Getting with the program could have unintended consequences.
Yeah, yeah, you know you should eat more fruits and veggies, but you’re craving a creative approach — perhaps, even (though you wouldn’t admit it) a gimmick. “Americans love a good fad diet,” says Whitney Linsenmeyer, a spokesperson for the Academy of Nutrition and Dietetics. Problem is, such diets often suggest closely adhering to rules about what to eat and not to eat that aren’t backed by science and historically have rotated in villainizing protein, carbs or fat. “With a lot of these, if you’re cutting out a food group or going very low or very high with any of the macronutrients, you’re going to be missing key nutrients in the diet,” she says. Before depriving yourself, here are some other lessons learned from making extreme dietary changes:
Food becomes an adversary.
When you unnecessarily demonize certain foods, or macronutrients — for instance, adopting a very low-carb diet or severe calorie restriction — experts say it’s natural to become fixated on what you can’t have, rather than nourishing your body, and they contend that changes your relationship with food in negative ways. “With fad diets, food tends to become an enemy or something to be wrangled in, rather than being seen as nourishment for our bodies and a joyful part of life,” says Linsenmeyer, an instructor in the nutrition and dietetics department at Saint Louis University.
It doesn’t result in sustained weight loss — if that’s a goal.
Before changing how you eat to shed pounds, consider how quickly you’re going to purportedly lose that weight. “A safe rate of weight loss is about 1 to 2 pounds per week,” Linsenmeyer says. “Any time we see a diet promising faster rates of weight loss than that, it’s a red flag.” Increasingly, some experts — including many “non-diet” dietitians — view any kind of dieting in the traditional sense as extreme, and something to be avoided. That reflects a broader shift to focusing on eating patterns — rather than strict adherence to dietary programs — and also comes in response to concerns about a range of unhealthy eating behaviors and diagnosable eating disorders. Food is but one factor, too; exercise, sleep and stress all affect weight and overall health.
You might be jeopardizing your health.
Highly restrictive programs like the keto diet, which significantly slashes carbs so your body will be forced to burn fat, have drawn much criticism from dietitians. “If someone was doing one of these extreme diets, they could be altering their metabolism, like in the case of the keto diet that’s mimicking starvation,” Linsenmeyer says. Another worrisome trend is so-called water fasting, which some people do to cut weight fast. “It’s essentially consuming nothing but water — just not eating for extended periods of time,” like 24 hours or more, she says. This can drastically alter metabolism and lead to dangerous drops in blood sugar or blood pressure, heart arrhythmias or loss of consciousness, Linsenmeyer says.
You feel exhausted — day and night.
Sam Slattery now has energy to burn — which the college senior does as a student-athlete at University of Wisconsin-Eau Claire, where she runs cross country and track. But though she’s always paid attention to what she eats, when she went from more sensible steps like limiting sugar to more drastically cutting her caloric intake, especially carbohydrates, she felt absolutely drained. “I was exhausted all of the time,” she says. But that’s changed since she shifted to a more sensible approach. “I realized that I needed a lot more calories and many more carbohydrates, and a lot more protein, before and after I ran,” Slattery says. “I’ve had some of my best races since I’ve eaten more.”
Anyone who’s ever been hangry — or so hungry you’re angry — knows how not getting needed sustenance can tank your mood. Besides having her energy sapped by restricting her diet, Slattery adds that “I was very cranky — always in a bad mood.” Going on restrictive diets can cause you to have low energy, not feel satisfied or always feel like you’re hungry and tired, says Samantha Osterhaus, a registered dietitian in Minneapolis and blogger at livemindfullywell.com.
Sometimes close adherence to a diet — to manage diabetes, for example — is critical, and it may mean that going out to a restaurant with friends requires a bit more planning. But though even healthy dietary changes can raise social challenges, when you’re tired and miserable because your body isn’t getting the nourishment it needs, it follows that you may not be in the mood to be social. “I wouldn’t want to do anything or hang out with anyone,” Slattery says of her experience. While Slattery is connected with friends and family, for others social isolation is a serious health issue — and any changes that make a person more antisocial can feed into that.
You can’t think straight.
Among other symptoms, restrictive and particularly very low-carb diets — like keto — can cause confusion or mental fog. It’s not just being forever distracted or befuddled by what you’re supposed to eat that’s at issue, either, though that can take up precious mental bandwidth as well, dietitians say. “Glucose is the primary fuel source of your brain,” notes Kelly Toups, a registered dietitian nutritionist and director of nutrition for Oldways, a nonprofit food and nutrition education organization in Boston. “A lot of doctors are worried that starving the brain of its primary energy source might be harmful in the long term for people who don’t eat the keto diet for medical reasons.”
It increases your cravings.
The simplest way Osterhaus puts it to her clients is that “it’s kind of like the big red button phenomenon, where the second that you tell yourself you can’t have something, that’s going to be what your body craves.” Not only can unnecessary dietary restrictions fuel an unhealthy relationship with food, when a person does “give in,” it can lead to overeating, experts say. A better way: “giving yourself permission to have food — all foods,” says Hannah Turnbull, a registered dietitian nutritionist in Denver and blogger at NourishedwithHannah.com. The point, experts say, is to strike a balance: emphasizing things like fruits, veggies, whole grains, beans and nuts, like with the traditional Mediterranean diet, instead of hard-and-fast exclusions.
You don’t feel good about yourself.
Before becoming a dietitian, Turnbull says she dabbled in dieting and struggled with disordered eating, from being really restrictive to not eating enough food. Today, she focuses on helping clients find that pleasure and joy in eating, rather than going on diets to try to manipulate their body or restrict foods to feel more in control. “Because it’s not about being ‘good’ or ‘bad,’ it’s about taking care of yourself,” Turnbull says. Dietitians stress the importance of focusing on the bigger picture, which goes beyond what’s on the plate. For those who suspect they may have an eating disorder or suffer from body image issues, experts say it’s critical to seek help from a mental health professional.
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