We’ve all heard of electrolytes, especially since sports drinks tend to market themselves as “scientific” and throw around “scientific” words to make themselves sound more impressive. In reality, electrolytes are substances that become ions in the blood stream and the balance of electrolytes in our system is essential for the function of cells and organs. They are used to conduct electricity and carry electrical impulses such as nerve impulses and muscle contractions. The kidneys work to keep electrolyte levels in your blood constant. You lose electrolytes through sweat, which is why sports drinks emphasise that they replace electrolytes. Let’s take a look at some of the electrolytes in your body before we take a look at some sports drinks and what they actually contain.
The major electrolytes in your body are:
– Sodium (Na+)
– Chloride (Cl-)
– Potassium (K+)
– Calcium (Ca2+)
– Magnesium (Mg2+)
– Phosphate (PO42-)
– Bicarbonate (HCO3-)
– Sulfate (SO42-)
Sodium is one of the major positive ion (cation) in fluid outside of cells. Many of you are probably familiar with sodium chloride, which is the scientific name for table salt. Sodium regulates the water levels in the body, which is why those trying to lose weight should avoid salt as much as possible as it causes water retention (excess salt is a big dietary problem; salt deficiency is very uncommon). The brain, nervous system and muscles require electrical signals to communicate, thus a good sodium level is critical for proper function.
An increase in sodium, known as hypernatremia, occurs when there is excess sodium in relation to water (which is why everyone recommends drinking more water). By contrast, a decrease in sodium level is known as hyponatremia. The normal blood sodium level is 135 – 145 mmol/L (millimoles / Litre).
This is another major cation found in cells. It helps regulate heartbeat and muscle function. Abnormal changes in potassium levels can impact on the nervous system and cause irregular heartbeats (arrhythmias), which can be fatal.
An increase in potassium levels is known as hyperkalemia and a decrease is known as hypokalemia. Potassium is normally excreted by the kidneys, so diseases that affect the kidneys can cause either one of these. The normal blood potassium level is 3.5 – 5.0 mmol/L.
This is the major negatively charged ion (anion) found in the fluid outside of cells and in the blood. Sea water has almost the same concentration of chloride ions as human body fluids. An increase in chloride levels is known as hyperchloremia while a decrease is known as hypochloremia. The normal range for chloride is 98 – 108 mmol/L
This ion acts as a buffer to maintain the pH level in blood and other bodily fluid. It acts to regulate acidity levels in the body and the normal range is 22 – 30 mmol/L.
Powerade and Conclusion:
I have a bottle of this with me right now, so let’s take a look at the ingredients. All sports drinks are roughly the same so I’ll just focus on Powerade since I have the bottle with me and since its nutritional table is more helpful than the Gatorade one. In terms of the electrolyte content, per serving there is 7.2mmol of sodium and 2.4mmol of potassium (where a serving size is 600mL). The ingredients list sodium chloride, which we all know is just salt, and to cover up the salty taste it lists sucrose, which is basically table sugar. Sucrose is a simple carbohydrate; I’ll leave it at that for now. The drink also contains high fructose corn syrup and sucrose syrup.
Essentially, the two drinks are meant to help maintain electrolyte and carbohydrate balance through salt and sugar. That’s also the problem. If you’ve heard anything about the state of the Western diet and its health problems, you’ll know that salt and sugar are the two worst things happening to people right now. This is compounded by the fact that to restore carbohydrates, these drinks use simple carbs.
Now if we keep in mind that this is sports drink, it’s not necessarily a bad thing. Athletes are less likely to have an excess of sodium chloride in their diets (as opposed to the rest of the world) and a quick hit of carbs during exercise can help prevent catabolism and facilitate refuelling. The only concern I would have in this regard is that despite marketing itself as an electrolyte replenisher, sports drinks only contain two of the most common electrolytes because they’re just using common salt.
The problem is that the drink is available to anybody. It sits in the drink section as if it were just another drink. A lot of drinks have sugar in it already, but sports drink also have salt, making things worse. The contents include sucrose syrup (liquefied table sugar) which is high in empty calories. Powerade actually has less sugar in it than Gatorade, but let’s take a look at Gatorade (because I have the numbers from a study here). Gatorade contains 14g of sugar per 100g, which is equivalent to about 3.3 teaspoons of sugar. The entire bottle (which is one serving) will give you 8 teaspoons of sugar. Additionally, the high fructose corn syrup content has been shown to significantly and independently increase risk of hypertension in people with no previous history of the disease (American Society of Nephrology, 2009). Imagine a regular person adding all this to their diet because they perceive the sports drink as being healthier than the soft drink.
In fact, even if you are an athlete and regularly exercise, I still would not recommend sports drinks at any time other than when you are actually in the middle of exercising. This is the only time where a sugar and salt hit will not necessarily be bad for you, but the other ingredients still make the benefits of the drink questionable. All in all, I would still go for just water and maybe a quick, bite sized snack like fruit or nuts. Personally, I carry a bag of almonds around and just pop a few in my mouth while I’m at the gym. The protein and calorie content of almonds are amazing for building muscle.