Every year, millions of people resolve to eat healthier or work out more or start a weight-loss plan. And every year, nearly 90% of these resolutions go unresolved. Several studies have been done on why people keep or break their New Year’s resolutions, and the reasons involved are a little more complicated than one might think.

One of the biggest influences on keeping a resolution is willpower. But it may not be in the way you think. Our brain’s ability to maintain our willpower can be hampered by several outside factors.

The first is our cognitive load, or how much we have on our minds at the moment. When researchers asked participants to memorize a short number or a long number and then choose between healthy food and junk food, participants with the longer number in their brains had a harder time resisting the junk food. Another study asked participants to do heavy mental tasks and then participate in a beer taste test. Participants who had to think harder ended up drinking more.

In addition, because our brain requires energy to focus, the less energy we have, the harder it is to maintain our willpower. This presents an obvious catch-22 in the case of weight loss. You must necessarily have willpower in order to consume fewer calories. But fewer calories mean less energy and thus less willpower.

Finally, it seems that focusing on the goal isn’t enough. You must also be distracted from any obstacles in your way. This is best seen in the famous “marshmallow experiment” by Walter Mischel. Children who successfully resisted the temptation to eat a marshmallow placed in front of them sang songs or played in order to distract themselves. Children who could not distract themselves were unable to resist.

So what does all this mean for you? That you’re destined to fail?

Fear not!

In order to achieve a health goal you’ve set for the New Year, consider the following:

• Willpower is not an innate strength you possess, but rather a quality that depends on how taxed the mind is.
• Don’t blame yourself when you fail, but look at the obstacles you need to overcome to do better next time.
• Remember that self-control is not limited and you were not born with a certain amount of willpower—it sounds silly, but you need to believe you can change!

Studies show that having faith in yourself and recognizing a need for greater willpower makes you more likely to succeed. You also need to have or obtain the skills needed to succeed (for example, looking up diet plans and exercise regimes if you’re trying to lose weight). Jumping in head first with willpower alone can only get you so far.

Researchers suggest these are the best ways to achieve your goals:

• Commit to making the change and be able to cope with any problems. (Don’t give up!)
• Make specific goals and keep track of progress. (Goals such as “I will eat at least five servings of fruits and vegetables a day” are better than “I will eat healthier.”)
• Start thinking about resolutions early and do the research to find out how to achieve them.

Happy New Year! And good luck to everyone trying to make a positive change in their lives!