The keto and no-carb diets are two popular ways of eating that involve restricting your carbohydrate intake. While they both limit carbs to varying degrees, the keto diet is more restrictive. The main difference between these diets is their carbohydrate intake. On a low-carb diet, you typically eat 50–150 grams of carbs per day, but on the keto diet, daily carb intake is restricted to fewer than 50 grams. Another main difference is protein intake. With low-carb diets, protein intake may be high, but with keto diets, protein intake should be moderate at around 20% of total calories. This is because excessive protein intake can prevent ketosis. Additionally, fat intake tends to be significantly higher on the keto diet, as fats replace carbs and protein.

Keto and No Carb Diet Differences

Macronutrient breakdown

Low-Carb Diet

Carbohydrates, proteins, and fats are known as macronutrients. They provide calories for the body and are needed in larger amounts than micronutrients, which are primarily vitamins and minerals.

There is no standard definition for a low-carb diet. However, it is generally defined as a diet that restricts carbohydrates to between 10% and 30% of total calories. This can be anywhere from 50 to 150 grams of carbohydrates per day.

A low-carb diet typically involves increasing protein and healthy fat intake, while reducing consumption of grains, sugar-filled foods, and starchy vegetables.

An example of a low-carb macronutrient breakdown is as follows:

• 10% to 30% of calories from carbohydrates
• 20% to 50% from protein
• 30% to 60% from fats

Keto Diet

The keto diet, short for ketogenic, is a very low-carb, high-fat diet. It involves getting 70% to 80% of daily calories from fat, 15% to 30% from protein, and no more than 10% from carbohydrates. This equates to less than 50 grams of carbohydrates per day, sometimes as low as 20 grams.

The keto diet aims to reach a state of nutritional ketosis, where the body uses fat as its main fuel source instead of carbohydrates. This is achieved by drastically reducing carbohydrate intake and increasing fat intake.

• 70% to 80% of calories from fat
• 15% to 30% from protein
• Up to 10% from carbohydrates

Weight loss

Both keto and low-carb diets are effective for weight loss. However, there are some differences in how they work and how quickly they produce results.

When you eat carbohydrates, your body releases insulin to take glucose to your cells for energy. Any leftover glucose is stored as fat. When you cut down on carbs, less insulin is released, and your body can enter fat-burning mode.

Low-Carb Diet

Low-carb diets typically allow for a wider range of carb intake, usually between 50 and 150 grams of carbs per day. This means that people following a low-carb diet can still eat some fruits, starchy vegetables, and beans. Low-carb diets tend to be less restrictive and easier to maintain over the long term. They are also less likely to produce quick results.

Keto Diet

Keto diets are more restrictive, limiting carb intake to fewer than 50 grams per day, sometimes as low as 20 grams. This restriction pushes the body into a metabolic state called ketosis, where it burns through available carbs and then starts breaking down fat for energy. Keto diets can spark quicker weight loss but may be challenging to stick to for extended periods.

While both diets can help with weight loss, the key difference is that keto diets are more restrictive and may lead to faster results, whereas low-carb diets offer more flexibility and are generally easier to maintain long-term.

Health benefits

The keto and no-carb diets are both popular ways of eating that involve restricting your carb intake. However, there are some key differences between the two, and each has its own set of health benefits.

• A low-carb diet can lead to weight loss and improved cardiovascular fitness.
• It can also result in lower blood sugar and insulin levels, which is beneficial for people with diabetes.
• Low-carb diets are less restrictive than keto diets, making them easier to follow and maintain over the long term.
• They eliminate many processed high-carb foods, which can be beneficial for overall health.
• They can be sustained long-term and have a less extreme adaptation phase than keto diets.
• Keto diets have been shown to help treat epilepsy, and may also impair the growth of certain types of cancer.
• They can lead to dramatic weight loss and improve most major risk factors for heart disease.
• Keto diets can help lower blood sugar and insulin levels, which is beneficial for people with type 2 diabetes.
• They can improve cholesterol and triglyceride levels.
• Keto diets can reduce appetite and hunger, making it easier to stick to the diet.
• They may improve insulin sensitivity.

In summary, both low-carb and keto diets can provide health benefits, but the keto diet is more restrictive and may be harder to follow long-term. It's important to consider your individual needs and health status when deciding which diet is right for you.

Side effects

Keto Diet

The keto diet is a very restrictive diet and may not be a practical long-term option for those looking to lose weight and improve their health. It can lead to the following side effects:

• Constipation due to low fibre intake
• Keto flu, which may include headaches, fatigue, brain fog, irritability, and lack of motivation
• Higher risk of kidney stones, osteoporosis, and gout
• Difficult to stick to for long periods
• May be too restrictive for most people

Low-Carb Diet

The low-carb diet is less restrictive and easier to follow than the keto diet. However, it may still lead to some side effects:

• Feeling weak
• Constipation
• May impact micronutrient intake
• May cause weight loss that is slower compared to keto

Sustainability

The keto diet is a popular, restrictive diet that limits carbohydrates and prioritises fat intake, with fat comprising up to 90% of daily calories. While it can be effective for short-term weight loss and managing certain medical conditions like epilepsy, it is not typically recommended as a sustainable long-term solution. The extreme reduction of carbohydrates can lead to nutritional deficiencies, and the high fat intake, particularly saturated fats, can increase the risk of heart disease and high cholesterol. The restrictive nature of the diet can also make it challenging to maintain, especially in social situations, and may lead to an unhealthy relationship with food.

On the other hand, a no-carb diet is an even more restrictive version of keto, eliminating almost all carbohydrates. While it can lead to rapid initial weight loss and may provide certain health benefits like improved heart health and blood sugar control, it is highly restrictive and likely unnecessary. The exclusion of carbohydrates can result in low energy levels and nutritional deficiencies, particularly of vitamins and minerals found in plant-based foods. The long-term health consequences of a no-carb diet are unclear, and it is not recommended for those with eating disorders, children, or pregnant or nursing individuals due to its restrictive nature and potential health risks.

In terms of sustainability, neither the keto nor the no-carb diet offers a balanced and maintainable approach to nutrition. While they may provide short-term benefits, they can be challenging to adhere to and may lead to potential health risks. A more balanced and sustainable approach would be to focus on a varied diet with a moderate intake of carbohydrates, proteins, and healthy fats, ensuring adequate nutrition and energy levels without the potential negative consequences of extreme restriction.

It is always advisable to consult with a healthcare professional before making any significant dietary changes, especially those as restrictive as keto and no-carb diets, to ensure they are safe and appropriate for your individual needs and circumstances.

Frequently asked questions