Not Losing Weight? Here's Why

There's no denying our numbers are dismal: Two-thirds of American adults and nearly 30 percent of children are overweight or obese. What's more, according to a recent worldwide study, our country has some of the highest rates of overweight and obese citizens in the world.

This might seem ironic, given we're a nation supposedly obsessed with eating right. Just check out all the newfangled diets -- such as gluten-free, wheat-free, high-protein, low-carb and Paleo. And yet none have made a dent in the rates of obesity. In fact, the average American adult now weighs 23 pounds more than his or her ideal body weight, according to the Centers for Disease Control.

The popular diets today often blame weight gain on single nutrients or food groups, such as carbs and bread, but these diet approaches aren't supported by rigorous human clinical trials. Plus, the opposite may be true. In fact, a review of 19 studies with more than 3,000 subjects published in PLoS One found that low-carbohydrate and high-carbohydrate diets don't differ in the amount of weight lost in the first few months or for up to two years after the initial weight loss. And another recent study found that those who consumed 47 to 64 percent of their total calories from carbohydrates -- considered a high-carbohydrate diet -- had the lowest risk of being overweight or obese.

Demonizing a specific food often distracts from the fact that to lose weight, calories count. Some 88 percent of Americans don't have a clue how many calories they should consume in a day, according to a national survey by the International Food Information Council Foundation. So it may not be surprising that we're eating more calories than ever, and more than we burn off.

According to the Center for Science in the Public Interest, Americans eat about 2,535 calories a day, up from 2,075 calories in 1970. The extra 460 calories are coming from most food groups (minus produce), such as fats and oils; added sugars; protein; and alcohol. Eating a bit more from all these different sources adds up to a significant increase in total calories and, ultimately, weight gain.

A Dietitian's Reality Check on Weight Loss

Here's my advice to all my clients who are struggling to peel off pounds:

-- Know your calorie requirements. You need to know how many calories you should be eating to maintain your current weight so you can reduce that number, and hit that target to promote weight loss. Here's a simple energy calculator from Mayo Clinic.

-- Perfect your portions. When we're served large portions of food or beverages, we consume more calories. Using smaller plates, bowls and silverware is an effective way to slash calories, In fact, a recent review of 72 studies found you can easily cut about 16 percent of your daily calories without even feeling deprived.

-- Prepare more of your meals. Each meal eaten away from home will cost you an additional 200 calories to your daily calorie budget, according to a recent report. Studies consistently show that people who eat out frequently are more likely to be overweight or obese. I tell my clients to eat out (or get take-out) no more than two meals per week.

-- Limiting added sugars and liquid calories. Added sugars and calories from beverages don't contribute to satiety, so removing them from your diet won't leave you feeling famished. (Alcohol is considered a real diet-wrecker because it's high in calories, stimulates your appetite and chips away at your willpower.)

-- Enjoy a variety of foods. The most satisfying way to eat includes a variety of foods from all five food groups -- fruits and veggies; breads, cereals and grains; dairy; proteins such as meat, poultry and fish; and healthy oils. If you get too restrictive or start eliminating food groups to cut calories, chances are you won't be able to stick with your program for too long.

-- Focus on quality calories. If your diet is comprised of the best options within each food group, you will naturally keep added sugars and unhealthy fats to a minimum. For example, within the dairy food group, buy low-fat and with no or limited added sugars. For grain-based foods, look for whole grains or grains with no added sugars and plenty of fiber. Keep meats lean and fats should be unsaturated.

Julie Upton, MS, RD, is a registered dietitian and communications expert specializing in food, nutrition and health. Ms. Upton is a nationally recognized journalist who has written thousands of articles for national newspapers, magazines and e-media including The New York Times, The Huffington Post, U.S. News and World Report, Prevention, Shape, Health, Good Housekeeping, Redbook and Men's Journal. She is co-author of "The Real Skinny: Appetite for Health's 101 Fat Habits and Slim Solutions" (Penguin 2013) and "Energy to Burn: The Ultimate Food and Nutrition Guide to Fuel Your Active Life" (Wiley 2009). Upton co-founded Appetite for Health, where she blogs daily about nutrition, fitness and health.