We've all received the well-meaning advice to "stay positive." The greater the challenge, the more this glass-half-full wisdom can come across as Pollyannaish and unrealistic. It's hard to find the motivation to focus on the positive when positivity seems like nothing more than wishful thinking.

The real obstacle to positivity is that our brains are hard-wired to look for and focus on threats. This survival mechanism served humankind well back when we were hunters and gatherers, living each day with the very real threat of being killed by someone or something in our immediate surroundings.

That was eons ago. Today, this mechanism breeds pessimism and negativity through the mind's tendency to wander until it finds a threat. These "threats" magnify the perceived likelihood that things are going—and/or are going to go—poorly. When the threat is real and lurking in the bushes down the path, this mechanism serves you well. When the threat is imagined and you spend two months convinced the project you're working on is going to flop, this mechanism leaves you with a soured view of reality that wreaks havoc in your life.

Maintaining positivity is a daily challenge that requires focus and attention. You must be intentional about staying positive if you're going to overcome the brain's tendency to focus on threats. It won't happen by accident.

Positivity and Your Health

Pessimism is trouble because it's bad for your health. Numerous studies have shown that optimists are physically and psychologically healthier than pessimists.

Martin Seligman at the University of Pennsylvania has conducted extensive research on the topic. Seligman worked with researchers from Dartmouth and the University of Michigan on a study that followed people from age 25 to 65 to see how their levels of pessimism or optimism influenced their overall health. The researchers found that pessimists' health deteriorated far more rapidly as they aged.

Seligman's findings are similar to research conducted by the Mayo Clinic that found optimists have lower levels of cardiovascular disease and longer life-spans. Although the exact mechanism through which pessimism affects health hasn't been identified, researchers at Yale and the University of Colorado found that pessimism is associated with a weakened immune response to tumors and infection.

Researchers from the University of Kentucky went so far as to inject optimists and pessimists with a virus to measure their immune response. The researchers found optimists had a much stronger immune response than pessimists.

Positivity and Performance

Keeping a positive attitude isn't just good for your health. Martin Seligman has also studied the connection between positivity and performance. In one study in particular, he measured the degree to which insurance salespeople were optimistic or pessimistic in their work. Optimistic salespeople sold 37% more policies than pessimists, who were twice as likely to leave the company during their first year of employment.

Seligman has studied positivity more than anyone, and he believes in the ability to turn pessimistic thoughts and tendencies around with simple effort and know-how. But Seligman doesn't just believe this. His research shows that people can transform a tendency toward pessimistic thinking into positive thinking through simple techniques that create lasting changes in behavior long after they are discovered.

Here are three things that I'll be doing this year to stay positive.

1. Separate Fact from Fiction

The first step in learning to focus on the positive requires knowing how to stop negative self-talk in its tracks. The more you ruminate on negative thoughts, the more power you give them. Most of our negative thoughts are just that — thoughts, not facts.

When you find yourself believing the negative and pessimistic things your inner voice says, it's time to stop and write them down. Literally stop what you're doing and write down what you're thinking. Once you've taken a moment to slow down the negative momentum of your thoughts, you will be more rational and clear-headed in evaluating their veracity. Evaluate these statements to see if they're factual. You can bet the statements aren't true any time you see words like never, always, worst, ever, etc.

Do you really always lose your keys? Of course not. Perhaps you forget them frequently, but most days you do remember them. Are you never going to find a solution to your problem? If you really are that stuck, maybe you've been resisting asking for help. Or if it really is an intractable problem, then why are you wasting your time beating your head against the wall? If your statements still look like facts once they're on paper, take them to a friend or colleague you can trust, and see if he or she agrees with you. Then the truth will surely come out.

When it feels like something always or never happens, this is just your brain's natural threat tendency inflating the perceived frequency or severity of an event. Identifying and labeling your thoughts as thoughts by separating them from the facts will help you escape the cycle of negativity and move toward a positive new outlook.

2. Identify a Positive

Once you snap yourself out of self-defeating, negative thoughts, it's time to help your brain learn what you want it to focus on — the positive.

This will come naturally after some practice, but first you have to give your wandering brain a little help by consciously selecting something positive to think about. Any positive thought will do to refocus your brain's attention. When things are going well, and your mood is good, this is relatively easy. When things are going poorly, and your mind is flooded with negative thoughts, this can be a challenge. In these moments, think about your day and identify one positive thing that happened, no matter how small. If you can't think of something from the current day, reflect on the previous day or even the previous week. Or perhaps there is an exciting event you are looking forward to that you can focus your attention on.

The point here is you must have something positive that you're ready to shift your attention to when your thoughts turn negative. Step one stripped the power from negative thoughts by separating fact from fiction. Step two is to replace the negative with a positive. Once you have identified a positive thought, draw your attention to that thought each time you find yourself dwelling on the negative. If that proves difficult, you can repeat the process of writing down the negative thoughts to discredit their validity, and then allow yourself to freely enjoy positive thoughts.

3. Cultivate an Attitude of Gratitude

Taking time to contemplate what you’re grateful for isn’t merely the “right” thing to do; it reduces the stress hormone cortisol by 23%. Research conducted at the University of California, Davis, found that people who worked daily to cultivate an attitude of gratitude experienced improved mood, energy and substantially less anxiety due to lower cortisol levels.

You cultivate an attitude of gratitude by taking time out every day to focus on the positive. Any time you experience negative or pessimistic thoughts, use this as a cue to shift gears and think about something positive. In time, a positive attitude will become a way of life.

Bringing It All Together

I realize these three tips sound incredibly basic, but they have tremendous power because they train your brain to have a positive focus. They break old habits, if you force yourself to use them. Given the mind's natural tendency to wander toward negative thoughts, we can all use a little help with staying positive.