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By Melissa Matthews
There's no denying that people are really into the low-carbohydrate, high-fat ketogenic diet. In fact, you've probably already been lectured about the benefits of going keto from cubicle mates, cousins, or that annoying guy at the gym.
With all the keto talk going around, you have noticed that it sounds a lot like another low-carb diet out there: Atkins. On the surface, the two diets seem pretty similar, since they both emphasize eating more fat and reducing carbs. But there are actually some very big differences between the two diets.
We talked to various medical professionals to help sort out the nuances of each diet.
The idea of the ketogenic diet is to get into ketosis, which is when your body uses fat instead of carbohydrates for energy. In this state, fat travels to the liver and makes byproducts called ketones; these enter your bloodstream, and are converted into energy. Many people measure ketones using at-home testing kits to determine whether or not they're in ketosis.
In order to enter ketosis, most of your calories (about 75 to 85 percent) need to come from fat, says Jenny Kramer, R.D. at Indiana University Health. Roughly 10 to 15 percent of your calories should come from protein, and 5 to 10 percent should come from carbs.
This emphasis on fat is why people frequently eat large amounts of bacon, butter and cream on the keto diet. However, most nutritionists say it's better to eat healthier fat sources like avocados, nuts and seeds, and eggs.
Put simply, the Atkins Diet is all about following a low-carb eating plan. There are various versions of the Atkins Diet, depending on how much weight you want to lose.
The most extreme version, the classic Atkins 20 Diet, is broken into four stages. Each level allows for more carbs and food choices than the previous stage. As you lose weight, you move onto the next stage, gradually increasing carbs. This plan restricts certain foods, including legumes, fruits and yogurt, during various stages.
The Atkins 40 plan is more flexible, doesn't have tiered stages, or restrict foods.
People with more pounds to drop may choose the classic Atkins plan that limits carbs to 25 grams per day; the more flexible plan allow for 40 carbs per day.
Although Keto doesn't necessarily ban carb-y foods like bananas or bread, they're pretty much a no-go. Even foods like vanilla yogurt could knock you out of ketosis: one six-ounce serving has 24 grams of carbohydrates.
According to Liz Weinandy, R.D. at Ohio State University, many keto dieters tend to eat more saturated fats, like cheese and butter, rather than heart-healthy monounsaturated fat sources, such as avocados.
"The people I see are usually using a lot of butter, a ton of coconut oil, a lot of whipped cream," she explains to MensHealth.com.
A healthier keto diet might include steak with steamed broccoli, since it's lower in carbs, and lots of butter.
The initial stage of the classic Atkins Diet is extremely restrictive: only nuts, seeds, cheese, fats, proteins and specific low-carb vegetables are allowed. Legumes, fruits, whole grains, starchy vegetables, cottage cheese and yogurt are forbidden. However, as you progress through each stage, more carbs and food choices are added until you're allowed to eat whatever you're want–provided you stay under 100 grams of carbs.
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The Atkins 40 offers more flexibility because no foods are restricted if they fit within the 40 grams of carbs limit.
Keto is more restrictive.
Atkins offers more flexibility, according to Kramer. "The Atkins diet probably doesn’t have quite as much restriction you may have more access to different carbohydrates. Even at the highest phase you’re probably still not someone who is eating breads and pastas, but you would have more room for fruits at that point," she says.
Maintaining ketosis is extremely difficult because nearly everything has carbs. Nuts? Yup! Same goes for avocados, yogurt, and other high-fat foods you might not associate with carbs. Plus, you'll need to weigh foods to make sure you're eating appropriate serving sizes to maintain the ratio of fat, protein and carbs.
The classic plan gets more flexible as you lose weight, so you don't have to say goodbye to carbs forever. Plus, dieters don't have to worry about getting in 80 percent of their calories from fat, which can be hard for many people, says Weinandy.
According to Weinandy, maintaining ketosis is extremely hard. Typically, people eat too protein and not enough fat to maintain the fat-burning state. As proof, she says that most "keto" dieters aren't even following the diet–despite their best intentions. Instead, their diets are more similar to Atkins in practice.
"A ketogenic diet is not just eat all the meat you want to," says Weinandy. "I think that’s really lost on a lot of people."
Weinandy cautions against going high-fat for weight loss. "The risks for a pretty healthy person usually outweigh the benefits," she says. Weinandy believes it should only be used for certain patients, like those with refractory epilepsy who may experience fewer seizures on the diet.
So what are the risks? Long-term, you could lose out on water soluble vitamins, like vitamins B and C. Not to mention that many people on Keto often have higher cholesterol and fat levels after several months, she says.
"In general, most diets you can safely follow for two to three months," she explains.
Atkins allows for a wider range of food, so dieters can eat more healthy foods like fruit. Thus far, there is no conclusive study showing whether Atkins is safe long-term. However, Weinandy points to recent research that showed extreme eating plans, both high carb and high fat diets, are linked to shorter lifespans.
Neither is necessarily great for your overall health, says Weinandy. She believes that a good, healthy diet wouldn't restrict any food groups. Fruit, which is loaded with antioxidants and fiber, is generally avoided in both diets.
If you are drawn to a lower carb plan, Weinandy recommends something similar to the South Beach diet, which balances complex carbs, lean protein and healthy fats.
According to Konstantinos Spaniolas, Associate Director of the Stony Brook Metabolic and Bariatric Weight Loss Center in New York, people will successfully lose weight on keto. That's because in addition to burning stored fat for energy, people often have fewer cravings and eat less calories on keto.
"They can stick to a relatively lower caloric intake because of the reduced cravings," he previously explained to MensHealth.com. Some people claim to have lost hundreds of pounds on the Keto Diet.
Similar to the Ketogenic Diet, Atkins will help with short-term weight loss. In a review, dietitians and doctors at U.S. News & World Report said the diet's claims of dropping up to 15 pounds in two weeks is legitimate. However, the diet may not be sustainable for everyone, and weight can creep back.
The verdict: Tie; both diets have been shown to help people lose weight. However, neither are shown to offer long-term results.
A diet that restricts major food groups, like whole grains and fruit, is unsustainable and unhealthy, according to our experts.
If you do want to drop a few pounds, she recommends working with a professional dietitian or enrolling in weight management classes. These will help you change unhealthy behaviors and provide support while you lose weight. Other easy fixes include no after dinner snacks, cutting out packaged foods and increasing exercise.
So while keto may be all the buzz right now, it may not be the best, or healthiest, diet for you. "People do not have to go on ketogenic to lose weight," says Weinandy. "There are better ways to lose weight."