The Potassium Effect

BANANAS! Did I guess what you were thinking? I sure hope so. I know for many many years I considered ‘potassium’ and ‘bananas’ to be synonymous.

A lot of the things I mention about potassium will be similar to those I mentioned about sodium; being another electrolyte, potassium (sometimes seen as K+) is also involved in fluid balance. However, unlike sodium, potassium is found inside, not outside our cells. Once again, water likes to be wherever there is less ‘stuff’, so it will move in and out of cells according to the number of electrolytes.

Again similar to sodium, potassium is heavily involved in muscle contraction and nerve impulses. There is a pump inside of our bodies called the Sodium-Potassium pump. This pump moves sodium and potassium across the membranes of our cells. I heard some crazy statistic from my high school anatomy teacher that upwards of ½ of our DAILY energy output goes to fueling the S-P pump. It wasn’t until college that I figured out why. Without the S-P pump in our body, our nervous systems wouldn’t work—neurons simply wouldn’t fire, meaning our muscles wouldn’t contract and our heart wouldn’t beat. The exchange of these electrolytes across our cell membranes creates an electrical current that allows our neurons to fire. So basically…without the S-P pump, we would be dead. Which is a super scary thought! Our body depends so much on this process that functioning isn’t possible without it. Eat your bananas, people!

Another job of potassium is to maintain the pH of your blood. Though pH can be a bit complicated at times (I took an entire semester of chemistry where all we talked about was pH…and how to make atom bombs…), here is a very very basic definition: the more ‘positive’ molecules there are, the more acidic a solution is; the more ‘negative’ molecules there are, the more basic a solution is. Therefore, when your blood pH gets out of the normal zone (somewhere around 7.35), the concentration of K+ is altered to get it back to 7.2.

Besides blood pH balance, potassium has another role with blood health—it lowers blood pressure! Unlike sodium, which can raise blood pressure, potassium has this awesome ability to help the kidneys get rid of excess sodium in the body; therefore, reducing blood pressure.

If you have ever been to a doctor’s office and been put on a reduced-sodium diet, I am sure the doctor prescribed foods high in potassium such as…wait for it…FRUITS AND VEGETABLES! To any who struggle with high blood pressure, does this sound familiar at all? Fruits that contain a lot of potassium include: tomatoes (Are tomatoes considered fruit? I still don’t know the answer to this question), bananas, and watermelon. Vegetables that contain potassium include: tomatoes (in case they are actually a vegetable), baked potatoes (including sweet potatoes), kale, and cabbage. Non fruit and vegetables sources include: yogurt, milk, and beans. I hope at least some of these foods make it into your eating plan every day because they are SO yummy!

And here is a tip for those of you who love to exercise…if you eat a banana an hour or two before you vigorously exercise, it reduces the number of cramps you get. I did this during my last race—I had a banana about two hours before I raced. Though the race didn’t go particularly well, I didn’t have leg or back cramps…and I usually have those!

Once again, it’s amazing how much food can help us.