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- INSIDER polled 1,102 people about their New Year’s resolutions, and many said their 2019 goal was diet-related.
- According to the poll, the most popular diets people want to try in 2019 are: low-carb, calorie restriction, keto, low-fat, and eating less meat.
- INSIDER asked three dietitians if these diet strategies can help people lose weight or be healthier.
- They said that, for most diets, the answer depends on what you eat in place of the foods you eliminate.
As 2018 draws to a close and end-of-year-celebrations ramp up, most people find themselves navigating numerous buffet tables laden with decadent treats. But after a few weeks of indulgence, many people resolve to adopt a healthier diet starting on January 1.
And it turns out there are some diets that feature prominently in New Year’s resolutions.
INSIDER recently polled 1,102 people about their 2019 resolutions, and 473 respondents said theirs were related to eating healthier or dieting. When asked which type of diet they planned to adopt in the new year, the top five answers were a low-carb diet, calorie restriction, the keto diet, a low-fat diet, and eating less meat.
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Despite their popularity, however, these five eating strategies may have drawbacks.
INSIDER asked three registered dietitians whether or not the poll’s top five diets can really help people get healthier or lose weight in 2019. For almost every diet, their answer was the same: It depends.
Here’s a closer look at what the experts had to say about each of the five most popular diet resolutions.
1. Low-carb diet
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Carbohydrates, or carbs, have a bad reputation because they’re found in many foods that are both calorie-dense and nutrient-poor, like potato chips, baked goods, candy, and soda. Cutting back on those specific foods definitely can benefit health, registered dietitian Brigitte Zeitlin explained to INSIDER.
But it’s important to remember that plenty of healthy foods are high in carbs, too. Fruits, vegetables, whole grains, and beans are primarily made of carbohydrates but also come packed with health-promoting fiber and nutrients.
Because of this, diets that restrict all carbs – without making a distinction between cookies and clementines, for example – aren’t likely to make you healthier.
“What most people end up doing on low-carb diets is they remove a lot of the whole, plant-based foods that actually have health benefits and help lower your risk of certain diseases,” registered dietitian Andy Bellatti told INSIDER. “Avoiding fruit is not going to make you healthier, avoiding beans is not going to make you healthier, and avoiding oats is not going to make your healthier.”
A low-carb diet can also make workouts feel harder than normal, though this side effect will be more noticeable in people who are already active.
And when it comes to weight loss, there are still more caveats to note. First, weight loss on a low-carb diet may be short-lived.
“With low-carb dieting, most people see an initial reduction in water weight, so they see the scale drop the first week. I’ve seen people lose 10 pounds, even more,” registered dietitian Georgie Fear, author of “Lean Habits for Lifelong Weight Loss,” told INSIDER. “But after that, it slows down. Sometimes it slows to a crawl. [People] lose faith in the diet, they get tired of not eating their favorite foods, and then they go off. So most people will see the initial weight loss, but they’re not going to stick to it long enough to see lasting weight loss or lasting health benefits.”
It is possible for a low-carb diet to support lasting weight loss, as long as you’re swapping refined carbs for foods that are less calorie-dense.
“If somebody sticks to a lower carb diet and their weight is coming down, it’s typically not because the carbs themselves were doing anything sinister, but because their calorie intake is less,” Fear said.
2. Calorie restriction
For weight loss, cutting back on calories is “really the only thing that works,” Fear said. If you eat fewer calories than you expend – also known as creating a calorie deficit – you’ll lose weight.
Using a calorie-counting app is one way to track your intake, she added, but that requires a decent amount of work. You have to weigh and measure all the food you eat to ensure you get an accurate count. This approach may also lead to an intense, unhealthy focus on the number of calories you eat, Zeitlin said.
But there are some strategies that can help reduce your calorie intake without meticulous measuring or counting. Fear suggested tweaking the portions on your plate so that you eat more vegetables and fruits, which are naturally low in calories. If half your dinner plate is normally filled with rice and one quarter is filled with salad, try switching those proportions. You’ll be eating all of the same foods, but in amounts that help create a calorie deficit.
Next, try tuning into your body and eating only when you truly feel hungry.
“Many people are eating lots of calories because they’re bored, because they need a break from work, to soothe emotions or for various reasons other than hunger,” Fear said. “And those are calories your body is not asking for.”
And finally, consider skipping any high-calorie, low-nutrient foods that you don’t really love. For example: Treat yourself to a flaky croissant if that’s your absolute favorite pastry, but practice passing on the baked goods that are “just OK” for your taste buds, Fear said.
Both Bellatti and Zeitlin explained that if you’re simply trying to eat healthier, calorie restriction isn’t the best idea.
“[For an] overall healthy diet, focus on adding in more vegetables, more whole grains, more fish, more white-meat chicken, more fruits,” Zeitlin said. “We should be focusing on food, not numbers.”
Plus, calorie content isn’t the only quality that matters in a food.
“Compare snacking on pretzels or almonds,” Bellatti said. “The pretzels might have 20 fewer calories, but the almonds have so much more nutrition. They have vitamin E, they have more protein, more fiber, healthier fat. Lower-calorie doesn’t necessarily mean more health-promoting.”
3. Keto diet
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The ketogenic, or keto, diet calls for eating mostly fat with some protein and very few carbs. Generally, keto dieters limit carbs to less than 50 grams per day, and sometimes as low as 20. (For reference, a single slice of white bread has 14 grams of carbs; a large apple has 30.)
The diet gets its name from ketosis, the state your body enters when it starts burning fat for fuel instead of carbs. It was originally developed back in the 1920s as a way to treat the seizure disorder epilepsy, and it’s still sometimes used for that purpose. More recent adopters claim that the diet provides other benefits, like lower blood sugar and weight loss.
But none of the dietitians INSIDER interviewed recommended keto as a long-term weight loss strategy.
It might cause initial weight loss because it forces adherents to give up so many calorie-rich foods that are easy to overeat, Bellatti said. Zeitlin added that it can also cause the loss of water weight in the early stages, but that’s not actual fat loss.
Research on keto’s long-term effects is still lacking, but one study did find that, after a year, keto didn’t drastically outperform other weight-loss diets, according to the Harvard School of Public Health.
But can the keto diet improve your health outside of weight loss?
“If your goal is leveling up your health game overall, do not do the ketogenic diet. It’s excessively restrictive,” Zeitlin said. “Any diet that restricts your fruit and vegetable intake, I can’t get behind that.”
Bellatti agreed, noting that many of the foods keto limits, like starchy vegetables, fruits, and whole grains, provide healthy fiber and a feeling of fullness after you eat.
4. Low-fat diet
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Fats are not inherently bad for you. In fact, you need some fats in your diet. They provide energy and help you absorb certain nutrients. They’re used to build cell membranes and the coating that protects your nerves. They also play a major role in helping you feel full after you eat, Bellatti said.
But, as you’ve probably heard before, some types of fats are better for you than others. Many experts recommend limiting saturated fat (the kind prominent in red meat, full-fat dairy, and coconut oil) and replacing it with unsaturated fat (the type found in nuts, seeds, fish, avocados, olive oil, and more). There’s evidence that making this swap is linked with a lower risk of heart disease, according to the most recent Dietary Guidelines for Americans.
Fear explained that people who currently eat lots of cheese, red meat, ice cream, or other foods high in saturated fat could benefit their heart health if they reduce their portion sizes of these foods.
“You don’t necessarily have to cut it out, but just dial it back,” she said. “Instead of having the 8-ounce steak, maybe you can go for the six-ounce, or instead of putting a thick layer of butter on your toast, you could go for a thin scraping.”
Reducing your fat intake may help with weight loss, but only in the context of a calorie deficit. What you eat instead of fatty food matters.
“If instead if fat, you’re eating twice the amount of starch or sugar, it’s going to be a moot point,” Bellatti said.
Similarly, swapping equal amounts of unhealthy fats for healthy ones won’t spur weight loss.
“If you take out one tablespoon of butter and you put in one tablespoon of olive oil, that’s beneficial for your health, but it’s not going to help you lose weight, because the calories are the same,” Fear said.
Finally, Fear explained that while most people could comfortably reduce some of the fat in their diet without it negatively impacting their fullness, a dramatic reduction in fat intake could make you feel hungrier sooner after you eat. This could also hamper weight loss efforts.
“If you do reduce fat substantially, try and pay attention to when it’s making you too hungry after meals,” Fear said. “It’s just not going to end well because you’ll end up eating those calories back at dinner or snacking.”
5. Eating less meat
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All three dietitians said that limiting meat may help improve your health – it all depends on what you’re using as a replacement.
“There’s no harm in cutting down [on] meat as long as we’re replacing it with other high-quality proteins, like eggs, edamame, beans, chickpeas, lentils, almonds, or nut butter,” Zeitlin said. “We want to make sure we’re making up for it with the right stuff, not making up for it with more pizza.”
And if making these types of swaps result in a calorie deficit, you can lose weight, too. But Fear explained that eating less meat in and of itself won’t necessarily result in a change on the scale.
“I often find that people who strive to become vegetarian or vegan actually have a harder time losing weight, because when people avoid really rich sources of protein such as meat they actually find they need to eat more calories to feel satiated,” Fear said. “So I wouldn’t recommend this one as a weight loss strategy.
“But if somebody’s happy with their weight but maybe wants to do some good things for their cancer and heart disease risk, then decreasing the meat that they eat and substituting it with beans or other plant-based proteins can be a worthwhile venture,” she added.
SurveyMonkey Audience polls from a national sample balanced by census data of age and gender. Respondents are incentivized to complete surveys through charitable contributions. Generally speaking, digital polling tends to skew toward people with access to the internet. SurveyMonkey Audience doesn’t try to weight its sample based on race or income. Total 1,037 respondents, margin of error plus or minus +/- 3.15 percentage points with 95% confidence level.
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