Healthy Living

The 3 Biggest Reasons Your Diet Isn't Working

Plus, easy fixes to ensure your weight-loss efforts actually stick.

If you had a nickel for every time you went on a diet … Or, scratch that, if you actually lost a pound every time you went on a diet, well, you'd have no reason to diet!

Unfortunately, for a lot of people, diets tend to cause more frustration than actual weight loss. And the reasons are way simpler than you might imagine. In the end, virtually every diet fail comes down to three simple factors, according to nutritionists. Avoid them, and you'll be well on your way to weight-loss success.

Fail No. 1: You've Picked a Diet You Can't Follow Forever

"The No. 1 reason why diets don't work is because they are not sustainable for the long term," says nutrition and food scientist Danielle Starin, director of nutrition for the Nutritionix nutrition database. That applies not only to drastic juice cleanses as well as fad and deprivation diets, but to otherwise healthy eating strategies that just don't fit your individual lifestyle or preferences.

So what does "long term" mean? Way more than a few weeks or months until you've lost the weight – it means for life, she says. Otherwise, you'll gain it all right back. Sound familiar? Research from the University of California–Los Angeles shows that while most people can lose about 5 to 10 percent of their weight on just about any diet, on average, they end up gaining it all back – and then some.

The Fix: If you can't see yourself following your current meal plan for the rest of your life, throw it out the window and brainstorm some healthy eating changes you could actually stick to for years to come, Starin says. The weight loss is bound to happen more slowly that it will on a crash diet, but it'll be longer lasting. Plus, as you get comfortable with whatever your healthy changes may be – eating five servings of fruit and veggies per day, say, or cutting out sugary sodas – you may decide you want to make other healthy swaps, too. With this strategy, over time, you'll just keep getting healthier and healthier.

Fail No. 2: You're Eating Too Few Calories

To lose weight, you need to burn more calories than you're taking in each day. But that shouldn't be by that big of a margin, says registered dietitian Wesley Delbridge, spokesman for the Academy of Nutrition and Dietetics. After all, while the U.S. Department of Agriculture guidelines state that the average woman needs between 1,600 and 2,000 and the average man needs between 2,200 and 2,800 calories per day in order to maintain a given weight, as a general rule, eating any fewer than 1,200 or 1,400 calories a day (depending whether you're a man or woman) is not only dangerous to your health, but it can counteract your weight-loss efforts, Delbridge says. When you cut your caloric intake too low, your body dramatically slows its metabolic rate and begins to hold onto any sugar and fat it can, rather than burn it, he says. Basically, it thinks you're starving, so it does everything in its power to hang onto whatever you do consume, he says. What's more, with not enough food to fuel your biological processes, your body also begins to break down muscle, your metabolic powerhouse, for energy. The result: a lot of hunger and a scale that won't budge.

The Fix: Starin recommends using the Food and Drug Administration and National Institutes of Health body weight planner to calculate how many calories you need. You might be surprised the amount you need to eat, not cut, in order to lose weight!

Fail No. 3: You're Not Exercising

Sure, they say weight loss is 80 percent diet and 20 percent exercise, but if you're only dieting, the sad fact is that your metabolism is slowing. Your body mass and weight largely determine your basal metabolic rate, the amount of calories you burn just sitting on the couch all day. And, since it takes more fuel to run an SUV than a moped, the more weight you lose, the fewer calories you'll burn per day.

What's more, whenever you cut calories, you lose at least a little muscle along with fat (although if you cut calories too far, you'll lose a lot). And since muscle is the key to stoking your metabolism, any muscle lost is counteracting your weight-loss efforts. That's why muscle-building exercise is vital to any weight-loss plan, and trying to lose weight without it just won't pan out, Delbridge says. Case in point: In one yearlong Obesity study of 439 overweight and obese women, those who tried to lose weight by combining both diet and exercise ended up losing nearly 30 percent more weight than those who dieted alone.

The Fix: Pick up the weights to lose weight. Time after time, research shows that strength training is the key to fat loss. Case in point: In a recent Harvard School of Public Health study of more than 10,500 healthy men, those who regularly performed strength training over the course of 12 years gained significantly less belly fat than did aerobic exercisers.

The 3 Biggest Reasons Your Diet Isn't Working was originally published on U.S. Health News & World Report.

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