01/24/2013 08:11 am ET Updated Mar 26, 2013

The Power of Lemonade

Why do we make bad decisions? Why do we eat that extra cookie or choose a cheeseburger instead of a salad with grilled chicken? What are we thinking when we do things to hurt the people we love most (not to mention the stranger who did not deserve our outburst at the grocery store)?

It turns out there is nothing wrong with you when your stressful life turns into fatigue and you give in to temptation or overreact. Your brain has simply run out of gas.

Roy Baumeister is a social psychologist at Florida State University who investigates what affects our self-control and what we can do about it.

In one of his experiments that has explored the secret to willpower, two groups of students were given an impossible puzzle to solve. As they struggled with the challenge, he gave one group delicious chocolate chip cookies. He instructed the other group to resist eating the sweets and gave them radishes to munch on.

The findings have a very happy ending. On average, the group that ate the cookies struggled with the puzzle for 20 minutes versus only eight minutes for the radish eaters. That's right; when you're stressed or struggling with a bad day, you're supposed to eat cookies.

With experiments like this Baumeister and his colleagues have uncovered that both willpower and decision-making use the same energy source in the body. The reality of modern life is that most of us are fighting temptation three to four hours a day. Consider all the places you have to make constant choices: at work, online, at the store, with your family, in traffic, even on your smartphone. Your brain simply cannot fight the things you don't want to do and make the decisions that are best for you without eventually running out of gas.

The good news is that the fuel that keeps your brain active is simple: glucose. Glucose, sugar, is the energy that powers your cells. Your stomach breaks it down from food to fuel your brain and other systems. It's not that radishes are bad fuel. It's best to eat our vegetables; and, in times of great temptation or challenge, we need a hit of sugar our body can absorb faster.

Burn too much glucose without refueling and your brain can't make good decisions. This creates a situation where your brain thinks you are in trouble, which activates the stress response. The stress chemicals in your body make you feel worse and instead of having willpower, you just try to get away from the uncomfortable feeling. Often, we get away from the bad feeling with the easy pleasures that soothe us: cheeseburgers, martinis, chocolate, or a cigarette. Just the mention of these treats might have caused you to burn more glucose as you resist their siren call.

The best news, however, is that if you add a little glucose to your system, your willpower increases. This is the power of lemonade, or a peppermint, or a bite of chocolate. Ironically, the answer to those times when you don't want to go out for your walk or you feel like the only thing that will make the day better is a quart of ice cream is to eat a bit of something sweet or sip a cold, sugary beverage. It is a healthy amount of sugar that makes it possible for you to truly take care of yourself in the midst of a stressful life.

And you can take this scientific truth to a new level with a little self-monitoring. When do you find yourself feeling weak? Over two days, in a notebook write the times when you give in to temptation or feel unable to control yourself.

Then over the next two days, sip a few ounces of lemonade a half-hour hour before those times. Don't gulp it. Don't constantly drink sugary drinks. This research is not an excuse to gorge; rather, it is an invitation to strategically sip juice or eat a peppermint before you lose your will.

The best way to deal with your stressful days is to take advantage of lemonade's power; your brain will thank you with better decisions and a happier life.

For more by Jon Wortmann, click here.

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