Not very, the experts say.
Here's why: Resolution-makers set unrealistic, unattainable goals. Many times, they make broad, sweeping statements. They don't prepare or research enough to take on the new challenge. Or maybe they just don't think enough happy thoughts.
"We've learned that repetition is important," Manevitz said. "You're essentially trying to rewire your brain. It takes 21 days to form a new habit, and six months for it to become part of your life."
That means doing - or even just thinking about - your new activity every day.
"Having positive emotions helps you make those new neuroconnections," Manevitz said. "If you're visualizing exercising, write down your resolution that, `Tomorrow I'm going to do the exercise. I feel really good about it!'"
Talking about it can help, too.
"The best thing for most resolutions is support," said Constantine Ioannou, vice chairman of psychiatry at Nassau University Medical Center in East Meadow. "Even announcing that you have a resolution, that people can be aware of what you're trying to change, is useful."
Most people stray from their best intentions because their resolution is flawed to begin with, the doctors said.
"Break down the larger resolution into smaller, more controllable pieces," Ioannou said. Instead of radical changes, consider smaller goals that are easier to achieve, he said.
Instead of saying, "I'll be more organized," resolve to buy a planner and organize your desk.
The real lesson here, the doctors said, is that we should teach kids good habits so they won't be faced with the daunting task of kicking bad ones as adults.
"Once these habits are formed, they're very hard to break," Manevitz said.