'Smoothie off' 3 sizes

We can all appreciate a quick and tasty breakfast-and even more so if it kills hunger and whittles our waists. The easy key? Smoothies made with healthy fats like avocado, flaxseeds and coconut oil. "The fats add a critical nutritional piece," says Harvard-trained wellness expert Eric J. Rosenbaum, M.D. In fact, when researchers had folks sip drinks that were rich in healthy fats as breakfast, their hunger vanished for hours afterward and they shed up to 18.5 pounds in 12 weeks. More proof it works: Texas empty-nester Mollie Sparks, 60, says fat-rich smoothies were her go-to as she reversed constant fatigue and dropped 42 pounds. Read on for Mollie's inspiring story and to discover how fat in smoothies helps melt fat off bellies, hips and thighs.

-  KATE ARCELL

• Top docs rave about a delish secret ingredient helping women like Mollie Sparks slim down without hunger

One of the best things about smoothies is how easy they are to load with superfoods we often skip. Case in point: Most deliver 2 to 3 servings of fruit and veggies—enough to lower depression risk by 31%, heart disease risk by 40% and diabetes risk by 61%. You can also whip in protein, extra fiber and, of course, healthy fat. So a daily smoothie “covers a lot of sins and gaps in a person’s diet,” says Dr. Rosenbaum. One study found smoothie drinkers are 12 times more likely to be well-nourished than typical dieters. Impressive!

And that’s any smoothie. Adding healthy fats takes ’em to the next level, since dietary fat helps us extract more crucial nutrients from food. For example, we absorb a lot more wellness boosting vitamin D, vitamin K and beta-carotene from fat-rich smoothies.

And while any fat can do this, Dr. Rosenbaum wants you to be choosy. Because chemically processed fats used in packaged and fast food break down in a way that damages cells. By contrast, all-natural or minimally processed fats do amazing things inside us—like feeding our brains and soothing away inflammation. Best bets: avocado, flaxseed, coconut oil plus olive oil, nut butter and whole nuts/seeds.

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