We’ve written in the past about some of the exciting studies surrounding a pretty unexciting product: beet juice. Several sources have found that a shot of the nitrate-reach beet juice could possible improve endurance and power in athletes when taken a few hours before a workout. And, thrilled by the idea of a legal, non-stimulant, completely healthy performance enhancer, many athletes from various sports have stocked up on beet juice shots.
Beyond athletes, though, some patients with high blood pressure have started asking their doctors if they should start taking beet juice as well. All of this hype is based on the theory that beet juice works by expanding your blood vessels, thereby decreasing blood pressure and increasing the amount of nutrients that can reach your muscles – fueling them for more activity.
A new study from Penn State University, though, questions this theory.
Not What We Thought
First off, let’s be clear: This study was not designed to test the performance-enhancing benefits that have been reported from beet juice. Instead, the researchers were trying to investigate the exact mechanism that causes those benefits. As mentioned above, it was previously thought that the high concentration of nitrates in beets led to an increase in nitric oxide – a vasodilating gas that has become a popular preworkout supplement over the past few years.
In this study, however, the team measured the amount of blood that flowed through the brachial artery in the forearms of their subjects during grip exercises. Surprisingly, there was no change in the the width of the artery when the subjects were given beet juice.
The researchers were careful to note, though, that this lack of dilation was not caused by a lack of absorption. Basically, this means that the nitrates in beet juice do get absorbed and do get converted into nitric oxide. But, for whatever reason, it does not result in the vasodilation that everyone expected.
Interestingly, the beet juice did result in a beneficial softening of the arteries which can result the risk of cardiovascular disease.
The researchers did note that the results of this study were limited by the test group. The subjects use here were young and healthy, with very healthy cardiovascular systems. This shows that beet juice likely does not act as a vasodilator in athletes. However, the study did not look at older individuals, or those with per-existing cardiovascular conditions, so more research is necessary to see if the juice could be useful in a clinical setting.
Also, the exercise intensities used in the study were limited. It is possible that higher intensity activities would have gotten different results.
In Application
So this study does not necessarily debunk the use of beet juice as a performance enhancer but it does show that the juice probably does not work the way everyone thinks. Remember, the study did not even look at athletic performance.
If you have taken beet juice in the past and benefited from it, you aren’t doing yourself any harm. The juice is a rich source of micronutrients that can surely improve various facets of your health.
Sources
http://www.sciencedaily.com/releases/2015/01/150119083300.htm