'Tis the season of dieting.

So many people are motivated to shed the pounds after the holidays and into the new year and many succeed.

Take Marshall Brain who lost 50 pounds in six months.

ABC News followed his journey on the Dukan Diet back in 2011. Before he started the Dukan Diet, when he was at his heaviest at 240 pounds, the extra weight caused everyday problems for him.

"It affects my mobility, it affects my ability to reach down and put my socks on, it affects my ability to get in and out of the car, it slows me down," said Brain.

But upon revisiting Brain two years later, the pounds were starting to pack back on. He plans to renew his weight-loss efforts in 2014, but according to some studies, up to 85 percent of people who try to lose weight fail. Recent studies say it's a matter of biology.

Related: US News lists best diets for 2014.

"Your body starts to secrete hormones that make you feel hungrier; the brain responds more to food cues telling you to eat those foods," said Dr. Rena Wing, a professor of psychiatry and human behavior at the Alpert Medical School of Brown University and the Miriam Hospital, and a co-founder of the National Weight Control Registry.

But there is an elite group of people who have beaten the odds.

They can be considered "super dieters." They've not only lost weight, they've kept it off for years.

More than 10,000 of them are being tracked in a database by the National Weight Control Registry.

"We've been able to study these individuals carefully and find out what strategies have been related to their success," Wing said.

The average member has lost 70 pounds and kept it off for six years.

"In order to lose weight and keep it off, you can't just follow a trendy diet for a few weeks. That's not gonna work. This has to be a lifestyle change a permanent lifestyle change and that's what the registry members are able to do," Wing told ABC News.

Related: Keep your New Year's resolution with the left-hand diet.

Steve Porter is one of those successful members.

"Losing the weight honestly wasn't that hard," Porter said. "Keeping it off and maintaining it is because there are always the pressures."

After initially losing 105 pounds, he's managed to keep off about 85 of those pounds for the last three years.

He attributes his success to exercise and keeping track of what he's eating.

"From a meal perspective, we plan our meals very carefully. Keep everything on an excel spreadsheet so I know what our meals are and it's posted on our refrigerator," said Porter.

Tracking meals is one among many things these successful dieters have in common.

Many of them follow these strategies:

Rule No. 1. Don't ever cheat. They never give themselves a break, not even on holidays or weekends.

Rule No. 2. Eat breakfast. The National Weight Control Registry shows that's one of the most common traits of those who succeed in keeping those pounds off once and for all.

Rule No. 3. Get on a scale every day.

Rule No. 4. Put in the equivalent of a four-mile walk seven days a week.

Rule No. 5. Watch less than half as much TV as the overall population.

Rule No. 6. Eat 50 to 300 calories less than most people.

And some good news: There is a point where it does get easier.

"The Registry suggests that if you can keep off the weight for two years, you're probably going to have a much better chance of keeping it off long term," said Wing.

Many Registry members say these behaviors are common traits but not something they necessarily do all the time.

What they do all time is be conscious and careful.

That would also describe Kalyea Moss, who has shared her weight-loss journey with ABC News for the past two years.

After initially losing the weight on the Rehab Diet and then gaining it all back, Moss struggled with her weight loss.

But she believes she has finally found the key to keeping the weight off, and it isn't by dieting.

"Just honestly truly changing my lifestyle," Moss said. "I really believe it's really you wanting to change your life because that's what it is. It's not about what you eat. There's so many things that play a part in people gaining and losing weight."

Inspired by her original Rehab diet experience with ABC News and living a healthy, long life for her 3-year-old son, she became a certified holistic health coach and calls herself The Curvy Health Coach.

She uses her experience and her knowledge of dieting to help other women change their lifestyles to lose the weight.

At 179 pounds, she is at her lowest weight as an adult and plans to lose even more weight.

While the "golden rules" are essentially the most common traits among the super dieters, one thing they will all consistently say is that this is not about going on a diet, which implies something temporary. It is about a long-term commitment to lifestyle change.

That's how they are losing the weight. That's how they're keeping it off.

ABC News