Suzanne Somers: Sexy Forever Diet (PICTURES)

(CBS) Suzanne Somers is back. And this time she's not working on your thighs, but your whole body, at least if you're over 40.

The former "Three's Company" star who had a second turn at fame with her Thighmaster infomercials from the 1990s, has a new book, "Sexy Forever: How to Fight Fat After 40," and isn't shy about sharing what she feels are the secrets to staying fit, healthy and sexy as you age.

In an editorial she wrote for the "Today" show, Somers takes aim at processed foods, transfats and the right type of proteins to eat.

"Don't be afraid of real food," the 64-year-old writes, "foods that come from nature, not man-made foods, not fake foods, not any foods with chemicals."

Somers believes that food additives, hormones fed to animals and bad fats all build up in the body as toxins. Cleaning them out, she says, is the only way to get the body ready to lose weight.

"Losing weight without learning to eliminate chemicals is like a merry-go-round," she writes. "And it's why dieting doesn't work. Plus the toxic load makes it more and more difficult for people from age forty on to lose weight."

Sounds good, but some dieting professionals are not fully on board.

"There is no proof to the theory that removing toxins helps you lose weight," says New York-based dietitian Marisa Sherry, "However choosing not to eat chemicals in your food is a good idea."

"Our bodies are designed to digest food," she adds. "Adding unnatural chemicals forces our body to do more work."

Somers advocates grass-fed beef, organic, or at least, antibiotic-free poultry, and steering clear of partially hydrogenated oils often found in margarine and manufactured baked goods.

She's also says to watch out for labels that sound healthy but might not be. Chicken broth, soy protein, and soy isolates, among others, don't sound so bad for you, and in fact might be pretty good, but they also might contain flavor enhancing chemicals like MSG, she warns.

More at SuzanneSomers.com.