Coolsculpting

Dr. Grant Stevens and Laura Pietrzak demonstrate how Coolsculpting works on a client at The Institute at Marina Plastic Surgery in Marina del Rey. (Anne Cusack / Los Angeles Times)

TruSculpt

$800 to $1,000 for each treatment. (Two treatments may be required.)

This machine uses radio frequency to heat fat cells, causing cell death, or apoptosis, with fat cells being flushed away over the course of one to three months, resulting in a reduction of the underlying fat layer.

Just how much fat it eliminates is debatable. Although the treatment's website shows an ultrasound image of one patient who lost more than 25% of the fat after two treatments, Kouros Azar, a plastic surgeon in Thousand Oaks, says in the 200 treatments he has performed, he has seen an average loss of 1 to 2 centimeters of fat, or less than an inch.

Azar likes the machine because it is versatile enough to treat fat pockets all over the body, including the arms, thighs, above the knees and under the chin.

"I have found it to fill a huge void in our practice for non-invasive body contouring," Azar says.

Liposonix

Cost: $3,000 for one treatment

This device uses high-intensity, focused ultrasound to destroy fat cells without damaging the outer layer of skin. As with the other methods, your body eliminates this fat over two or three months, the machine's maker, Solta Medical, says. The results average about an inch of fat loss for the one-hour treatment.

As the treatment head is moved over your abdomen, patients can expect to feel discomfort, cold, prickling, tingling and warmth, which the company describes as "mild."

That's not how Stevens describes the process. "It's effective," he says. "However, it hurts like hell." Potential adverse effects after treatment include discomfort, bruising, redness and swelling.

Zerona

Cost: $2,500 to $3,000 for a series of six sessions

Promising to liquefy fat that can then be flushed away by the body, this low-level laser treatment has plenty of skeptics.

"It 100% does not work," Stevens says. "We have never seen any fat reduction with this." Studies on the company website promise an average loss of 3.64 inches on waist, hips and thighs if you follow the treatment regimen, which includes drinking lots of water, cutting out alcohol and caffeine, eating a healthful diet and exercising for 30 minutes a day.

Stevens is not alone in rejecting this treatment. The company that holds the license to Zerona recently filed for Chapter 11 bankruptcy protection after Zerona laser users began returning the machines earlier than expected and it could not make royalty payments to the laser's manufacturer.

Vanquish

Cost: Estimated at $700 to $800 per treatment.

Another highly anticipated, pain-free method of fat removal is coming out later this year. It promises to zap fat without even touching your skin.

Called Vanquish, this FDA-approved machine by BTL Aesthetics hovers over your skin, heating and destroying fat cells (without disturbing the skin) in four 30-minute sessions spaced a week apart.