155 pounds lost in 7 months — Is it safe?

The 15th season of NBC's The Biggest Loser concluded Tuesday night, but it's safe to say this edition hasn't been forgotten.

Rachel Frederickson, a 24-year old former competitive swimmer, weighed in at 105 pounds to win the Season 15 crown—a far cry from the 260 at which she tipped the scales when taping began in June.

Do the math—Fredrickson lost 155 pounds, or 59.62 percent of her total body weight—in just over seven months. While her rapid transformation won her the show's $250,000 grand prize, many experts have attacked the show and by extension, Frederickson's appearance—claiming that such rapid weight loss cannot be healthy or sustainable under any circumstances.

"I don't think I've ever been so uncomfortable watching the finale," read a tweet from one avid viewer. "Rachel just looks so sickly. She shouldn't be able to win."

What do local experts have to say about this sort of transformation?

"That's crazy," admits Kelly Strogen, MS, RD, LDN, registered dietitian at Club La Maison in Wayne. "It's certainly not healthy, and long-term, the weight loss is unsustainable."

Frederickson's supporters have conceded Strogen's second point, regarding the inability to sustain such weight loss, claiming that Rachel will certainly gain back some weight now that the show has concluded.

"Reality TV is not reality," points out Katie Cavuto, MS, RD, president of Healthy Bites Nutrition and dietitian for the Philadelphia Phillies. "There's more at stake than the satisfaction of losing weight."

That said, Cavuto feels it's unfair to quickly classify Frederickson as having an eating disorder, being only in it for the money, or in any other category.

"It is difficult to back extreme, rapid weight loss as it can be detrimental to the health of the individual," she allows.

While most people seem to agree that the rate of weight loss is unhealthy, the reality TV era has proven that people are willing to take some pretty serious risks in exchange for fame and fortune. So what would Kelly Strogen do if she met a client who was determined to duplicate Frederickson's feat? In other words, what can be done to reduce the unavoidable risk factors?

"There's really not a safe way to lose that amount of weight so quickly," emphasizes Strogen.

Strogen added that the exercise regimen practiced by The Biggest Loser contestants, combined with the drastic reduction in caloric intake needed to lose that amount of weight puts the contestant at risk for dehydration, malnutrition, even cardiac issues up to and including heart attacks.

"If someone becomes too thin, and is still exercising, the electrolyte imbalances can cause a heart attack," she continues. "So no, I can't justify any safe way to lose that amount of weight in such a short time."

Strogen says she never advises her clients to go below their basal metabolic rate—loosely defined as the amount of calories that a given individual would burn in one day with no activity whatsoever. "If you do that for too long, you're going to be breaking down muscle. There's no question she lost some lean muscle during this process."

If there is a silver lining here, it's that Frederickson should be able to put on at least some weight quickly, as the body's tendency is to hoard the available calories following the shock of such a sudden weight loss. But has Frederickson dodged a bullet? Is she out of danger now, or could there be long-term repercussions to her experience?

"Some experts believe that yo-yo dieting can lead to a higher body-fat percentage over the long haul," says Strogen. "For example, if she were to regain the weight, chances are she'd have a higher body fat percentage than she did previously."

In summary, Strogen says that weight loss should be achieved at a rate of 0.5 to 2 pounds per week.

"I hardly ever see anyone who can sustain weight loss at two pounds per week," she admits. "5, 6 pounds a week? Crazy."

In fact, Strogen agreed that if Rachel Frederickson wanted to lose 155 pounds, she would've been better off losing one pound a week over three years. "She'd have a better chance of keeping the weight off that way," she adds.

But she'd also be $250,000 poorer. Was it worth the risk?

"The whole thing feels sad to me," concludes Cavuto. "She was criticized for being overweight. Now she is criticized for being too thin. It's one of the downfalls to being in the public eye."

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