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10 Incredible Reasons Why Diets Work

"Dave, I'm done dieting," my friend Tammy told me a few weeks back.

She'd heard that certain contestants from The Biggest Loser had gained all their weight back. "They had personal trainers, strict meal plans, and even a cash prize—if they can't keep the weight off, how can I?"

"Tammy," I said, "Those contestants were on a reality show. But the reality is, diets work. To lose big, you simply have to know which ones to choose."

As a health and fitness professional for the last two decades, I know the right diets to choose. I've spent my career studying the best and worst plans, and was not surprised by The Biggest Loser news—the show utilizes extreme forms of exercise and controlled eating to generate results. That leads to high ratings, but sustaining such weight loss in real life is not realistic. In fact, lost among the headlines of the six-year study was the fact that the contestants mentioned didn't keep up with the eight hours of daily exercise, like they did on the show—how could they!?! And most experts, including those from the National Institutes of Health, would agree that weight loss above an average 1 to 2 pounds a week is difficult to sustain without a diet plan. Context matters.

In fact, the ultimate diet is one with a nutrient-rich, calorie-controlled plan that emphasizes lean proteins, fiber and healthy fats, like the ones developed by Nutrisystem.

If you're not yet convinced, read on to discover the 10 reasons why diets work—and for the safest, most-effective way to strip away belly fat and achieve the lean body you've always wanted, don't miss these essential 50 Ways to Lose 10 Pounds—Fast!

Reason #10 Why Diets Work

They Reduce the Most Dangerous Kind of Fat

While researching Zero Belly, I discovered that belly fat—what scientists call "visceral fat"—is the most dangerous fat there is: dangerous to your heart, dangerous to your brain, dangerous to your love life, and even dangerous to your wallet. If you let that fat stay there, growing and making you sicker, you will live fewer years (and fewer happier years), and you will drain your savings combating the damage belly fat does to your health and well-being. That's why, before every meal, you should ask yourself three essential questions: "Where's my protein? Where's my fiber? And where's my healthy fat?" Apply those questions to any diet plan and you know you're making the right choice.

Reason #9 Why Diets Work


They Stop You From Clowning Around

If you order most of your meals through the mouth of a clown, it may be a sign that you're not giving your body the nutrients it needs, says registered dietitian Cassie Bjork. And it may be a sign you're on the wrong diet. "Many diets cut fat since it's higher in calories than protein and carbs, but this tactic can backfire by increasing cravings," she says. That's why one of my key questions is, "Where's my healthy fat?" "A simple way to keep cravings at bay is to add a couple of tablespoons of avocado, olive oil, nuts or seeds to all of your meal and snacks," says Bjork. "These healthy fats will keep your blood sugar levels stable and ward off sugar cravings, which will ultimately aid weight loss!" Speaking of fat, torch the flab off your belly by indulging in The 30 Best-Ever Fat-Burning Foods!

Reason #8 Why Diets Work

They Kick the Junk to the Curb

It's called junk for a reason. Binging on processed foods high in salt and fat—even if it's just three times a week—will not only cause you to gain weight, but it can also reduce beneficial fat-burning gut bacteria. Dr. Margaret Morris from Australia's University of New South Wales conducted a study on rats and explained, "While these findings are yet to be replicated in humans, those who are strict with their diet during the week may be undoing all their good work by hitting the junk food over the weekend." A good diet plan with a solid schedule will help you find a balanced approach to eating, and balance out your gut.

Reason #7 Why Diets Work

They Allow "Good" Carbs

Grains get a bad rap because of their carbohydrate content. That's why, when you're searching for a diet, stop thinking of "grains" or "carbs" and start thinking of healthy fiber. The right fiber sources provide your body with energy and help to feed lean muscle mass while keeping you full all day. In addition to filling fiber, staples like beans, lentils, oats, quinoa, and brown rice contain magnesium and chromium—two incredibly important nutrients that combat cortisol (a stress hormone that directs fat to be stored around the waist) and keep down insulin production. Find a diet that allows these types of fiber, and make sure it includes these mouthwatering 25 Best Carbs for Weight Loss!

Reason #6 Why Diets Work

They Teach You the "Right" Calories

You're not in Calculus class anymore, so don't stress about counting calories. But diets that revolve around "calorie control"—ala Weight Watchers or Nutrisystem—work, especially if you learn where your calories are from, and when to eat them. For example, protein consumption should be spread evenly throughout the day. Why? Studies show those who stagger their consumption lost more weight and were more apt to maintain their fit figures than those who skimped on protein at certain meals. Calories from protein are also different than calories from fats or carbs. In addition to boosting satiety, protein has a high thermogenic effect. That means your body burns off a fair percentage the meat's calories as you're digesting them—and post-meal calorie burn spikes by as much as 35 percent!

Reason #5 Why Diets Work

They Save You a Ton of Money

Weight gain costs us a lot of money—and not just in ripped pants seams and popped skirt buttons. In fact, obese men spend on average an additional $6,518 more in annual healthcare costs than normal-weight men. For women, the burden is even greater: women fork over an additional $8,365 in potbelly penalties each year. In fact, by one estimate, obesity-related health care will cost Americans $190 billion this year alone. The more pounds you pack on, the greater the shadow you cast on your financial future. For delicious, affordable foods that will reduce your costs and keep you slim forever, Click Here to save $225 a Month on Groceries!

Reason #4 Why Diets Work

They'll Get You a Raise

Link up with the right diet, and you'll look better on LinkedIn: In a study published in the International Journal of Obesity, researchers gave participants a series of resumes with small photos of the applicants attached. What they learned was that starting salary, leadership potential, and hiring decisions were impacted negatively when the photo showed a person who was overweight—most severely in the case of obese women. How do the researchers know that weight was the deciding factor and not their experience or general looks? Because they used the same individuals, before and after weight loss surgery! And we can put real numbers against this prejudice. One study by researchers at the University of Florida found that the total swing between slender and stocky amounts to $598,425. Think going on a diet might be worth a cool 600 G's?

Reason #3 Why Diets Work


They Make You Feel Better Naked

Besides the obvious health benefits, most people actually go on diets to look good, and to feel confident when it matters most. But new research has discovered an even more sinister way in which belly fat, in particular, can harm your sexuality. In studies, women with visceral fat accumulation have been shown to have elevated secretions of cortisol, a stress hormone. Women who show an increase in cortisol in response to sexual stimuli have lower levels of functioning in certain areas of their sex life compared with women who show a decrease in cortisol. Good sex comes from less stress. Abdominal fat causes more stress, which causes bad sex. To increase your sex drive—and decrease your belly—click here to discover the essential 14 Ways to Lose Your Belly in 14 Days!

Reason #2 Why Diets Work

They Reduce Depression

Simple food choices can make the difference between feeling worse and feeling more stable, says research from a February 2015 study by Virginia Tech College of Agriculture and Life Sciences. Diets can help because a balanced one reduces your consumption of added sugars. A 2015 study of postmenopausal women demonstrated that an increase in added sugars in their diet was associated with an increased likelihood of depression. And in a study published the journal Diabetologia, researchers have found that when blood glucose levels are elevated, levels of a protein that encourages the growth of neurons and synapses drops. Cut the sugar, and you'll feel lighter—in more ways than one.

Reason #1 Why Diets Work


They Help You Live Your Happiest, Healthiest Life

A balanced life starts with a balanced diet. "Being tired or constantly fatigued is your body's way of conserving energy when it's not getting enough of what it needs," says Bjork. "It's a result of your metabolism slowing down—the opposite of what you want to happen for weight loss." Isabella Smith, RD, concurs. "When you don't eat enough protein, for example, the body will start to break down stored proteins in the form of muscle and other tissues. This can shrink your muscle mass, making workouts and everyday physical activities more challenging." Meal plans that include lean proteins, fiber and healthy fats will keep you—and my friend Tammy—go strong all day long. To live your healthiest and happiest life—and find the right diet plan for you—don't miss this science-packed list of the 50 Best-Ever Weight Loss Tips and start losing your belly today!

David Zinczenko
Dave is a globally recognized expert in health, fitness, nutrition, and weight loss and is the #1 New York Times bestselling author of 25 books in 15 languages. Read more about David