Atkins 100™ Diet Facts

Understanding the Atkins 20 Diet in full is important before beginning. Find out how many carbs you can eat on a low carb diet & more.

Q: Is Atkins 100 a ketogenic Diet?

Most individuals can maintain a fat burning metabolism when carbs are at the 50 gram level or less. Ketones are simply the by-product of fat burning. The body will switch to its back up fuel system of fat burning when carbs are low enough. A healthy active young athlete may be able to maintain fat burning at the 100 level, but most overweight individuals will need to be at the 50g level.

Q: What is the Atkins Diet?

The Atkins Diet is the original leading low-carb lifestyle plan that provides quick, effective, satisfying and balanced weight management based on an extensive body of scientific research. The Atkins Diet is designed to “flip the body’s metabolic switch” from burning carbs to burning fat. Graduated carb introduction limits blood sugar and insulin spikes, which cause hunger and cravings, and result in overeating and weight gain.


  • Atkins has the additional application of being a lifestyle for the millions of people who know that eating fewer carbohydrates keeps them feeling healthy. With Atkins 100, you are able to consume 100 grams of Net Carbs per day, meaning more variety while still experiencing the positive benefits of reducing your carb intake.
  • On Atkins 100 you will eat:
    • More vegetables than the USDA recommends
    • Proteins including meats, fish, poultry and plant-based proteins
    • Healthy fats including olive oil, avocado and nuts
    • Dairy including whole Greek yogurt, as well as hard and soft cheeses
    • Variety of fruits and whole grains

Q: Does this mean people can consume a little sugar and still lose weight?

We do not recommend consumption of added sugar on Atkins 100, as it has an immediate impact on blood sugar and offers little nutritional benefit compared to other foods allowed in the daily 100g Net Carb intake.

Q: How is this different than the Phase Four of the Atkins plan?

With Atkins 100, you’ll eat 100 grams of Net Grams of carbohydrates a day. It’s that simple! Here’s what else you do:


  • You eat a minimum of 12 to 15 grams of Net Carbs a day of Foundation Vegetables.
  • You eat three 4- to 6-ounce servings of protein a day.
  • You eat two to four servings of added fat a day.


You budget the remaining 85 grams of Net Carbs from the entire carbohydrate Acceptable Food list provided for phase 1 through 4 from the Atkins carb ladders.


With Atkins Phase Four you stay at the level of carb tolerance you discovered by going through the phases which could be anywhere from 40 to 100 grams of carbs daily depending on the individual and their tolerance to carb intake.

Q: What data did you use to determine the efficacy?

We evaluated 38 published papers that reduced carbohydrate intake to levels consistent with Atkins 100 and concluded that a low-carb diet of 100g Net Carbs per day can, help to keep weight-off, and may improves other health markers such as triglyceride, HDL, glucose and insulin levels.

Q: Will I still be able to lose weight quickly?

100g Net Carbs has been scientifically validated as an acceptable level of carbohydrate restriction help prevent weight gain for healthy individuals. The young and healthy may be able to lose weight at this level, others will need a lower level of carb intake to achieve weight loss. It depends on an individual’s carbohydrate tolerance.

Q: Are any foods still off-limits?

Anyone using a low carb diet to improve their health should continue to avoid/limit added sugar and refined carbs such as white flour, which are low in nutritional value. In addition, dieters should avoid foods that act as “triggers” for them, personally (i.e. foods that cause unhealthy cravings and temptations). Keep in mind the acceptable food list is a guideline to start you on your journey toward making smart, healthy choices.

Q: I’ve been following Atkins 20 or Atkins 40 – should I switch to Atkins 100?

There are some things to consider before you jump to Atkins 100.

Reasons to continue following Atkins 20:

  • You have more than 40 pounds to lose
  • You are pre-diabetic or diabetic
  • Your waist circumference is higher than 40 inches for men, 35 inches for women
  • You are content with food choices being re-introduced gradually, in pre-defined order
  • You are seeing positive results with Atkins 20 (“If it isn’t broke, don’t fix it!”)


Reasons to consider following Atkins 40:

  • You have more than 20 but less than 40 pounds to lose
  • You are pre-diabetic or diabetic
  • Your waist circumference is less than 40 inches for men, 35 inches for women
  • You are  nursing and want gradual weight loss
  • You are currently on Atkins 20, and looking for more variety in food choices


Reasons to consider moving to Atkins 100:

  • You have reached your weight loss goals and are looking for a healthy lifestyle approach.
  • You are very active but would still like to experience the benefits of reducing your carbohydrate intake
  • You want to start by making small, smart changes
  • You are not pre-diabetic or diabetic
  • Your waist circumference is less than 40 inches for men, 35 inches for women
  • You are pregnant or nursing

Q: How do I get back on track after an “indiscretion”?

First of all, don’t beat yourself up. We all have moments of weakness, and maybe that plate of French fries your friend was eating was more than you could resist. Second, don’t play the game of “Well, since I’ve already messed up, I might as well go whole hog.” For the rest of the day, eat appropriately. Don’t wait until tomorrow to get back on the wagon.

Q: How can individuals following Atkins 100 ensure they are getting a fully balanced, nutritional diet?

  • A well–constructed Atkins 100 lifestyle program is founded on the principles of optimal protein intake, adequate healthy fat intake, and reduced carbohydrate consumption. If you follow those general principles and choose the most nutrient dense options of carbohydrate you can achieve a fully balanced nutritional diet.  Individuals experience success on Atkins by restricting carbohydrates to a level that promotes the burning of fat for fuel and reduces blood sugar spikes.
  • The scientific evidence for the Atkins low carbohydrate program continues to build and evolve in the past two decades. Results reported in independent peer review journals have consistently demonstrated robust health outcomes and better weight management.
  • The Atkins Diet includes a wide variety of foods throughout the entire plan and encourages the consumption of a healthy balance of nutrient dense food, adequate protein, a full array of high-fiber vegetables, low glycemic fruits, whole grains, and healthy fats. It teaches every individual to discover their own perfect carbohydrate balance.

Q: Can vegetarians or vegans follow the Atkins Diet?

The Atkins Diet allows individuals to consume a wide variety of foods, all framed within a context of eating fewer carbohydrates and sugars. The diet can be followed as a vegetarian or vegan. Atkins 100 is actually a great option for a vegetarian or vegan. Vegetarians will can get their protein from eggs, legumes, nuts, dairy, and soy products. Vegans can get sufficient protein from seeds, nuts, soy products, soy and rice cheeses, seitan, legumes and high protein grains like quinoa.

Q: What are some of the health benefits associated with the Atkins Lifestyle?

Independent third-party clinical research has found that the Atkins Lifestyle reduces risk factors for heart-disease, insulin resistance, diabetes, and improves markers of inflammation.


By eating carbohydrates in moderation, the Atkins Lifestyle helps individuals (even those without diabetes) maintain stable blood sugar levels, leading to fewer carb cravings and more energy, among other health benefits. Scientific research has consistently found that subjects at a high risk for Coronary Artery Disease (CAD) that were following the low-carb approach had improvements in their cholesterol profiles, decreasing their risk of developing CAD.


There are also many digestive benefits that come with following Atkins. Fiber requirements can be easily met because the Atkins Lifestyle replaces highly refined, low-fiber carbohydrates with lots of vegetables, legumes, low-sugar fruit, nuts, seeds and whole grains. The diet includes high fiber carbohydrates to replace processed foods, which increases fiber intake. A high-fiber diet is the best way to lower risk factors associated with the colon. Additionally, numerous scientific studies have confirmed that those eating a high-fiber diet have lower cholesterol levels and fewer incidences of heart disease than those on a low-fiber diet.


With its ability to help individuals reach weight management goals, improve lipid profile and blood pressure, increase energy and reduce risk of heart disease, diabetes and many other life-threatening conditions, the Atkins Lifestyle is indeed a healthier, more balanced way of eating and living.

Q: It is common knowledge that Atkins limits carb intake, but does the diet allow for individuals to eat any carbs?

The Atkins lifestyle includes nutrient dense carbohydrates at every level, including Atkins 20 and 40. Those following the Atkins 100 plan are encouraged to choose foods from the acceptable food lists which incorporates a wider variety of carbohydrate choices in a more generous portion size such as starchy vegetables, legumes, and whole grains. Atkins offers a well-balanced way of eating that incorporates foods from all major food groups – it does not include high sugar items like cakes or candy.

Q: Isn’t Atkins criticized for having too much fat?

Atkins does focus on fat, but a balance of fats that are commonly agreed to be healthy, such as monounsaturated fats like olive oil and avocado as well as naturally occurring saturated fats and polyunsaturated fats. If they wish, although not necessary, individuals can easily avoid saturated fats while on Atkins by following the plan as a vegetarian. It is important to remember that if carbohydrate levels are low, fat intake needs to be higher.


Research from peer-reviewed independent studies has consistently demonstrated the diet’s safety and efficacy at the levels of fat intake recommended on a lower carb lifestyle.

Q: What is “Carbohydrate Intolerance” and Metabolic Syndrome?

Atkins offers a scientifically proven plan that delivers increased weight loss and health marker improvements among those who have carb intolerance. Only a doctor can make a medical diagnosis of carb intolerance, but there is a simple way to spot the first indicator: waist measurement. Fat deposited at the waist is a particularly unhealthy type of fat (visceral fat), and increased amounts of visceral fat can be indicative of carb intolerance. Women with waist sizes greater than 35 inches and men with waist size greater than 40 inches should consider speaking with their doctors about carb intolerance. It is important to note that this is a simple guideline and health risks can vary with height and body type. The clinical signs include high triglycerides, low HDL, potentially higher blood pressure, and insulin resistance.

Q: I'm used to counting calories. How many am I allowed on the Atkins Diet?

The Atkins Nutritional Approach counts grams of carbohydrates instead of calories. However for weight loss purposes we suggest you shoot for a healthy range. For women that range is approximately 1500 to 1800 calories. For men that range is approximately 1800 to 2200 calories per day. Be sure to limit empty calories and follow the acceptable foods list.


Research has shown that on a controlled carbohydrate program, more calories are burned than on a low-fat, high-carbohydrate diet, so there is a certain metabolic advantage to the controlled carb approach. But understand that this does not give you a license to gorge.


The real goal of the Atkins lifestyle is to learn eating habits that will enable you to permanently maintain a healthy weight and lifestyle. This includes changing old habits such as overeating that contributed to your original weight problem.

Q: What is carb creep and how can I avoid it?

The great thing with Atkins 100 is that you have a wider variety of food choices to pick from with a slightly more generous serving size, including starchy vegetables and whole grains so you don’t feel deprived. However, you want to be sure you’re keeping portion sizes in check in order to remain in the range of Atkins 100  On the website, we’ve provided a list of 5g and 10g net carb serving sizes of many of your favorite foods so you know what is appropriate.

Q: What is the highest level of carbohydrate consumption per day recommended for Lifetime Maintenance?

The important concept to understand in order to maintain your weight is finding your personal carb balance. You should find the highest level that won’t allow you to regain weight or cause hunger and cravings. Each person has a personal carb balance, and a bit of trial and error may be required for you to find yours.

Q: Can I drink alcohol now following Atkins 100?

The body burns alcohol for fuel when alcohol is available. So when it is burning alcohol, your body will not burn fat. This does not stop weight loss; it simply postpones it. Since the alcohol does not get stored as glycogen, you immediately get back into fat burning after the alcohol is used up. If it does not contribute to weight gain, an occasional glass of wine is acceptable, so long as you count the carbohydrates in your daily tally. (A 3 1/2-ounce glass of wine contains about 4.3 grams of carbohydrate.) Spirits such as Scotch, rye, vodka and gin are acceptable, but do not mix with juice, tonic water or non-diet soda, all of which contain sugar. Seltzer, diet tonic and diet soda mixers are permitted. If you have added alcohol to your regimen and suddenly stop losing weight, discontinue your alcohol intake.

Q: What types of products and support does Atkins offer?

Atkins provides a wide variety of products, tools and support. The New Atkins for a New You and New Atkins Made Easy books provides readers with guidelines on how to follow the original Atkins four phase approach. A cookbook hit the stands in 2011 and is entitled The New Atkins for a New You Cookbook: 200 Simple and Delicious Low-Carb Recipes in 30 Minutes or Less.


The most up to date book by Colette Heimowitz is Atkins Eat Right Not Less which reflects changes to the diet, how to use Atkins 100, and the new research and the science supporting it. You may purchase the book & cookbook at local retailers such as Wal-Mart and Target. You can also find these books online.


Atkins also offers a variety of frozen meals, nutrition bars and shakes which can serve as a convenient meal, snack, or treat. Some of these products are indulgently sweet but low in carbs – so Atkins dieters can indulge their sweet tooth while managing hunger all day. They can be purchased at major retail stores or at Additionally, Atkins offers a free online community and resource center at with more than 1,600 recipes and menu plans, as well as shopping lists for each phase of the plan. Community Members get all the resources and support to complete the diet online for FREE at – other diets can cost upwards of $30 per month. Upon registration, a quick-start kit is available for FREE on to give dieters all the information they need to get started.

Q: Where do I find Articles/Data regarding the Atkins Diet?

To find more information regarding articles or data supporting the Atkins Diet, please visit our SCIENCE and LIBRARY tabs. If you’re looking for information to share with your physician, please direct them to our Healthcare Professional Portal,