Atkins Diet: Does It Really Work?

Medically Reviewed by Zilpah Sheikh, MD on November 08, 2023
7 min read

The Atkins diet is an eating plan created by cardiologist Robert Atkins. It revolves around restricting carbs while eating mostly fat and protein. The idea is to burn body fat instead of carbs for energy, resulting in a shift in your metabolism.

Do bacon and eggs for breakfast, smoked salmon with cream cheese for lunch, and steak cooked in butter for dinner sound like a weight loss menu too good to be true? If you love foods like these and aren’t a fan of carrot-filled diets, the Atkins diet may be right for you.

You’ll have to learn how to limit your carbs on the Atkins diet, but you’ll enjoy plenty of tasty options instead.

You can lose weight on this eating plan, and you shouldn’t feel hungry or deprived. Today's Atkins diet focuses more on lean proteins, healthy fats, and high-fiber vegetables.

The Atkins diet focuses on proteins and fats like:

  • Meat
  • Poultry
  • Seafood
  • Eggs
  • Butter
  • Oils
  • Cheese

You’ll have to stay away from starchy and sugary carbs, including:

  • Bread
  • Pasta
  • Potatoes
  • Chips
  • Cookies
  • Candy

You’ll eat carbs in veggie form at first. As you progress, you’ll add in other foods, like beans/legumes, fruits, and whole grains.

A newer version of Atkins, called Atkins 40, has more relaxed rules and allows you to start with 40 grams of carbs in the daily diet. It doesn’t exclude any food groups at first, as Atkins 20 does.

There are limits to the amount of butter or fats that you should eat, but no strict guidelines for meats or other proteins.

There are four phases to the standard Atkins diet, also called Atkins 20.

Phase 1. This is when you help your body switch from burning carbs to fat. This process is called ketosis, and you should notice weight loss quickly. You’ll eat protein, fat, and only 20 grams of carbs in veggie form daily. Some people (like vegans) may start at the next phase.

Phase 2. You’ll add foods back to your diet, until you learn how many carbs you can eat while still losing weight.

Phase 3. Go to this level when you have about 10 pounds left to lose. You’ll learn how to maintain weight loss and lose the last few pounds.

Phase 4. You'll follow this for the rest of your life, to ensure that you don’t gain back what you’ve lost.

Atkins diet vs. keto

The Atkins diet and the ketogenic (keto) diet are similar. Both focus on eating fat while limiting carbs. On the keto diet, fat can make up 90% of your calories each day. On Atkins 20, it's up to 70%. Researchers aren't clear whether the keto diet is safe or will help you keep weight off in the long term. Doctors mostly suggest it to lessen the number of seizures in kids with epilepsy.

You won’t have to count calories, attend meetings, or buy special food on the Atkins diet. But it does mean big changes to the way you eat, especially if you’re used to starch on your plate or if you snack on chips, sweets, or other junk foods.

Limitations: You’ll have to cut out white flour, sugar, and other common carbs at first, and eat carbs only in vegetable form.

Cooking and Shopping: With the Atkins diet, it’s best to make meals from scratch. If you rely on prepared foods, read labels to find out how many carbs and how much sugar they have.

The foods you're allowed can sometimes come with added sugar or carbs, like lunchmeat and salad dressing. So check those labels too before you buy.

You can find Atkins-brand frozen foods, drinks, and snacks in stores, but you don’t need to eat them.

At restaurants, choose foods you’d eat at home. Ask the waiter about carb content and keep your hand out of the bread basket.

Exercise: You don’t need to exercise to lose weight with the Atkins diet, but you should get moving. Try to be active for 30 minutes or more every day. Talk to your doctor first if you've been inactive or have any medical problems.

Vegetarians and vegans: Atkins doesn’t require you to eat meat. Also, you'll skip the first phase of Atkins 20, which limits carbs too much.

Vegetarians get protein from:

  • Eggs
  • Cheese
  • Soy
  • Nuts
  • Seeds
  • Legumes
  • High-protein grains like quinoa

Vegans get protein from:

  • Legumes
  • Soy
  • Nuts
  • Seeds
  • High-protein grains like quinoa

Gluten-free diet: It’s easy to stick to that eating plan when you’re on Atkins. Foods with gluten are high in carbs. People on Atkins eat less gluten than people who eat the standard American diet.

Low-salt diet: There’s no need to add salt to any recipes for Atkins. Stay away from canned and packaged foods as much as you can, because they often have added sugars and other carbs, bad-for-you fats, and salt.

Pros: You may lose a lot of weight in the first couple of weeks on the Atkins diet, but their website says just 1-2 pounds is typical. It's also possible you'll avoid or reverse certain health conditions like diabetes, high blood pressure, and heart disease. But that's the case with many diets that lead to weight loss. 

Cons: If you've lost weight on the Atkins diet, as with most diets, you're likely to gain it back, research shows. Also, eating too much animal fat on this type of diet can raise your chances of heart disease and cancer. You may also feel some side effects from cutting carbs, such as:

  • Headache
  • Dizziness
  • Weakness
  • Extreme tiredness (fatigue)
  • Trouble pooping (constipation)

Cost: There are no membership fees, meetings to attend, or brand-name foods you need to buy for this diet. And there are free tools online and for your smartphone.

Support: You can follow Atkins by reading a book, but if you want extra support, the Atkins website has support groups and chat rooms, where you can talk to others who are losing weight the same way you are. There are also free recipes, meal trackers, and apps to make it simple to count carbs, plan meals, and shop.

Does it work?

The Atkins diet is one of the best-known low-carb diets, and the research shows it can work. If you fill your day with processed carbs like white bread, pasta, and white potatoes, and you don’t eat many fruits and veggies, then this diet may be the jump-start you need to lose weight.

You can quit your usual go-to foods and start with the Atkins food list. The initial phase in the Atkins 20 plan is limited in food choices but focused on protein, fat, and vegetables that are low carb and not starchy. In each phase, you add back food groups: first nuts, seeds, and berries; then fruits, starchy vegetables, beans, and whole grains. With the Atkins 40 plan, you can choose from a larger variety of foods and carbs but still little to no starchy foods.

With Atkins 20, the closer you get to your weight loss goal, the more variety of foods you’re allowed. Ideally, you’ll stick to their healthy list and not go back to your old ways.

If you like variety in the foods you eat, the Atkins 40 plan would likely be better for you. Of course you'll still need to keep your portion sizes under control, which may be easier as a low-carb diet can help tame hunger. 

Is it good for certain conditions?

When you’re overweight, shedding pounds can improve your health, and we know the Atkins diet works. But it’s still unclear how the higher amounts of animal protein and fat in the diet affect long-term health.

Recent research suggests that people on the Atkins diet who chose foods rich in plant fat and protein did better with their health than those who went with the diet rich in animal fat and protein.

This makes sense to me, and the Atkins 20 and Atkins 40 diets reflect this idea. They focus more on getting fat and protein from heart-healthy choices like olive oil and protein like soy and lentils.

If you have diabetes, heart disease, kidney disease, or high cholesterol, talk to your doctor before starting this diet to make sure the balance of carbs, fat, and protein is right for you. 

The final word

For the person who needs structure in their diet, limiting starchy, sugary carbs will help cut calories and allow for weight loss. And focusing on proteins and fats that are plant-based is the healthy and smart thing to do.

For your long-term health, you have to move on from the initial Atkins 20 diet. It’s the later phases of the diet, especially the Atkins 40, that give you the variety of foods that are important for health. You have to exercise and keep portions small while you start eating nuts, seeds, beans, fruits, starchy vegetables, and whole grains again.

Is the Atkins diet healthy?

According to information on the Atkins website, the diet is healthy if you're looking to lose weight, gain energy, lower your blood pressure, and improve other health problems. But if you're not careful, you may miss out on essential vitamins and minerals found in carbs like fruits and vegetables. Be sure to include healthy carbs and fats in your diet while avoiding processed meats and other foods.

How long is it safe to stay on the Atkins diet?

The Atkins diet has four phases, and the last phase is "lifetime maintenance." This means you've reached your goal weight, but will stick with the Atkins eating plan for the rest of your life. Some experts are concerned about the possible long-term effects of the Atkins diet, like a higher chance of heart disease and cancer.