It’s summertime in Texas and if you’re anything like me that means you’re breaking a sweat just walking to and from your car. As a health professional I’m always encouraging people to drink more water and during the summer drinking water and staying hydrated are even more important. Adequate water intake helps your body transport nutrients and get rid of waste, regulates body temperature, and promotes mental clarity. With the heat comes an increase in water loss and the risk of dehydration. Dehydration leads to decreased blood volume, decreased cardiac output, decreased sweat output (and subsequent increase in core temperature), and decreased lubrication of the joints and muscle (which increases risk of injury). What is the best choice to stay hydrated during the summer, especially when exercising in the heat? What about all those fancy waters in the grocery store?
As a reminder, you should aim to drink a minimum of ½ your body weight in ounces each day (if you weigh 150 pounds, that would be 75 ounces per day – again, that is just a minimum). You want to make sure you are adequately hydrated before beginning any exercise or activity. For activity lasting less than an hour, plain water will suffice. If you are a heavy sweater and/or are outdoors for an extended period of time (greater than 45 minutes), drinking an electrolyte beverage will help you stay hydrated. Gatorade and Powerade (and other sports drinks) contain the electrolytes needed for hydration. These drinks contain sodium and potassium - both nutrients that are lost in sweat. In addition to these sport beverages, there are new, functional waters on the market. Coconut water is one of those. It is marketed as a low-sodium and “natural” hydration beverage. Coconut water, with no added sugar, can be a good choice for those exercising inside or for a shorter duration; but it lacks the necessary amount of sodium – a mineral a lot of people lose in sweat – to help you rehydrate. Again, if you are a heavy sweater and/or are exercising for an extended period of time outdoors, a sodium-containing beverage is necessary. Do watch out for flavored coconut waters as they may contain as much sugar as a 12 oz. can of soda.
Alkaline water is another popular functional water. Alkaline water is any water that has a pH above 7. It contains the minerals calcium, phosphorus, and magnesium, among other nutrients. Its touted health benefits include preventing disease and removing toxins that build up in the body due to the processed Western diet. While these benefits have yet to be proven by scientific research, there are a few claims worth exploring. As mentioned previously, alkaline water contains calcium and phosphorus and may promote bone health. Calcium and phosphorus help keep our bones strong, but they also support other body functions. When levels fall below normal, our body will pull these minerals from the bone weakening the bones and eventually leading to osteoporosis. These alkaline waters can help keep calcium and phosphorus at the appropriate levels. You can also get an adequate amount of these nutrients from consuming leafy greens, dairy products, and nuts. The alkalinity may also buffer the acidic hydrogen ions that build up during intense exercise (think about that burning feeling in your legs during a sprint) and delay muscle fatigue. Eating fruits and vegetables also promotes an alkaline body environment and is a cheaper alternative to buying alkaline water. For those who already eat enough fruits and vegetables, you may not notice a significant difference when drinking alkaline water.
While the jury is still out on these functional waters, there appears to be no harm in consuming the beverages as part of a balanced, healthy diet. It is important to note that those with kidney problems should check with their doctor before consuming alkaline water as the minerals may build up in the body due to poor kidney clearance. If you’re not meeting that ½ an ounce of water per pound body weight, you should start there. Set a small goal to drink an extra bottle of water each day, and stay hydrated so that you can enjoy those long, summer days and nights.