Imagine jumping in a pick-up game of basketball with some neighborhood friends, playing as hard as ever. It's summer, and the weather is hot and humid.
Thirty minutes later, you're exhausted. You look around for a bottle of water and realize you forgot to bring one. In fact, you haven't had anything to drink for hours.
Your heart's racing, you're sweating more than usual and feeling slightly dizzy. You also feel nauseous.
It's possible you have heat exhaustion.
Heat exhaustion occurs during prolonged exposure to high temperatures, and often leads to excessive sweating and dehydration. It's one of several conditions that fall under the broader umbrella of heat-related illnesses, the most serious of which is heat stroke [source: UMMC].
Though not inherently deadly, heat exhaustion's ability to escalate is the primary reason to take the condition seriously.
So what happens to the human body during heat exhaustion?
When a person is exposed to higher-than-normal temperatures, his or her body will sweat as a cooling mechanism. But if a person sweats too much without replacing the water and vital nutrients, dehydration kicks in and the body can't keep up with its rising temperature. This is doubly dangerous in humid weather, where sweat evaporates slower, delaying cooling off of the body [source: CDC]. When the body can no longer control its temperature, the effects of heat exhaustion kick in [source: UMMC].
As we've pointed out, keeping heat exhaustion in check is essential in preventing heat stroke.
In this article, we'll look at five supplements that assist the human body in both warding off and recuperating from heat exhaustion.
But first an important note: Water, water, water. Though not a supplement on this list, water is the most important thing a person should consume when overheated. Drinking cool water both replaces that lost to sweating and assists in bringing down your core body temperature. Just make sure it's not too cold to avoid stomach cramps [source: CDC].
Argh, matey! Where'd you put the barrel of oranges?
Many of us learned in history class how vitamin C prevents scurvy, a now-rare condition once dangerous to sailors. Today, the vitamin is mostly associated with boosting the immune system or in fighting the common cold [source: MedlinePlus].
One of the most common supplements found on store shelves, vitamin C is taken for a variety of purposes. In addition to helping the immune system, vitamin C has been known to aid in the prevention of heat exhaustion.
In one case, employees of a sweltering factory reported fewer incidents of heat exhaustion when given ascorbic acid (vitamin C) before work. Over a nine-year period, no incidents of heat exhaustion were reported where they had been in the past [source: Weaver].
And in other cases, vitamin C has been shown to help patients better acclimate to hot and humid temperatures when taken over time [source: Ringsdorff]. That means those who consume enough, through a supplement or from fresh citrus fruits and juices, can better withstand weather that leads to heat exhaustion.
For our next supplement, the good news is you could be getting plenty with your morning cereal.
You were always told to drink your milk as a kid, right? Next up is a mineral necessary for healthy bones and muscles: calcium.
It's is one of the essential minerals lost when the body enters a state of heat exhaustion, or worse, heat stroke. Calcium also happens to be the most abundant mineral in the human body [source: UMMC].
Despite its abundance, calcium needs to be replaced to ensure the health of cells, especially in people spending a lot of time in hot conditions. Cells use calcium as a means of storing potential energy, which in turn is used to power a number of things, namely the contraction of muscles [source: URMC].
To make things worse, when heat exhaustion becomes heat stroke, patients can experience a condition called rhabdomyolysis, where muscles begin to break down and damage the kidneys [source: Sprung]. This in turn causes an increased calcium deficiency called hypocalcemia, creating a downward spiral.
The good news is that calcium is readily found in sources like dairy products and green, leafy vegetables. It can also be taken in calcium carbonate supplements, the same found in many antacids.
Let's move on to No. 3 in the list, a trace mineral that does a lot of good in restoring those with heat exhaustion.
The next supplement for heat exhaustion, magnesium, may be a trace metal, but it bears major importance to human health.
Like calcium, magnesium is abundant in the human body (fourth-most common mineral, to be exact). It is necessary for more than 300 biochemical reactions and is responsible for strong bones, a healthy nervous system and functioning heart [source: ODS].
This last one is of note, because heat exhaustion bears particular strain on the cardiovascular system, especially in people who already have high blood pressure [source: CDC].
Along with calcium and our next two supplements, magnesium is an important electrolyte lost during dehydration.
Because plants need magnesium for chlorophyll, it's readily found in leafy green vegetables, many legumes and whole grains. For those looking to take a supplement, the mineral comes as magnesium sulfate, magnesium carbonate and magnesium oxide [source: ODS].
What do broccoli and bananas have in common? To find out, let's look at our next supplement in warding off heat exhaustion.
If you've ever had a sports drink after exercising, you may have wondered what's in the stuff that's supposed to be good for you. Monopotassium phosphate? Is that just a preservative? Hardly.
The second-most important supplement on our list is potassium, another mineral that serves a necessary purpose in the human body. Potassium, along with calcium and magnesium, works as an electrolyte to carry electrical impulses across cells.
But this isn't just any electrolyte. Potassium plays an important part in the transfer of ions through cellular membranes in a process called the sodium-potassium pump. The sodium-potassium pump does a number of things, including the important task of transmitting nerve signals [source: Goodsell].
Potassium is found in a number of foods, including all meat sources and soy products, broccoli, lima beans, potatoes, citrus fruits and of course, bananas [source: MedLine Plus]. There are also plenty of over-the-counter supplements.
But since we're talking heat exhaustion, and we've established the need to replace lost water due to dehydration, sports drinks are a great option. Most all of them have monopotassium phosphate or some other source of potassium to replace the lost electrolyte.
Let's move on to the final supplement on our list, one necessary for many functions in the body.
Our final supplement -- the most important thing a human body needs next to water when facing heat exhaustion -- is sodium.
Depending on what you've heard, sodium gets a pretty bad wrap. And it's true that doctors suggest many Americans already consume an excess of sodium, much of which comes from processed foods. But sodium, specifically sodium chloride (table salt), is the No. 1 electrolyte that needs replacing when we sweat.
For someone experiencing heat exhaustion, excessive sweating is a common symptom. The body is trying to rapidly cool itself and will shed salt and water to do so. But even if you're drinking fluids, you can still succumb to heat exhaustion if they don't have enough salt in them [source: UMMC].
And as you may have guessed, sodium is the other important part of the equation in the sodium-potassium pump. See, molecular biology isn't that hard.
Like potassium, sodium is a soluble electrolyte added to sports drinks for rehydration [source: CDC]. These kinds of drinks are the quickest way to get both water and the aforementioned electrolytes back into your body.
Remember that a healthy diet including the daily recommended allowance of vitamin C, calcium, magnesium, potassium and sodium is the best way to stay fit when facing hot and humid weather.
And if you even think you're going to run into friends asking you to play a little roundball, make sure to grab your water bottle next time.
Regularly popping a fish oil supplement was once considered beneficial for cardiovascular health. A big 2018 meta-study challenges that assumption.
- Centers for Disease Control. "Extreme Heat: A Prevention Guide to Promote Your Personal Health and Safety." July 31, 2009. (May 9, 2012) http://www.bt.cdc.gov/disasters/extremeheat/heat_guide.asp
- Goodsell, David. "Sodium-Potassium Pump." RCSB Protein Data Bank. October 2009. (May 12, 2012) http://www.rcsb.org/pdb/101/motm.do?momID=118
- MedLine Plus, U.S. National Library of Medicine, National Institutes of Health. "Electrolytes." Sept. 20, 2011. (May 12, 2012) http://www.nlm.nih.gov/medlineplus/ency/article/002350.htm
- MedLine Plus, U.S. National Library of Medicine, National Institutes of Health. "Potassium in diet." May 25, 2010. (May 12, 2012) http://www.nlm.nih.gov/medlineplus/ency/article/002413.htm
- MedLine Plus, U.S. National Library of Medicine, National Institutes of Health. "Vitamin C." March 14, 2012. (May 10, 2012) http://www.nlm.nih.gov/medlineplus/druginfo/natural/1001.html
- Office of Dietary Supplements, National Institutes of Health. "Magnesium." July 13, 2009. (May 12, 2012) http://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
- Ringsdorff, W.R. and E. Cheraskin. "Vitamin C and tolerance of heat and cold: human evidence." Orthomolecular Psychiatry. Vol. 11, no. 2. Pages 128-131. 1982. (May 10, 2012) http://orthomolecular.org/library/jom/1982/pdf/1982-v11n02-p128.pdf
- Sawka, Michael N. and Scott J. Montain. "Fluid and electrolyte supplementation for exercise heat stress." The American Journal of Clinical Nutrition. Vol. 72, no. 2. Pages 564-572. August 2000. (May 9, 2012) http://www.ajcn.org/content/72/2/564S.full
- Sprung, Charles L., Carlos J. Portocarrero, Antoine V. Fernaine, and Peter F. Weinberg. "The metabolic and respiratory alterations of heat stroke." Archives of Internal Medicine. Vol. 140, no. 5. Pages 665-669. 1980. (May 10, 2012) http://archinte.jamanetwork.com/article.aspx?volume=140&issue=5&page=665
- University of Maryland Medical Center. "Calcium." 2011. (May 12, 2012) http://www.umm.edu/altmed/articles/calcium-000290.htm
- University of Maryland Medical Center. "Heat Exhaustion." 2011. (May 9, 2012) http://www.umm.edu/altmed/articles/heat-exhaustion-000075.htm
- University of Rochester Medical Center. "Rare genetic syndrome may hold key to cure for heat stroke." April 8, 2008. (May 12, 2012) http://www.urmc.rochester.edu/news/story/index.cfm?id=1949
- University of Wisconsin-Madison. "Ions in solutions (electrolytes)." 2010. (May 15, 2012) http://chemed.chem.wisc.edu/chempaths/GenChem-Textbook/Ions-in-Solution-Electrolytes-598.html
- Weaver, W.L. "The prevention of heat prostration by use of vitamin C." Southern Medical Journal. Vol. 51, No. 5, Pages 479-481. May 1948. (May 10, 2012). www.seanet.com/~alexs/ascorbate/194x/weaver-wl_southern_med_j-1948-v41-n5-p479.htm