Is Atkins Considered Keto? The Key Differences Explained

December 5, 2025 •

3 min read

While both Atkins and keto are prominent low-carb diets, a common misconception is that they are identical. The critical distinction lies in their approach to carbohydrate intake, particularly after the initial phase, where Atkins allows for a gradual reintroduction of carbs. This fundamental difference means Atkins is not strictly considered keto, despite their initial overlap.

Quick Summary

This article explores the similarities and critical differences between the Atkins and ketogenic diets. It examines their varying approaches to carbohydrate consumption, macronutrient ratios, and the sustainability of ketosis, helping readers differentiate between the two popular low-carb eating plans.

Key Points

Initial Overlap: The Atkins diet's initial 'Induction' phase is functionally ketogenic, with a carb limit similar to the keto diet's sustained restriction.
Phased Approach: Atkins is a four-phased plan that gradually reintroduces carbs, moving away from the continuous state of ketosis.
Long-term Ketosis: The standard keto diet requires continuous, very low carbohydrate intake to remain in ketosis, unlike Atkins.
Macronutrient Differences: Keto emphasizes higher fat consumption, while Atkins allows for higher protein, particularly in later phases.
Sustainability vs. Intensity: Atkins is often considered more sustainable long-term due to its increasing carb allowance, while keto is more restrictive.
Not Identical: Because Atkins has an 'exit strategy' from strict carb restriction, it is not accurately described as a keto diet in its entirety.

The ketogenic and Atkins diets are two of the most well-known and followed low-carbohydrate eating plans. While they both restrict carbs, they are not the same. Understanding their core differences is essential for anyone considering adopting either plan, primarily the progressive nature of Atkins compared to the consistently strict carb limit of the standard ketogenic diet.

The Core Principles: Keto vs. Atkins

The Ketogenic (Keto) Diet

The classic ketogenic diet is a high-fat, moderate-protein, and very low-carb diet aimed at maintaining a constant state of ketosis. This requires limiting net carbs to typically 20–50 grams per day. Exceeding this limit can stop the body from burning fat for fuel.

The Atkins Diet

The Atkins diet is a four-phased plan that starts with a low-carb phase similar to keto, but then gradually increases carbohydrate intake. This approach helps individuals find their personal carb tolerance. Due to this increase, Atkins is not intended to maintain perpetual ketosis, unlike the standard keto diet.

A Closer Look at the Phases

Atkins Phases: A Journey, Not a Destination

Atkins' structured phases include:

Phase 1 (Induction): Limits net carbs to around 20 grams daily to start weight loss and initiate ketosis, similar to keto.
Phase 2 (Balancing): Gradually increases carbs, adding more nuts, seeds, and berries.
Phase 3 (Pre-Maintenance): Allows more variety, including some starchy vegetables and fruits.
Phase 4 (Lifetime Maintenance): A permanent lifestyle with a broader food range as long as weight is stable, where most people are out of ketosis.

Keto's Consistent Approach

The standard keto diet lacks progressive phases. Rules remain consistent to maintain ketosis through constant carb monitoring.

Comparison: Atkins vs. Keto

Here's a comparison outlining key differences:


Feature	Ketogenic (Keto) Diet	Atkins Diet
Carb Intake	Consistently very low (typically 20-50g net carbs per day).	Starts very low (~20g net carbs) but increases through progressive phases.
Ketosis Goal	Continuous nutritional ketosis is the main objective.	Ketosis is a feature of the initial phase, not a long-term goal.
Macronutrient Ratio	High fat, moderate protein, very low carb.	Higher protein is allowed, especially in later phases. Moderate fat.
Sustainability	Can be difficult to maintain long-term due to strict carb limits.	Designed for long-term maintenance by reintroducing a wider variety of foods.
Food Variety	More restrictive, eliminating many fruits, grains, and starches.	Becomes less restrictive over time, allowing for more food types.

Why is Atkins not strictly considered keto?

Atkins is not strictly keto because its later phases involve significantly higher carbohydrate intake than required for nutritional ketosis. While the initial phase can induce ketosis, the entire Atkins plan does not maintain it. Keto is defined by the constant, low carb intake needed for sustained ketosis, which Atkins moves away from. Modified Atkins diets (MAD) exist for continuous ketosis in clinical settings, showing that the standard Atkins requires modification to be consistently ketogenic. Atkins includes a structured exit from deep ketosis, while keto does not.

Conclusion

While both Atkins and keto are effective low-carb diets, their phased structure (Atkins) versus consistent low-carb approach for continuous ketosis (keto) makes them distinct. The choice depends on your goals and preferred dietary structure.

For further reading, consult authoritative sources on dietary science:

The National Institutes of Health (NIH) provides research on ketogenic diets.

A Quick Guide to Carb Intake

Atkins Induction: ~20g net carbs, similar to keto.
Atkins Maintenance: Up to 80-100g net carbs, above typical keto limits.
Standard Keto: 20-50g net carbs, requires consistent restriction.

Your Keto and Atkins Journey

Consulting a healthcare provider is recommended before starting a new diet. Choosing between Atkins and keto involves considering a phased approach versus continuous ketosis. Both can aid weight management and metabolic health, but their structures determine if Atkins is considered keto. It can be ketogenic initially, but the overall diet is not.

Final Thoughts on Diet Choice

Atkins suits those seeking a structured plan with increasing carb flexibility. Keto is for those committed to continuous ketosis through strict, constant low-carb rules. Focusing on whole foods and listening to your body are key to success in either approach.

Frequently Asked Questions

The main difference is the duration of strict carb restriction. Keto is designed to keep you in a continuous state of ketosis, while Atkins uses a phased approach that reintroduces carbohydrates over time, eventually moving you out of continuous ketosis.

Yes, during the first 'Induction' phase of the Atkins diet, your carbohydrate intake is restricted enough to put your body into a state of ketosis. As you move through the subsequent phases and increase your carb intake, you will likely exit ketosis.

The standard ketogenic diet is generally considered more restrictive than the Atkins diet. Keto requires consistently very low carbohydrate intake to maintain ketosis indefinitely, whereas Atkins gradually increases allowable carbs, offering more dietary flexibility in later stages.

No. While both are low-carb, keto is characteristically high-fat and moderate-protein. Atkins allows for a higher protein intake, particularly as you progress through the phases, and is not as focused on maximizing fat consumption.

The best diet depends on the individual's goals and ability to adhere to the plan. Atkins is specifically designed with a maintenance phase for long-term weight management and can be easier to stick with due to less restriction over time. However, some find the constant rules of keto easier to follow.

The standard Atkins diet is not suitable for long-term ketosis, as its phased approach reintroduces carbs. For continuous ketosis, a strict keto diet is necessary. Some clinical modifications of the Atkins diet exist for specific therapeutic purposes that require sustained ketosis.

Many people find the Atkins diet more sustainable because it allows for a wider variety of foods as you progress, which can make it feel less restrictive and easier to maintain over a longer period. In contrast, the constant strictness of keto can be challenging for some.