Top 21: Atkins Diet

The Atkins diet is based on carbohydrate restriction, which forces the body to use stored fat for energy. It’s not simply that you can’t eat much carbohydrate, but that you must not consume too much at once in order to avoid flooding the body with glucose, which results in fat production and storage.

At each meal, you should eat 4 to 6 ounces of protein. You’ll also be allowed one serving of fat at each meal, such as butter, salad dressing or olive oil. Fill the rest of your plate with low-carb vegetables, such as spinach, bell pepper, cucumber and tomato.

Atkins Diet Four-Phase Plan:

Phase 1: Induction

You’re allowed 20 grams of net carbs daily on the traditional Atkins 20 plan. Net carbs are calculated by subtracting fiber and sugar alcohols from the carbohydrate in grams. For example, if something contains 15 grams of carbs and 5 grams of fiber, the net carbs are 10.

Of the 20 grams, 12 to 15 grams should come from nonstarchy vegetables or “foundation vegetables,” such as arugula, cherry tomatoes and Brussels sprouts. Besides vegetables, you’ll mainly eat meat, poultry, seafood, cheese, eggs and oil or butter at every meal.

This phase only lasts two weeks, depending on your weight loss goals.

Phase 2: Balancing Your Diet

At the start of the second phase, you'll eat 25 grams of net carbs daily, then gradually increase your overall carb intake by 5 grams until you find your personal carb balance, ranging from 30 to 80 daily grams of net carbs. This will add more carbs to your Atkins diet food list, such as vegetables, berries, nuts and seeds.

You stay in the balancing phase until you’re within 10 pounds of your goal weight.

Phase 3: Maintaining Your Weight After Dieting

You’ll continue to increase your carb intake in 5 to 10 gram increments to include more fruits, starchy vegetables and whole grains until you’ve reached your goal weight. By the end of this phase, you'll likely consume 80 to 100 grams of net carbs daily.

You'll stay in phase 3 until you've reached your goal weight and maintained it for a month.

Phase 4: Lifetime Maintenance

Most people maintain an intake of 40 to 120 grams of net carbohydrates daily for the rest of their lives to maintain their lost weight. If you want to continue using Atkins, consider Atkins 100, a plan recommended for those who want to maintain their current weight. It allows 100 grams of net carbs daily.

Keep in mind that a food low in net carbs doesn’t always mean it’s a healthy choice to keep your weight in check. The idea of net carbs “seems mostly to be used as a way to sell highly-processed foods full of synthetic ingredients to low-carb dieters," says Monica Reinagel, a licensed nutritionist, host of the Nutrition Diva podcast and co-founder of the Weighless program. "A candy-like bar loaded up with fiber and sugar alcohols doesn't sound like much of a treat to me, but it also doesn't sound like much of a meal.”

Yes, you can lose weight on Atkins. Whether you’ll be able to keep it off is another question altogether.

Short-Term Weight Loss

In short-term studies, weight loss and a decrease in body fat – while preserving lean muscle – are generally reported on the ketogenic diet, which is similar to Atkins in many respects.

Because of this, it is not uncommon for Atkins dieters to report a loss of 6 to 15 pounds in the first two weeks. However, this does not represent fat loss. Instead, initial weight loss is usually water weight.

In many studies, this weight loss is greater than the loss on a standard low-calorie diet in the first six months. This is especially true in the first week or two when it is not unusual to drop several pounds rapidly.

• In a 2017 study, 90% of the participants on a ketogenic diet lost 5% of their body weight, while only 29% in the control group achieved the same (1). 

• Evidence shows that ketogenic and low-carb diets may suppress appetite. One study found participants lost an average of 13% of initial weight by following a very low-calorie diet that induced ketosis for eight weeks, then two weeks of food reintroduction. In this case, participants reported being less hungry, and their hunger hormone levels reflected that feeling  (2).

• A review of more than 120 studies and 21,942 participants, found that low-carbohydrate diets resulted in an average weight loss of 10.19 pounds after six months. For comparison, the low-fat diets brought about an average loss of 9.61 pounds. The highest average weight loss was attributed to the Atkins diet – about 12 pounds. However, after one year, overall weight loss pretty much disappeared for all participants, regardless of diet (3).

Long-Term Weight Loss

“The Atkins diet, just like any diet, is not sustainable for the long term. While you may lose weight in the short term, the vast majority of people who lose weight with diets will gain it back through no fault of their own, because the human body is wired for survival,” explains Alissa Rumsey, a nutrition therapist based in New York City and the author of “Unapologetic Eating.” “This type of yo-yo dieting – or weight cycling – is more detrimental to your health than staying at a higher weight,” Rumsey says.

Research supports the idea that protein increases feelings of fullness, and being in ketosis changes hormone levels related to appetite. "A diet that is low enough in carbohydrates to put you into ketosis may, in fact, suppress your appetite, even though you are reducing your calorie intake,” Reinagel says.

However, she adds, “Unfortunately, as soon as you exit ketosis, the effect is reversed. And that may be why these diets tend to be very effective at producing rapid weight loss – but not as good at promoting lasting weight loss.”

Weight Maintenance and Management

Only the most devoted people can stick to a diet that provides no more than 120 grams of carbohydrates daily for the rest of their lives. After all, a single slice of pizza contains around 35 grams, while a piece of a birthday cake will set you back about 75 grams.

According to the National Weight Control Registry, of more than 2,600 people who maintained at least a 30-pound weight loss for one year or longer, less than 1% did so on the Atkins diet or a similar plan. Instead, most successful weight loss maintainers were on a high-carbohydrate, low-fat diet (5).

To start Atkins 20, the central Atkins program that allows 20 grams of net carbs daily during phase one, you’ll likely need to clean your cupboard and hit the grocery store or your local butcher.

Here are tips for beginners:

• Stock up on fish, beef, chicken and other proteins. Eat one 4- to 6-ounce serving at each meal.

• Add a serving of fat to each meal. Butter, salad dressing and olive oil are fair game.

• Round out your meals with leafy greens and other low-carb vegetables.

• Stock the kitchen with lean proteins and non-starchy vegetables. 

• Start looking at nutrition labels, paying particular attention to carbohydrates, fiber and sugar grams. 

• Begin to take a high-quality vitamin and mineral supplement.

• Choose an exercise regimen that you can stick with. 

• Aim for at least eight glasses of water each day.

For more guidance, check out the Atkins lifestyle book “Atkins: Eat Right, Not Less." You can also buy books from "The New Atkins for a New You" series, which includes a guide and cookbook

It is likely that you won’t notice much of a difference in your total food expenditures. While it is true that meat and fresh vegetables – mainstays of the Atkins plan – are pricier than most processed and fast foods, how much you'll spend will depend primarily on your choices of protein sources. Are you mainly buying ground beef or springing for veal? Chicken or turkey? Chuck or New York strip? Choosing the less expensive protein options and buying vegetables in season should keep the grocery tab reasonable.

You do not have to purchase any special food products to follow the Atkins diet, although Atkins-branded snacks, frozen meals and shakes are available if you choose to buy them.

No, overall, the Atkins diet is not easy to follow. In general, diets that severely limit entire food groups for a long time tend to have lower success rates than less-restrictive diets do, and the Atkins diet is the definition of a restrictive diet. It ranks No. 19 in Easiest Diets to Follow.

The Atkins diet isn’t known for its convenience. At home, building variety into meals is a little harder than usual. Eating out also takes more effort. Alcohol is limited. Company-branded food products and online resources may be helpful if you’re struggling to stay on track. In 2013, Atkins launched a frozen-food line.

Atkins provides meal plans, recipes with ingredient lists and food carb counts, all in a print-friendly format. There is a smattering of recipes across various cuisines, from American to Middle Eastern to French to Asian.

The Atkins diet is not the right option for those with certain medical conditions. It's important to consult your doctor before beginning a diet plan, especially one that eliminates many foods.

• Anyone with kidney disease or a history of kidney stones should avoid a high-protein or ketogenic diet such as the Atkins plan.

• Pregnant women should go directly to the phase four long-term maintenance stage.

• Adolescents and people with diabetes or prediabetes should consult their doctors before starting this or any other diet plan.

• Individuals with decreased bone density or diagnosed with osteoporosis should avoid this plan. 

• Athletes need carbohydrates for energy, so this diet style is not recommended for especially active people.

Rumsey cautions that “going on a restrictive diet like Atkin's diet can cause disordered eating behaviors, such as feeling anxious and out of control around food, opting out of social functions for fear of what food will be there, increased food cravings and binge eating.”