quickly if you have symptoms, so eating salts may not be fast enough.

A drink with added salts and electrolytes gets them into your body much faster, as they are already dissolved. Gatorade and other sporting drinks have a solute balance that is appropriate for this scenario, so are recommended.

Answer 3

Your body needs a certain amount of salt (electrolytes) to process water (and also for many other bodily functions). If you don't have enough electrolytes then your body's use of water is not optimal. A typical American diet gives you enough electrolytes so that you actually do not need to do anything special to make sure you are consuming enough. If you are eating a "normal" diet (steak, potatoes, vegetables, etc) then there is no need for you to supplement, at least for typical daily activities, and even if you are doing moderate sports. When I go backpacking in the mountains, I tend to not be concerned about electrolytes because the foods we eat out there are replenishing them in any case.

If you are engaged in more extreme physical activity, like hiking in the desert and sweating a lot in the sun, then you can supplement your water intake with additional electrolytes. But beware of typical sports drinks like Gatorade, which are not a good idea because, although they give you extra electrolytes, they also give you extra sugar which reduces the rate of water absorption. Instead of these you can choose some sports drinks that contain electrolytes without the extra sugars or other artificial ingredients, or you can simply add a sprinkle of sea salt or table salt to plain water.

I grew up in the desert southwest and for us when we went outdoors boating or other activites in the sun, we usually would take along some salted snacks (chips, etc) in addition to plain water or iced tea.

Answer 4

I'll weigh in on the Gatorade part. No, you don't need Gatorade, or any other drink with the right salts in it. However, you do need to replace the salts somehow.

I use Gatorade because it's convenient (I have to carry the water anyway), the amount of electrolytes I need to replace is well matched to the amount of water I need to replace so having them in your drink makes it easy and so you can't forget, it makes a warm drink on a hot day actually seem OK, and it adds a little taste that helps get you to drink it. I use Gatorade specifically instead of other sports drinks because I'm familiar with it and know how much to use and how it works for me. I expect most properly forumulated sports drinks would be fine. For me Gatorade works and it's widely available, so I don't feel like being a test pilot. Remember why Gatorade was developed in the first place.

The powder is something you can take into the desert and not have to worry about it spoiling. Mixed Gatorade does spoil after a day or so, so I only mix up what I need at the time for whatever hike I'm doing. I bring only mixed Gatorade on a hike. It doesn't spoil so fast you have to worry about that. While I'm in the desert, that's what I drink, even when I'm back in the car or camp. When it's hot out, replacing electrolytes along with water in the right proportions is a good safe thing to do with no downside I've found yet.

Yes, it does have some calories. First, I don't mix it full strength. 1/2 to 2/3 of what the directions say seems to be about right. If I remember right, it's only a few 100 calories per gallon as I mix it. That's really pretty little considering you can hike all day on two gallons. You're still spending more calories hiking than the gatorade provides. Don't worry about it. A little sugar when you're exerting yourself can even be useful. I find that I don't feel hungry much when it's hot. The little bit of sugar in the diluted Gatorade is enough to make me not want to bring food, which actually makes a few things simpler. I find I can hike pretty much all day with the only calory intake being from the diluted Gatorade, and I feel fine. I usually go hiking in the morning and don't eat anything until I get back in mid to late afternoon.

I know some people don't like Gatorade due to the taste. First, it's not about the taste, get over it. Second, there are various flavors. I don't like the original bug juice at all, but if that's all that's available I'll use it. I find the fruit punch flavor really not that bad at all. I wouldn't drink it just for the flavor, but it's good enough that it's a positive instead of a negative, and it helps (for me anyway) to drink warm liquid when it's hot.

I found out the hard way once that there is such a thing as reduced calorie Gatorade. I was having a hard time finding a tub of powder, and could only find these packets. I didn't pay attention enough in the store to notice it was reduced calorie. Even though it was the fruit punch flavor that I think isn't really bad at all for the normal stuff, this stuff was vile. Yecch. I had nothing else, so I ended up doing a 10 mile hike on a hot day and went thru a gallon of that stuff. I made myself drink it whenever I got thirsty, but as soon as I got back to the car I found a store that carried the normal stuff and I tossed out the low calorie packets. Yucc. I shudder again just thinking about that.

Answer 5

So-called "sports drinks" such as Gatorade are miracles of modern marketing, surpassed only by bottled water. They are expensive and contain large amounts of sugar.

If you're hiking long distances in high temperatures (say 40 C or 105 F), then you have a long list of hazards to worry about, one of which is getting low on electrolytes. Higher on the list would be dehydration, sunburn, and getting lost. I only do this kind of hiking once in a while, but when I do, I usually try to do as much of it as possible in predawn hours, and to protect against sunburn I bring a hat and wear a long-sleeve shirt and a pair of long pants. If you get in trouble in these conditions, it may be a good idea to find shade, rest until sunset, and then hike out in the evening when the sun and heat aren't life-threatening.

In conditions like these, some people tend to get muscle cramps, which may be a symptom of electrolyte imbalance. If you're prone to this, it may be a good idea to carry a couple of the little tiny salt packets they give away at restaurants, and maybe some salty food such as crackers.