Here's the secret to weight loss: It's all about crowding out, not cutting out. Crowding out is a term used in nutritional circles to describe how to eat in a healthy way so that you never even have the chance to feel hungry. You literally crowd out the junk you think you want to eat by choosing to eat key foods throughout the day so that you're always satisfied. Isn't that preferable to depriving yourself of foods and white-knuckling it all the way?
When you gradually add in nutrient-dense, fiber-rich foods, you simply stop feeling cravings. You run out of space in your belly for the old junk. Instead of craving, you feel full, fulfilled, and content.
Here's how it works: All you have to do to get started is to add healthier choices to whatever else you're already eating. Before you dig into whatever it is you really want to eat, have something with some natural fiber in it -- ideally, an apple -- because in all the medical literature, the one dietary component most associated with weight loss is fiber consumption. The reason fiber helps us control our weight is that it fills the belly yet yields few calories since fiber is, for the most part, not something that we can digest. It also slows down the digestion of food, so you get a slow and steady source of glucose sans the rollercoaster ride of blood sugar crazies and the cravings that follow.
Most Americans don't get enough fiber each day to meet their nutritional requirements. It's recommended that women get at least 25 grams of fiber per day on a 2,000 calorie diet -- or to be more precise, 14 grams of fiber per 1,000 calories consumed. Men are recommended to get 38 grams. However, the average American only gets about 15 grams daily. Twenty-five grams is actually at the low end of what your optimal fiber intake, so there's no reason not to aim higher. We humans actually evolved eating more than 100 grams of fiber a day, largely from wild greens. So back to that apple: How does an apple measure up in terms of fiber? Eating just one apple a day (skin on) will give you an average of 4.4 grams of fiber, about one-fifth of your daily need.
And apples don't have just any old fiber, they are a rich source of a particularly powerful kind called pectin. It's what's used as a gelling agent to make jams and jellies, and in our stomach it can delay stomach emptying through a similar mechanism. Researchers at UCLA showed that by swapping in pectin for regular fiber, they could double the time it took subjects' stomachs to empty from about 1 hour to 2 hours, which meant subjects felt full that much longer. And in another study published in the journal Nutrition, scientists found that instructing participants to eat an apple or a pear before meals resulted in significant weight loss.
The participants were told, in effect, to eat more food, to add the fruit on top of their regular diets, and what happened is that the fruit crowded out less healthy choices, they ended up eating fewer calories overall, and they started shedding pounds.
While singing the praises of the humble apple, though, I would be remiss not to mention the extraordinary health benefits associated with eating them. It seems the old adage, "an apple a day keeps the doctor away" just may hold truer than we knew.
A major review published in 2008 out of the German Cancer Research Center found that indeed, compared with those who eat less than an apple a day, those who eat one or more had less risk of oral cancer, cancer of the voice box, breast cancer, and colon, kidney, and ovarian cancer as well.
This makes sense given new research from Cornell showing that apple peels have potent antioxidant and growth-blocking effects on human breast cancer cells examined in a petri dish, and the higher the apple concentration, the fewer the cancer cells. And apples seem to work best against estrogen-receptor-negative breast cancer, which is much harder to treat than the receptor-positive kind.
How do apples do what they do?
There are three stages of tumor formation. Carcinogens cause the initial DNA mutations (the initiation stage), and then oxidation, inflammation, and hormones cause it to grow (the promotion stage); finally, metastasis occurs, in which the cancer spreads throughout the body. Which steps have apples been found to block? All of them. Apples not only have antimutagenic, antioxidant, and anti-inflammatory effects, but they may even enhance our immune systems to help clear out any budding tumors before they get their start.
So if you're rooting around for something to eat, grab an apple while you're looking, and usually by the time you're finished eating it, your hunger will have been sidelined; it's crowding out at its best! Have it in the midmorning, in the afternoon, or before a meal; it's entirely up to you. But before the day's end, do eat an apple. Not apple juice or applesauce (and certainly not apple pie or an apple muffin!). Just a good ol' whole apple. Any kind will do. You might just be pleasantly surprised at how the weight starts coming off and your health begins to soar!
For more on how to lose weight easily and healthfully, please check out The Lean: A Revolutionary (and Simple!) 30 Day Plan for Healthy, Lasting Weight Loss.
 Di Lorenzo C, Williams CM, Hajnal F, Valenzuela JE. "Pectin delays gastric emptying and increases satiety in obese subjects." Gastroenterology. 1988 Nov;95(5):1211-5.
 Conceicao de Oliveira M, Sichieri R, Sanchez Moura A. "Weight loss associated with a daily intake of three apples or three pears among overweight women." Nutrition. 2003 Mar;19(3):253-6.
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