The dawn of a new year has prompted millions of Americans to resolve to get in better shape. Nevertheless, many of those who make fitness resolutions find it a challenge to stick with weight loss plans or long-term health goals. And getting off-track with slimming ambitions happens to the best—even celebrities.

Award-winning actress Kirstie Alley lost an astounding 75 lbs. when she was a spokesperson for Jenny Craig from 2004 to 2007, but then subsequently fell off the weight loss wagon. Now, however, she's back on the nutrition program, and has achieved a remarkable 50lb weight loss since rejoining.

Alley "has ups and downs like everyone does. People think celebrities have trainers, chefs and that might be true for some but none of that guarantees success," said Monty Sharma, Jenny Craig's CEO, in an interview.

"At Jenny Craig we help thousands of members lose weight over time," he said. "And we recognize that on occasion life gets in the way and you have personal challenges. But when that happens we are standing by to get you get on track."

Sharma leads the weight loss program and the global exercise franchise Curves that has 6,000 locations in over 80 countries. When Jenny Craig and Curves merged in 2014, the transaction created a new company initiative that offers both fitness and wellness brands under one roof.

"Although these two brands continue to operate independently they have great synergies," said Sharma.

In 2013, food giant Nestle sold a stake in Jenny Craig to North Castle Partners, a private equity firm focused on health and wellness businesses. At the time, analysts saw the diet company as an underperforming asset that was a prime candidate to be offloaded by the Swiss food giant.

Fast forward a year, and the company has more spring in its step. Late this year, nearly 60 new locations will begin to offer Jenny Craig alongside with Curves fitness programs, part of the strategy to tie the two brands closer together.

"We are really distancing ourselves from a do-it-yourself approach and sticking to what works for members: working towards goals on a one-on-one basis," said Sharma.

The CEO is in tune with the busy lives of the Jenny Craig member, and tries to keep things simple for clients who find weight loss–and the time to commit to a program–a real struggle. He says if you don't have 15 minutes a week to come in and talk to a coach, Jenny Craig offers an application to help for customer convenience. In keeping with the consumer friendly approach, diet coaches are also available by phone, and uses data to identify at-risk dieters.

"Jenny Craig holds you accountable," said Sharma. "We partner with members to teach them how to have a healthy relationship with food, exercise more and help them modify bad behaviors to get the results they want."

Still, the full menu of pre-prepared foods and counseling sessions doesn't come cheap. Jenny Craig enrollment begins at $99 a month, with an additional $19 a month for unlimited consultations that may vary among different plan options.

According to the USDA's Food Price Outlook, the average weekly food budget for a single woman between the ages of 30-65 can range from a $37 to $77. Jenny Craig foods can average nearly $115 per week–which doesn't include additional grocery shopping for fresh produce, let alone an outside monthly gym membership fee.

Not every woman has that kind of money, but Sharma stands firmly behind the results.

"This is the only program that worked for Kirstie," he said. "She's come, gone and done it again and we're really proud of what she's accomplished."

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