Your 6 Biggest Diet Mistakes

by Jessica Girdwain for SHAPE.com

These diet mistakes could be messing with your metabolismThese diet mistakes could be messing with your metabolismThere you are working so hard to drop pounds: busting your butt at the gym, cutting back calories, eating more vegetables, maybe even trying a cleanse. And although you can find experts to recommend all of these efforts, your plan may actually be foiling your weight-loss goals.

As contradictory and exasperating as it seems, some common diet mistakes can hamper your metabolism, your internal furnace that incinerates calories 24/7, whether you're sprinting in spin class or sitting on your derriere in front of the TV. That doesn't mean you should quit your gym membership and go buy a pint of chocolate chocolate chip. Keep up the work and keep losing with these easy fixes.

1. Eating a high-carb breakfast: You've been told over and over that people who eat a morning meal tend to have smaller waistlines, but some find that noshing in the a.m. actually makes them hungrier. If you can relate, it may be that the "healthy breakfast" you're eating-such as cereal and fruit-contains too many carbs, priming you to overeat later.

"When you have a sluggish metabolism, it's often a sign that you have some insulin resistance-your body is having a hard time moving sugar from your bloodstream into your cells for fuel, and when that doesn't work right, you feel hungry even when you're physically not," says Caroline Cederquist, M.D., an expert in nutrition and metabolism and medical director of BistroMD, an online diet delivery program. This is especially noticeable after you wake up. In the morning, insulin levels are high-eat a high-carb meal, and insulin rises even more, then nosedives quickly, leaving you ravenous by noon.

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The solution: Pair those carbs with protein to help slow down the blood sugar response. Aim for 30 grams of protein (a cup of cottage cheese or two eggs and a container of plain low-fat Greek yogurt) and about 20 to 30 grams of carbs (a medium banana, large piece of toast, or packet of instant plain oatmeal).

2. Skimping on protein: All day your body is going through a process called protein turnover, basically breaking down its own muscle tissues. Totally normal, but many women don't eat enough protein (which contains amino acids, the main "food" for muscles), to counteract this effect and properly maintain lean mass. Not good since the more muscle you have, the more calories you burn no matter what you're doing.

The solution: The RDA for protein for women is 45 to 50 grams, but Dr. Cederquist says that leaves women deficient and unable to keep their metabolisms optimally revved and burn body fat. Make sure to get 30 grams (about 4 ounces of chicken) at breakfast, lunch, and dinner, and 10 to 15 grams in snacks.

3. Eating less to lose weight:
Yes, you have to cut calories to fit into a smaller size. But as the number on the scale decreases, your metabolism can also take a dive for two reasons: First, although some of the weight lost is fat, some is calorie-torching muscle. Second, "your body has a 'comfortable' weight because we're genetically primed to fight starvation. As you're losing weight, your body tries to hang on to calories in order to get you back up to your baseline," says Robert Yanagisawa, M.D., director of the Medically Supervised Weight Management Program at Mount Sinai. You may also feel hungrier as your body tries to persuade you back to your set point. Luckily your body will gradually reset your weight to a new baseline, Dr. Yanagisawa adds.

The solution: Until your body stops sabotaging your weight-loss efforts, the most important thing you can do is load up on fruits and vegetables. Your GI system works overtime to break them down (torching a few extra calories), but most importantly, they're an effective way to fight this extra hunger by filling you up with low-cal fiber. Load half your plate with produce at every meal and eat a salad with vinaigrette before or after dinner. The salad slows down your eating speed, giving anti-hunger hormones the 20 to 30 minutes they need to kick in so you feel full and eat less at your meal-or are better able to resist dessert after, says Scott Isaacs, M.D., a metabolism expert and author of Beat Overeating Now!


4. Drinking diet soda:
It's a cruel twist of fate that something calorie-free can plump you out. "Studies show that artificial sugar stimulates the same hormonal and metabolic responses of real sugar," Dr. Cederquist says. As you eat fake sweetener, receptors in your brain and gut anticipate getting calories from sugar; in response, your body releases the fat-storage hormone insulin.

The solution: "Toss the calorie-free stuff and start eating real food," Dr. Cederquist says. You want to cut out diet soda out completely, but if you're a three-cans-a-day gal and don't want to quit cold turkey, start by cutting back to one can and always consume diet drinks with a meal. "That way your body gets the calories it's expecting, so there's less of an insulin response," Dr. Cederquist explains.

5. Not washing produce: Pesticides are not just insect killers, they're also endocrine disruptors. Because the endocrine system controls metabolism, exposure to certain chemicals can increase appetite, stimulate fat cells, and cause a sluggish metabolism, Dr. Isaacs says. Pesticide residue on produce (as well as any plastic packaging they come in) can throw off your hormone levels and even lead to weight gain.

The solution: Keep eating those fruits and veggies, but be diligent about washing everything, even "pre-washed" salad mixes and foods you won't eat the rind of, such as cantaloupes and avocadoes. Dr. Isaacs recommends submerging in a large bowl of water for one to two minutes, then rinsing under running water. Use a soft brush to scrub citrus and other foods with hard peels.

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6. Cleansing:
If there's one thing about juice fasts, you do lose weight pretty quickly. But most of that's water-and muscle tissues, Dr. Cederquist says. You probably can guess where we're going with this: When you deny your body the nutrients it needs by consuming too few calories and inadequate protein, your body will break down muscle tissue. "In the end, you'll just gain that weight back when you start eating again and maybe even more because you've lost muscle mass," she says. Some cleanses can be three weeks or a month, but many are just three days-enough time to damage your metabolism. Yikes.

The solution: Skip the cleanse completely.

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