You've probably seen those ads for sports drinks that claim to offer better hydration than water during or after an intense workout. The reason, they say, is that sports drinks replenish electrolytes; water does not.
Are these claims valid, or are sports drink companies just trying to sell you their products? What, exactly, are electrolytes? And is it really so important to replace them?
It turns out, there is some truth in advertising. According to Lynne Braun, PhD, CNP, a nurse practitioner with the Rush Heart Center for Women, electrolytes are a health essential.
The essence of electrolytes
You're probably familiar with most or all of the electrolytes, even if you didn't necessarily know they were electrolytes:
These electrically-charged minerals help regulate everything from hydration (the amount of water in your body), to your nervous system to muscle function — including the most important muscle of all: the heart.
Electrolytes enable the electrical impulses to be generated normally within the heart, so your heart can contract and relax at a normal rate.
"The heart can't pump without electrolytes. If you think of the heart as a lamp, electrolytes are like the electrical circuit, generating the current that keeps the light burning steady and strong," Braun says. "If the connection is weak or disorganized, the light might flicker rapidly or dim — it won't work properly. If you unplug the lamp, it won't work at all."
Out of synch
Similarly, your body can't function without electrolytes. And if the level of one or more electrolytes becomes too low or too high, it creates an imbalance that can cause everything from mild, temporary symptoms to serious long-term health problems.
Exactly how the imbalance affects your health — and how quickly symptoms appear — depends on which electrolytes are affected, and how high or low the levels are.
For instance, over time, calcium deficiency will weaken bones and, possibly, cause osteoporosis. Very high calcium, on the other hand, can lead to kidney failure, abnormal heart rhythm (arrhythmia), mental confusion and even coma.
Arrhythmias can also result from low magnesium, as well as high or low potassium levels, especially in people who already have a heart condition.
When to worry?
The good news: Most of the time, healthy people don't have to worry about electrolytes. "If you're getting enough electrolytes through your diet and staying properly hydrated," Braun says, "your levels should be OK."
So when should you be concerned? These are some common causes of electrolyte spikes or dips:
- Taking diuretics
- Prolonged vomiting, diarrhea or high fever, such as from a virus
- Congestive heart failure
- Hormonal or endocrine disorders, such as primary hyperparathyroidism
- Certain cancers, including breast cancer, lung cancer and multiple myeloma
- Eating disorders
- Drinking too much water, which can cause overhydration
- Kidney disease
The key to preventing health-threatening imbalances is to be aware of these instances when electrolytes are more likely to become depleted or build up. And, if need be, get advice from your doctor or another health care provider on how to maintain or restore the balance.
While some situations, such as health conditions, are beyond your control, Braun says there are steps you can take to avoid severe electrolyte spikes or dips:
1. Eat your electrolytes.
Make these electrolyte-rich foods part of your daily diet:
- Calcium – Milk and milk products (including plain, nonfat yogurt), meat, fish with bones (e.g., sardines), eggs, fortified breakfast cereals, beans, certain fruits and vegetables (e.g., asparagus, collard greens, dried apricots and figs)
- Chloride – Olives, seaweed, rye, tomatoes, lettuce and celery
- Magnesium – Leafy green vegetables (e.g., spinach, turnip greens, collard greens, kale), whole grains, nuts, peanut butter, dried beans and lentils
- Potassium – Cooked spinach, sweet potato, plain nonfat yogurt, bananas, avocado, peas, beans, tomatoes, oranges, melons, prunes and raisins
2. Go easy on the salt.
Although sodium is a vital electrolyte, your body doesn't need a lot — just 1 teaspoon daily. Too much salt can contribute to high blood pressure and other health problems. Try these salt-saving tips:
- Use fresh herbs and spices, or citrus juice to season your food.
- Avoid pre-packaged meals, which tend to be very high in sodium.
- Choose "reduced sodium" canned soups and vegetables. Always read the labels!
- Taste your food first. Don't automatically reach for the salt shaker; you might find your food doesn't need it.
3. Drink enough water.
You may feel like you hear this too often. But it's good advice. Don't wait until you become dehydrated to drink fluids; keep a water bottle with you and drink small amounts throughout the day.
Even if you don't sweat a lot, you lose electrolytes when you breathe rapidly. So sweaty or not, opt for a drink with electrolytes after any vigorous workout.
4. Replenish electrolytes after exercise.
If you do a long or heavy workout, it's important to replace the potassium, magnesium and/or sodium that can be depleted.
That's why Braun recommends replacing 8 ounces of your daily water with a sugar-free or low-sugar sports drink (e.g., Powerade Zero, 0g sugar, Powerade ION4, 3.9g sugar; Gatorade GSeries Fit 02 Perform, 2g sugar), or oral rehydration product (e.g., CeraSport, Drip Drop Hydration Powder).
"Even if you don't sweat a lot, you lose electrolytes when you breathe rapidly," she explains. "So sweaty or not, opt for a drink with electrolytes after any vigorous workout."
5. Push the electrolytes when you're sick.
When you're vomiting, have diarrhea or are feverish, you rapidly lose fluids and electrolytes, Braun cautions. Children and seniors, especially, can get severely dehydrated very fast.
Oral rehydration solutions like Pedialyte — which contain the right mix of salt, sugar, potassium and other minerals — are a good way to replenish those vital fluids.