Revolutionary idea? Nah. But for Kirstie Alley, scaling back on the quantities at every meal was key. “It took me four months to really know that I didn’t need to eat huge amounts,” says the actress, 56. Ashley Borden, an L.A.-based fitness and lifestyle consultant who has worked with Christina Aguilera, Mandy Moore and Penny Marshall, says that a serving of lean protein should be about the same size and thickness as the distance from your wrist to the tip of your longest finger.

Give the OK to Carbs

“I’m a carb queen,” says Kirstie. The trick to keeping them on the menu — a must for the star — is trading overprocessed carbs for ones that give you more bang for your buck. “Multigrain carbs like yams, oatmeal and rice take a long time for your body to break down and they have a lot of nutrients, so you’ll feel fuller longer,” says Borden.

Get Out of Temptation’s Way

“If you put tempting foods out, you’re going to eat them,” explains Kirstie’s Jenny Craig weight-loss consultant Tania Azar. “The focal point of activity in Kirstie’s house is her kitchen, so she makes sure to always have a big bowl of fruit or some fresh veggies handy.”

Borden recommends employing the same principle in restaurants: “Politely ask the waiter not to bring over any bread.” That way, there’s no chance of accidentally scarfing down three rolls before dinner without even realizing it.

Water Works

Kirstie chugs about 64 ounces (eight plastic bottles) of the clear stuff per day, which keeps hunger at bay and flushes toxins out of the system. One super-easy way to get more H2O: Seek out foods that are high in water content. For example, “watermelon is a better choice than a banana,” says Borden. (Dark green lettuce, cucumber, asparagus and bell peppers are also filling, water-packed options.)

Catch Those Zzz’s

“I’ve learned something really important,” says Kirstie. “I need to rest and sleep well. I think this really, really, really helps the weight-loss process!” (Kirstie usually gets up at 5 a.m. and goes to bed at 10 p.m.) Borden confirms that sufficient beauty sleep is a must: “When you’re run down, your body will crave the wrong things — like sugar and caffeine — so you’ll spend the whole day crashing.”

Don’t Obsess Over Slipups

Every weight watcher has moments of weakness, and Kirstie is no exception. After a “bad” weekend or a few days without any exercise, she focuses on getting back on track — not wallowing in guilt. “It’s great to mess up and not beat myself up and not give up,” says Kirstie. “If it takes a year or two to lose the weight, and 98 percent of the time you’re spot-on, who cares?” Besides, depriving yourself of all your favorite foods all the time is just counterproductive, period. “If something is really worth it, I’ll eat it,” she says.