Keto and Atkins are two of the most popular low-carb diets available today.
While many people believe that they are the same weight-loss diet, they are not.
There are similarities between Atkins and keto, but there are also some very distinct differences.
For example, many people doing keto will stay at 20-net carbs for the majority of the weight-loss phase, while Atkins encourages you to discover your own personal carbohydrate tolerance instead.
On Atkins induction, however, which covers the first two weeks of Atkins 20, you will be eating similarly to how those on keto eat for the entire weight loss phase.
Many who create their own low-carb diet tend to call what they’re doing keto, because they are using the state of ketosis to carve off the pounds, but there is actually a couple of different low-carb programs called the keto diet, as well.
What is the Keto Diet?
Keto is a shortened form for the term “ketosis.”
The Keto Diet is a specific diet created by Dr. Stephen Phinney, but sometimes it’s used to refer to any ketogenic diet.
A ketogenic diet is one that puts you into the state of ketosis.
Ketosis is a metabolic state that occurs when glycogen, the storage form of carbohydrates, runs so low that the body has to turn to alternative fuel sources to keep the brain alive and prevent your blood sugar from dropping too low.
These additional fuel sources, include:
- alternative sources of glucose
- certain amino acids
- body fat
For those who want to lose weight, without a lot of effort, hunger, and cravings, the state of ketosis can help you achieve that goal.
Most people lose their excess hunger and cravings for carby foods and sugar within a few days after entering the state of nutritional ketosis, making it easier to eat at a calorie deficit.
The theory behind the keto diet is quite simple:
Cut down on the amount of carbohydrates you eat on a daily basis, so that the body has to use its glycogen stores, and it will have to turn to burning fat when that glycogen runs too low.
Clearing Up a Keto Diet Misunderstanding
The most popular keto diet today was created by Dr. Stephen Phinney for endurance athletes and physicians who were interested in treating their overweight and obese patients using a low-carb diet.
However, when those who had stalled using a low-carb diet showed interest in his dietary approach and began using a ketone blood meter to check and see if they were in the optimal ketosis range that Dr. Phinney recommends, 1 to 3 mmol/L, many low-carb dieters discovered that they were not in ketosis at all!
This resulted in a massive movement within the low-carb community to lower protein consumption and raise dietary fats in order to hit the recommended target for ketosis.
But many dieters took this generic advice to the opposite extreme, going too low in protein and too high in fats. This caused many dieters to gain weight instead of lose.
The keto diet is a low-carb, high-fat diet. Stats that are often quoted online are:
- 15 percent protein
- 5 percent carbs, or less
- 80 percent fat
While this “high-fat” formula is accurate, as far as percentages go, it is also greatly misunderstood.
According to Dr. Phinney, the person who coined the term “Nutritional Ketosis,” the only reason why he labeled his diet a low-carb high-fat diet is because part of that 80-percent fat comes from your body fat!
It doesn’t come from your diet unless you are already at maintenance.
The Real Keto Diet
The real Keto Diet consists of:
- 20- to 45-net carbs (depending on which Phase you’re in)
- 15 to 25 percent of your “maintenance” calories in protein
- just enough dietary fat to meet your weight-loss goals
Both Dr. Phinney’s version of keto and the ketogenic diet over at the Reddit forums use fat to dial in your calorie deficit, so on paper, if you keep track of your protein, carb, and fat grams, it will look like you’re eating too much protein.
This is because the greater majority of that fat percentage is coming from your body fat!
Most ketogenic dieters stick to 20-net carbs for most of the weight-loss phase, and then either increase carbs a bit when they approach maintenance or increase dietary fat to raise their calories.
However, there is nothing wrong with upping your carbs a bit higher than 20-net carbs.
In fact, the average low-carb diet contains about 35-net carbs. This gives you plenty of carbs for vegetables, salads, a few extras, and even a treat now and then.
What is the Atkins Diet?
Atkins is not just one single diet.
Today, there are several Atkins diets that you can choose from, depending on your age, health condition, and weight-loss goals.
These diets are called Atkins 20, Atkins 40, and Atkins 100.
Atkins 20 is the classic Atkins plan and marketed to be the original Atkins diet. It is not the original 1972 plan, however.
Atkins 20 is said to be similar to the 2002 version of the Atkins diet, but it’s not that either. It aligns with The New Atkins for a New You, written by Dr. Eric Westman along with Dr. Phinney.
This is due to its recommendations on vegetables, fats, and proteins, which we’ll talk about in just a minute.
Atkins 20 is designed for those who have:
- more than 40 pounds to lose
- a 35-inch waist, or more, for women
- a 40-inch waist, or more, for men
- prediabetes (insulin resistance) or diabetes
This diet begins at 20-net carbs for the first two weeks, and allows you to choose from a list of foundation vegetables, salad fixings, and other very low-carb foods.
This is the most restrictive phase of the diet and is similar to the Keto Diet because it is ketogenic.
It quickly puts you into the state of ketosis within one to three days, which switches your metabolism from predominantly burning glucose to one that predominantly burns fats instead.
At the end of this Induction period, you can choose to either return carbs to your diet, very slowly, in 5-net carb increments, following a specific order, or you can stay at 20-net carbs for a little bit longer.
Atkins has particular qualifications for being able to stay on Induction for longer than two weeks.
The order of what’s known as the Carbohydrate Ladder, returns food categories to your diet, such as:
- nuts and seeds
- fresh cheeses
- low-glycemic fruits
- and even alcohol
Recommendation is that you return foods one at a time, so you can see how your body reacts to each food.
Phase 2 of Atkins 20 may, or may not, be ketogenic, depending on how high your carbohydrate tolerance is.
Many dieters prefer to stay within the keto definition of less than 50-net carbs per day during the weight-loss phase, in order to control cravings and excessive hunger.
Atkins 40 is for those who do not have severe insulin resistance.
It works beautifully for those who are only mildly resistant.
It starts you out at 40-net carbs, instead of 20, and doesn’t restrict categories.
You’re allowed to pick from any acceptable food category, but must evenly space your carbohydrate intake throughout the day.
This is done by limiting the carbs you eat at each meal to 10 carbs, or less. You also get two snacks which are limited to 5 grams of carbohydrates each.
The spacing works to keep your body storing enough insulin to handle the extra carbohydrate load at your meals and snacks, but if you’re more than just mildly insulin resistant, eating that often can prevent weight loss.
Atkins 40 is designed for those who:
- have over 40 pounds to lose
- are only mildly insulin resistant
- are looking for greater variety in your diet
- are willing to settle for slower weight loss in exchange for more carbs
- are pregnant or breastfeeding
On Atkins 40, there is no Induction period. You simply jump right in with the Atkins Diet you’ll be following for life.
Atkins 100 was introduced in the latest Atkins book, Eat Right, Not Less, by Colette Heimowitz, spokesperson for Atkins Nutritionals, Inc.
This latest plan is for those who want to follow a lower-carb program for health or weight loss.
This plan is for those who are not insulin resistant at all.
Foods are limited to the same list as for those doing Atkins 40, but instead of sticking to just 40-net carbs per day, you limit yourself to 100-net carbs.
Since you are not insulin resistant, you can choose whether to evenly space out your carbs or just cut back to that level of intake.
For that reason, this diet works well with the Paleo Diet or for those who just want to move to a whole foods diet and avoid heavily refined foods like sugar, starches, and other unnecessary carbs.
Keto Vs. Atkins: What You Can Eat
The biggest differences between keto and Atkins depends on which Atkins plan you’re following.
Atkins 20 will be similar to what you eat on Keto, unless your carb allowance offers room for extra goodies like low-carb products or an occasional drink with dinner.
Those doing keto at the Reddit forums, take the stance that anything that fits into your macros is allowed.
They have no restrictions on what you can or cannot eat because they also count calories.
On more traditional forms of keto, however, you don’t count calories.
Same with Atkins, neither of the three Atkins plans requires you to count your calories, but you can if you need to. It’s just not required.
When not keeping a tight rein on your macros, you do need to be more careful with your food choices and portions, so this is why Atkins 40 is based on portion control.
The recommendation for Atkins 40 is to try and keep to portions of 5 to 10 carbs, with only occasionally going as high as 15 grams of carbs in a single meal.
This allows you to keep your 12- to 15-net carb vegetable allowance for the day without it being a struggle.
You don’t want to skip your vegetables and just eat starchy foods, or it might backfire on you.
If you have mild insulin resistance, eating too many carbs or starchy foods can make the condition worse.
Meats, Eggs, and Cheese
Protein foods are very important on all of these low-carb diets, but protein can also be confusing because the older Atkins books don’t limit protein, while today’s Atkins Diet does.
Most keto diets also limit protein to some degree.
While pasture-raised animals are thought to be best, there is no qualification on what type of meat, eggs, or cheese you eat except that cheese should be full-fat varieties on Atkins.
Typical recommendation is 0.8 grams of protein per pound of lean body mass that you have.
This works out to about 15 to 20 percent of your maintenance calories, which might be an easier way to figure it out.
Protein is a goal, so you don’t really want to eat much less than that because you need it to repair damaged or worn out cells and supply a bit of gluconeogenesis, if needed.
All three Atkins diets come with protein restrictions of 4 to 6 ounces of protein per meal.
Eggs equal 1 ounce of meat or cheese.
There is no restriction on snacks, but snacks are said to be about half of what you’d need for a meal, or less.
Eat only what you need to tide yourself over until you officially eat again.
Snacks on Atkins should not be full-sized meals, especially if you’re eating protein-packed snacks.
Along with an adequate amount of protein, you also need to eat enough healthy fat for cellular regeneration and repair.
Every cell uses fats as part of its structure, so focus on what’s known as “good” fats like olive oil, coconut oil, real butter, avocados, nuts, and cold-pressed nut oils.
On all versions of the keto diet, one uses fat to dial in calories.
Fat is NOT a goal!
Since protein is a set amount and carbs are eaten to your tolerance, fat calories are the only macro that you can use to control your calories.
In the older Atkins books, fat came with no restrictions, but today, the newer Atkins versions all recommend you limit added fats to 2 to 4 tablespoons per day.
Most of the fat you eat should be coming from your meat, eggs, and cheeses.
Vegetables and Salads
Both Keto and Atkins use vegetables and leafy salads as the basis for your diet.
On Keto, however, vegetables are held to a very tight rein and are not required at all. Atkins takes a firmer stance on how much you should eat every day.
Use vegetables and salad to help bring variety to your meals, but only if you like them.
Vegetables and salad are not required because Keto advocates would rather you choose foods you like so you’re more willing to stick with your low-carb plan.
All versions of the modern-day Atkins program require you to eat 12- to 15-net carbs worth of vegetables and salad fixings per day. Older versions do not require you to eat that much.
In 1972, only 2 cups of salad was allowed per day, and no cooked vegetables until you reached the upper levels of the diet.
In 1992, 2/3’s cup of cooked vegetables were added to that 2-cup salad because many of Dr. Atkins patients admitted to cheating on the diet that way.
In 2002, cooked vegetables were raised again to 1 cup of cooked vegetables and a 2-cup salad per day.
Low-Carb Products and Condiments
Most low-carb products did not hit the shelves until after Dr. Atkins died, but he did talk about their approach in interviews.
In Dr. Atkins professional opinion, these products were being designed to help those in pre-maintenance and maintenance to live more normal lives. The weight-loss phase was designed to be a meat and vegetable diet.
Those doing keto today come pretty close to that, especially those who stay with 20-net carbs.
However, for those who skip the vegetables, you’ll often see them chowing down on low-carb tortillas, flatbreads, and wraps to make lunches easier.
Not all keto dieters do this, of course, but plenty of them do.
Since the Reddit folks keep a close eye on calories, they do use an occasional low-carb product like pastas, breads, and mixes, but the 20-net carbs they mostly stick to helps them from overeating low-carb products and condiments.
Those doing Dr. Phinney’s version of Keto tend to be fairly health conscious, so products are rare and most of their 20-gram allotment is spent on vegetables and condiments.
Today, Atkins Nutritionals has a line of Atkins products that they advocate are safe for those doing Atkins.
However, they are not as pushy as some people believe they are. While a lot of their ads are your typical marketing advice, if you’re not losing weight and ask Collette for some personal advice, she will tell you to skip the products and just do Atkins using whole foods instead.
Sugar Substitutes and Alternatives
No matter which low-carb diet you choose, you’re going to have to give up sugar, honey, and pure maple syrup. Natural sweeteners are not allowed.
Accepts all sugar substitutes and alternatives.
There are no restrictions.
Allowed to use up to 3 servings a day of sugar substitutes.
This fact is not well known, and the first thing Atkins Nutritionals will address if you’re not losing weight on a standard Atkins diet.
The restriction of 3 servings includes what’s found in low-carb products, especially their own shakes and bars.
It’s not just the sugar alternative that you use in your morning coffee and baked goods that is limited.
Higher Carb Foods
Many higher carb foods are not allowed on traditional low-carb diets.
The thought behind the restriction has to do with their place on the glycemic index.
However, the glycemic index numbers were obtained by using healthy individuals and not those with insulin resistance or even diabetes.
This makes the index essentially worthless.
However, some keto dieters and those doing Atkins 40 and Atkins 100 do use some of the following foods, which has not affected their weight loss or ability to manage their weight after achieving goal.
Keto comes with no restrictions, but higher carbs or calorie items, such as:
- peanut butter
- mixed vegetables
- winter squash
- peas and carrots
- sugar-free syrups
- almond flour
- coconut flour
These need to be used with care if you are insulin resistant or have diabetes.
Try adding only one food at a time, so you can see how your body handles these types of foods.
Atkins 40 and Atkins 100 allows higher carb foods in appropriate amounts. Some of these foods include:
- peanuts and peanut butter
- whole milk and buttermilk
- traditional beans
- soybeans and soy flour
- split peas
- all fruits
- winter squash
- peas and carrots
- white or sweet potatoes
- corn, cornmeal, cornflour
- brown rice
- whole wheat pasta
- whole wheat breads
- sugar-free syrups
- sugar-free ice cream
However, for Atkins 40, you are cautioned to add these foods only in small portions, about 5 to 10 grams of carbohydrates per serving.
Once you enter the pre-maintenance phase, you can then increase the portion size.
Atkins 20 and Atkins 40 both come with the potential to be ketogenic, which makes them very similar to keto, but the difference in food choices and portion sizes make them very different.
While a traditional keto diet doesn’t allow whole grains, high-glycemic fruits, or root vegetables, Atkins 40 seeks to introduce healthier food choices right from the very first day.
This allows you to be able to create a diet that you can use even after you reach maintenance.
One of the most difficult aspects of a weight-loss diet is the different way you eat after reaching goal weight.
The newer versions of Atkins attempt to eliminate the problem by having you create a personalized version of Atkins during the weight loss phase.
Instead of changing what you eat at maintenance, you coast into maintenance already knowing how you’re going to eat.
Dr. Phinney’s version of keto does something very similar.
You begin at a very low carbohydrate intake, which increases as you move into Phase 2. But by pre-maintenance, you will have already found which carbohydrate foods are best for you.
Instead of adding more carbohydrates, as you do for Atkins 20, you increase your dietary fat calories to match your activity level.
Both methods work very well.