Atkins Diet vs the Carnivore Diet

Dr. Robert Atkins was a pioneer in the low carbohydrate movement. He advocated for a ketogenic diet long before keto became recognized as a viable, healthy diet.

However, the Atkins Diet and the Carnivore Diet are not the same. And it’s more similar to popular ketogenic diets than it is to the Carnivore Diet (interestingly, most Carnivores come from a Ketogenic Diet).

Let’s look at some similarities, differences, and reasons why a Carnivore Diet may be the final solution to a revolutionary diet pioneered by Dr. Atkins.

What is Atkins Diet?

The Atkins Diet is a high fat, low carbohydrate diet that is broken into 4 Phases.

Phase 1: Induction

During induction you are limited to 20g of carbohydrates per day. Atkins recommends these carbs come from salad greens and veggies. This initial phase lasts at least 14 days, in which you eat meat, fish, eggs and added fats from butter, mayonnaise, and vegetable oils.

No fruit, bread, pasta, grains or starch vegetables allowed.

You must track the 20g of carbohydrates carefully. But besides carbs you can eat until satisfied.

Atkins recommends a host of supplements during this Phase as well as all the following phases. He “ok’s” sweeteners like sucralose and saccharin. But recommends avoiding caffeine like tea, coffee, and soft drinks as they may promote hypoglycemia and sugar cravings.

Phase 2: Ongoing Weight Loss (OWL)

In this next phase you can add 5g of carbohydrates per day until you reach your “Critical Carbohydrate Level for Losing” (CCLL). This is the number of carbohydrates at which you stop losing weight.

During this time you can add in seeds and nuts, berries and fruits, starchy vegetables and whole grains and even wine and other spirits.

Phase 3: Pre-maintenance

This third phase adds additional flexibility to the diet in preparing you for a lifetime of Atkins. You can add up to 10g of carbs per week. You can add these carbs evenly distributed across days, or in bigger “treat” meals.

Phase 4: Lifetime Maintenance

This final phase is just about honing in on your personal diet, what amount of carbs work for you to achieve your ideal body long term, and how to make it work in various circumstances.

Atkins Diet vs the Carnivore Diet

In the Atkins Diet no food groups are eliminated (besides junk). While he recommends avoiding refined carbohydrates, you can eat fruit, vegetables, grains, nuts, seeds, and dairy. Plenty of fiber on this diet. It’s all about finding your “carb number” and tracking that daily, and then eating proteins and fat to satiety.

While there are some similarities, the Carnivore Diet is quite different.

Similarities

The similarities in the diet are largely based on their macronutrient breakdowns. And it’s these macronutrient ratios that switch you from a “glucose-based metabolism” towards a “fat-based metabolism.” The foods and methods in which this is accomplished, however, is quite different.

#1: Carbohydrates

Both Atkins and Carnivore are low carbohydrate diets. Yet, in this similarity is one of the big differences – Atkins has daily allowances for carbohydrates from various sources while Carnivore doesn’t. Besides the carbohydrates found in the meat and organs of animals, all other carbohydrate sources are off limits on Carnivore.

The limitation of carbs in the diet provide a benefit derived both from Atkins and Carnivore – beating sugar/carb addictions as well as the maladies associated with high carb diets (insulin resistance, hyerinsulinemia and associated disease).

#2 Ketosis

Neither Atkins or Carnivore are strictly ketogenic diets. There is no measuring ketones, and no tracking macronutrient ratios of fat:protein.

Yet, both diets result in varying degrees of ketosis as a consequence of their protocols. Whether following Atkins or the Carnivore Diet you switch to a “fat-based” metabolism.

#3 Common Side Effects

Largely a result of carbohydrate restriction and a fat-based metabolism, both of these diets free you from hunger where you eat until you are satisfied. There is no calorie counting besides the carbohydrates in Atkins Diet.

On both diets people tend to beat addictions, enhance energy, feel better and improve health.

Differences

While they share some commonalities, there are striking differences in the diets.

#1: Primary Purpose

The unseen, but perhaps the biggest difference, is the primary purpose of the diets.

The Atkins Diet is first-and-foremost a fat loss diet. The health ramifications are seen as a consequence of losing fat via controlling carbohydrates.

The Carnivore Diet is first-and-foremost a health diet. The driving force behind eating only meat is to get healthy. And “healthy” means something different for everyone. It could be eradicating an autoimmune disorder, patching up a leaky gut, or fixing metabolic dysfunction. Fat loss is often a consequence of getting healthy. But some people gain weight initially on the Carnivore Diet, and that’s ok.

Not ok with Atkins though.

#2: Food Choices

With Atkins you can eat an unlimited quantity of vegetable oils, you can eat fruit, grains, nuts, seeds, and other foods as long as they fit into your CCLL number – your daily carbohydrate allowance.

With Carnivore eating there is no counting carbs and there is no eating from food groups that aren’t animal-based. No plant-based foods allowed.

#3: Meal Timing

Atkins recommends eating 3-5 meals/day and never going more than 6 hours without eating.

Carnivore is a more intuitive approach to diet and appetite.

“Eat when hungry.”

Most Carnivores eat just 2 meals a day, and many just once per day. There is no time limit. If you aren’t hungry don’t eat; if you are, eat.

Intermittent fasting is often a natural consequence of the Carnivore Diet. You find yourself going long periods of time without being hungry. No need to force a fast. And definitely no need to prepare 5 meals a day.

#4: Supplements

Atkins diet mandates supplements. In the program it isn’t clear whether he believes this is out of necessity or a way to optimize health.

In the Carnivore Diet no supplements are necessary. Carnivores will often supplement with electrolytes, especially when transitioning into the diet, and some may take other supplements to try and “optimize” (for example, you might take a Vitamin D3 supplement if you are indoors 24/7 and this is likely a good idea) though none are required.

#5 Simplicity

Atkins diet, while not rocket science, requires tracking, monitoring, and measuring. There are 4 Phases. Supplements. Meal timing.

Like many diets, it can overtake your life. It becomes all consuming.

Thoughts about food make up the majority of your thoughts everyday.

“When is my next meal?” 

“Can I eat this?”

“How many carbs do I have left?”

“How many carbs are in this?”

And on and on and on…

The Carnivore Diet is beautifully simple.

“Eat meat. Drink water.”

Yes, from this simplicity many questions and concerns can arise.  But these mainly stem from misconceptions (like: “don’t I need fiber” and “what about vitamin C?”)

Once the first 30 days are behind you the diet is a cinch.

You don’t even think about it anymore.

Atkins vs the Carnivore Diet – My Concerns

Atkins Concern

If you choose to follow Atkins diet, I think you are following a diet that is healthier than 99% of diets out there. Although I disagree with many of the “allowed” carbohydrate, plant-based foods, the fact they they are restricted to such low levels means the relative harm from them are dramatically diminished.

For example, I don’t think anyone should ever eat soy, but if you are only allowed to eat 50g of carbs/day the amount of soy one might actually eat is quite negligible, and a healthy digestive tract can likely handle the offenders (like lectins for example).

My biggest problem with Atkins Diet is the vegetable oils and added fats. First it’s easy for people to overdue it on these. So if fat loss is there goal, these can easily cause a problem.

But perhaps more importantly is the ease in which these fats are oxidized and the impact of a diet super high in omega-6 fatty acids that overwhelm omega-3s.

If you think of each of your cells as a house and that house is built with fats, the kinds of fats you eat is of paramount importance. Fats that are easily damaged result in the building of houses (cells) that dysfunction. Dysfunctional, easily damaged cells drive disease.

Carnivore Concern

One concern many people have about Carnivore is the restricted nature of the diet.

Only meat.

Atkins allows much greater flexibility, which people believe makes it easier to follow. I believe the opposite is true.

One person’s “flexibility” is another person’s relapse.

I’ve known many people that have followed Atkins Diet and I don’t know any that have maintained it. This is not exclusive to Atkins, but with all diets. However, the problem with flexibility is temptation and addiction.

With the “Induction Phase” of Atkins and the Carnivore Diet in general, these addictions can be beat. But by reintroducing the wrong carbs and fats on the Atkins Diet, temptations and addiction can re-surface.

If you’d like to learn more about how to structure a meat-based / carnivore diet and what plant foods could be ok to eat, I’d highly recommend watching the Meat Health Masterclass: