Fructose-rich caffeinated soft drinks are widely popular across the world and certainly require no introduction. However, their role in causing diabetes and obesity has been widely argued and the latest study has just added to this growing list.
The researchers belonging to a University at New York has recently investigated how these soft drinks affect the human kidneys when consumed after a workout.
The findings of these studies can be found in the American Journal of Physiology—Regulatory, Integrative and Comparative Physiology.
The Association between Exercise, Heat and Kidneys
When you are working out in a hot environment, the blood flowing through the kidneys is reduced. This helps in the regulation of blood pressure and saves water. This is considered a normal response of the body and does not lead to any damage.
However, the same situation in a clinical scenario may lead to acute kidney disease (AKI) because of a decrease in the supply of oxygen to the tissues.
Earlier studies have established that doing exercise at high temperatures enhances the AKI biomarkers. Moreover, the research also suggests that consumption of a high-fructose drink further enhances this risk of AKI in the rat model.
As per the authors, the basic aim of this study was to check the validity of a hypothesis. The hypothesis stated that consumption of soft drinks after you have just finished working out in a heated environment increases the AKI biomarkers, as compared to the water control trial group.
It is a common practice for most of the people to consume soft drinks after exercise. In a similar manner, people involved in hard manual labor are also seen with this habit. Therefore, it is extremely important to realize why and how this behavior can be dangerous for kidneys.
To investigate further, the researchers took 12, healthy and physically fit adults of 24 years as an average age. The participants completed a running exercise for 30 minutes using a treadmill and then performed 15 more minutes of tasks at an agricultural site.
After 45 minutes of activity, the participants were allowed to relax for 15 minutes. The research team then provided each of these participants with 16 ounces of a high-fructose caffeinated soft drink or water (for the control group). This cycle was repeated for four times.
The participants were called back one week later and were made to perform this 4-hour routine again. However, this time, people who were given soft drink the last time were provided with water and vice versa.
The Effects of Soda on Kidney
The scientists measured a certain range of parameters in the participants both before and after their session. These parameters included core body temperature, blood pressure, body weight, and heart rate.
Moreover, they also tested for an increased creatinine level in the blood as well a reduction in the glomerular filtration rate, both of which are considered as the biomarkers of AKI. As the scientists had expected, people who consumed soft drinks had these markers present in their bodies.
Moreover, the participants with soft drink consumption were also dehydrated with an increased level of vasopressin- a diuretic hormone that enhances the blood pressure.
Scientists explained the result by proposing how soft drinks following an exercise in a hot environment does not allow the body to rehydrate. So, it is not suitable to use these sodas as a method of rehydration following an exercise.