There are literally hundreds of diets that have been promoted as the latest, greatest, and easiest way to lose weight. Unfortunately for those of us who try them, most of these fad weight-loss plans leave us eliminating foods, entire food groups, and the calories we need to fuel our hearts, brains, and nervous systems—not to mention they leave us feeling cranky, tired, and irritable. Recently I had pizza with a friend, and watched as she picked the cheese off the crust and ate only that, along with the pepperoni melted into it, to avoid those “fattening” carbs.
That got me thinking, by choosing these extreme diets in hopes of fitting into a pair of jeans, feeling better about ourselves, or whatever reason, could we actually be hurting our health? Could my friend’s low-carb diet be the real culprit behind her hideous mood swings? Is a low-cal lifestyle directly linked to the fatigue and headaches so many of us deal with? I did a little digging for some nutritional (not marketing-based) facts behind some of the most popular diet styles. What I found isn’t generally surprising (obviously eating only grapefruits isn’t good for you), but the specifics—which diets deprive us of which nutrients—could help anyone out of a rut toward more energy and less health problems.
1. Diet Culprit: Low- or No-Carb
You’re feeling: Sluggish, nauseous, dulled appetite
Add to your diet: 100 grams of complex carbs (at least)
By now we’ve all tried a low-carb diet (how could we not when Jessica Simpson said that was her secret?), but, as we also all now know, it’s not that simple. “When we restrict carbs, the body goes into a new metabolic state called ketosis, and starts burning its own fat for fuel,” says Lindsay Segal, a graduate student training to become a physician’s assistant. Granted, burning fat sounds like a good thing, but this is actually a dangerous state for the body to enter after a certain period. We usually burn carbs for energy, which then fuels the brain, heart, and all those other necessary systems. But when our body is in this new mode for too long (about two weeks), it produces substances called ketones, which can cause organs to fail and result in kidney stones and even kidney failure. According to the American Dietetic Association, ketones can dull the appetite, cause nausea, and even bad breath. Avoiding carbs—and the vitamins, minerals, and antioxidants you’d normally get from whole grains and fruit—means your body is missing out on a slew of cancer fighters. To avoid the negative effects of prolonged ketosis, add back at least 100 grams of carbohydrates every day.
2. Diet Culprit: High-Protein
You’re feeling: Tired, unable to concentrate
Add to your diet: Carbs and fat (in place of some of that protein)
Diets focusing on protein, protein, protein go hand-in-hand with the low-carb craze. These plans tell followers to eat between 30 and 50 percent of their calories from protein. The American Heart Association, the National Cholesterol Education Program, and the American Cancer Society, on the other hand, all recommend a diet with a much smaller portion of calories derived from protein. Why? “Eating too much really strains the kidneys, and can make someone prone to kidney disease later in life,” says Jenny Geyser, a certified personal trainer in La Jolla, California. “You don’t need as much protein as you think,” she says. Geyser says an egg or two at the beginning of the day and a serving of lean meat with dinner should provide the average woman with enough. Super high-protein lifestyles—especially when it comes from red meat, cheese, and other high-fat goodies—have been linked to high cholesterol and a heightened risk for heart disease and cancer. As if those aren’t enough reasons to substitute whole wheat bread for that ham and cheese omelet, these diets can be particularly harmful to women since they make it more difficult to absorb calcium. This means a higher risk for brittle bones and osteoporosis.
3. Diet Culprit: Low-Calorie
You’re feeling: Fatigue, constipation, nauseous
Add to your diet: A little fat, a little protein, and complex carbs
“Avoid any diet that calls for less than 1,200 calories per day,” says Lynn Davis, a Colorado-based nutritionist. Though doctors may sometimes recommend a very low calorie diet for obese, at-risk patients, this is only in severe circumstances and with close monitoring. The ADA notes that people severely restricting calories often feel overly tired, constipated, and nauseated due to an extreme deficiency in nutrients and energy. Another common—and more serious—side effect of these plans is gallstones. “For the body to be properly fueled and healthy, we need a variety of food from each food group, which is quite difficult to do when consuming so few calories,” says Davis. “Make sure each meal has some of each.”
