12 Popular Low-Carb Diets, and Their Pros and Cons
Different Types of Low-Carb Diets: What You Should Know
When it comes to cutting carbs, there are various approaches. Before attempting any of these diets, here’s what you need to understand.
Eggs, berries, cheese, and avocado are considered low-carb foods.
A low-carb diet is not simply a low-carb diet; it can have different names and forms. The diet has gained popularity for its claimed benefits in weight loss and health improvement. Most Americans consume over 200 grams (g) of carbohydrates daily, so reducing carb intake would be considered a lower-carb approach, according to nutrition consultant Kelly Schmidt, RD, LDN from Columbus, Ohio.
The Mayo Clinic recommends that carbohydrates should make up 45 to 65 percent of an individual’s daily caloric intake. In a 2,000-calorie diet, this equates to 900 to 1,300 calories or 225 to 325 g of carbs per day.
The low-carb trend continues to grow, and some studies indicate short-term weight loss benefits. However, researchers caution against its long-term safety. One study found that individuals who consumed the lowest amount of carbs had a higher risk of cardiovascular disease, stroke, and cancer-related mortality.
Considering these findings, it is important to carefully consider a low-carb diet. If you decide to pursue one, be aware that there are different types available, such as the ketogenic diet and the Dukan diet. However, the name alone is not the most critical factor. Nutrition expert Kelly Schmidt emphasizes the importance of focusing on eating real food, which contributes to the success of low-carb diets.
It’s worth noting that many of the popular low-carb diets lack scientific research, and their claimed benefits may only be based on individual experiences. With these limitations in mind, let’s explore 12 well-known low-carb plans and how they function.
1. A Simple Low-Carb Diet
According to Schmidt, there is no official definition for a low-carb diet. Generally, consuming around 50 to 100 grams of carbs per day is considered a basic low-carb approach. However, the key is to eat fewer carbs than you normally would. This plan allows for personalization based on your body’s needs and lets you choose which carb sources to include (such as fruits, vegetables, dairy, whole grains, nuts, legumes, and seeds). Unlike restrictive plans, it doesn’t dictate what and when to eat, offering more flexibility. It suits individuals who prefer freedom and dislike tracking carb grams.
Following this conventional plan may have its advantages. In one study, obese adults with metabolic syndrome (a cluster of risk factors linked to cardiovascular disease and type 2 diabetes) were assigned to low-, moderate-, or high-carbohydrate diets for four weeks. The low-carb group experienced improvements in their triglyceride levels, “good” HDL cholesterol, and measures of their “bad” LDL cholesterol, regardless of weight loss.
2. The Ketogenic, or ‘Keto,’ Diet
The ketogenic diet is an extremely strict low-carb diet that restricts daily carbohydrate intake to around 50 grams, with some experts suggesting even lower limits of 30 or 20 grams. This diet emphasizes consuming a high amount of fat, which can make up to 80 percent of your overall diet. Franziska Spritzler, RD, CDCES, a low-carb dietitian based in Hollywood, Florida, recommends most individuals to stay under 30 grams of carbs, but active people can consume slightly more.
By following a keto diet, your body’s primary energy source shifts from carbs to fat. This change can lead to rapid initial weight loss, which can be highly motivating. However, the diet’s major drawback is its restrictive nature, as it primarily consists of fat sources, limited protein, and non-starchy vegetables. It is challenging to sustain and is typically intended for short-term use rather than long-term adoption.
A research review found that keto diets result in slightly greater weight loss compared to low-fat diets, with an average difference of about 4.4 pounds. However, these results are not likely to be maintained over time. The study showed that after approximately five months, individuals on the keto diet tend to regain the weight they initially lost.
3. A Modified Low-Carb Diet with Higher Fat Intake
This plan is similar to the keto diet, but it allows for a higher carbohydrate intake, preventing your body from entering a state of ketosis as it does during keto. Instead, you consume more carbohydrates, making up around 25 percent of your calorie intake, while fat makes up over 60 percent. Researchers argue that this approach, with a more practical carbohydrate allowance of 100 to 150 grams per day, is easier for many people to follow compared to the strictness of the keto diet. Although low-carb, high-fat diets aid in weight loss, the long-term health effects remain unknown, requiring further research.
Some individuals adopt this low-carb diet to enhance their performance during workouts. Advocates claim that it trains the body to utilize fat as an energy source, providing sustained endurance for prolonged exercise sessions. However, a study suggests that the impact of this diet on performance is still uncertain. If you’re an athlete interested in this eating style, it’s recommended to consult a registered dietitian specializing in sports nutrition to determine what suits you best.
4. The Atkins Diet
The Atkins diet was the pioneer of the low-carb trend. Dr. Atkins observed the significant effects of reducing carb intake while allowing unlimited protein and fat, influencing appetite and insulin levels. The plan starts with a very-low, ketogenic-like approach and gradually reintroduces carbohydrates from sources like vegetables and fruits. It’s crucial to avoid the mistake of adding back too many carbs, leading to weight gain and the misconception that the diet is ineffective. The diet includes prepackaged foods and snacks, often processed regardless of being labeled “low carb.” To maximize its benefits, it is recommended to prioritize whole foods. In terms of effectiveness compared to other diets, Atkins showed promising results, with participants losing around 22 pounds in six months based on a meta-analysis.
5. Modified Atkins and Modified Keto Diet
A modified Atkins diet involves consuming 10% of calories from carbohydrates, 30% from protein, and 60% from fat. While primarily studied for treating epilepsy, some individuals are adopting this “moderate” approach for weight loss. The term “keto” refers to being in a state of ketosis, but achieving this may not be possible with only 10% carbs for many people. For those aiming for ketosis, it is advisable to consult a registered dietitian to ensure the appropriate macronutrient ratio or monitor blood ketone levels.
6. Low-Carb Paleo
The low-carb version of the paleo diet focuses on consuming fat and protein while minimizing carbohydrates. However, eliminating grains, legumes, beans, sweets, and dairy alone does not guarantee a low-carb diet, as starchy vegetables and fruits can still contribute to carb intake. According to Spritzler, a paleo diet can vary in carb content, ranging from keto levels to normal carb levels. One advantage of this eating plan is its emphasis on whole, unprocessed foods. However, individuals who prefer a more plant-based diet may find it heavily centered around meat. To maintain a low-carb approach, it is advisable to choose vegetables with naturally lower carb content such as cucumbers, tomatoes, zucchini, and peppers.
There is a lack of comprehensive studies on the overall effectiveness of the paleo diet, particularly in its low-carb form. Nevertheless, some studies suggest that a paleo diet may aid in weight loss, reducing belly fat, as well as lowering blood pressure and lipid levels. Researchers note that the downside lies in the short-term and low-quality nature of existing trials evaluating the diet. Additionally, the paleo diet tends to be 10 percent more expensive than a regular diet and may increase the risk of calcium deficiency.
7. Whole30
Whole30 is a program that emphasizes dietary changes rather than being solely focused on low-carb consumption. During a period of 30 days, participants are instructed to consume only meat, seafood, vegetables, fruits, and fats, while avoiding all forms of added sugar, including alcohol, grains, legumes, and dairy.
For individuals accustomed to the standard American diet, which typically lacks sufficient fruits and vegetables while containing excessive amounts of added sugar and fat, Whole30 may represent a drastic approach. It could potentially aid in weight loss, as mentioned by Spritzler. However, due to its allowance of unlimited carb intake, it may not be suitable for individuals with type 2 diabetes. Since this program is intended as a temporary challenge, it requires careful consideration of one’s commitment and planning for post-30-day dietary choices.
8. The Low-Carb Mediterranean Diet
According to Spritzler, the Low-Carb Mediterranean Diet combines the advantages of both a Mediterranean diet and a low-carb diet, making it an ideal choice for overall health. Studies have demonstrated that following a Mediterranean eating pattern is linked to a reduced risk of developing cardiovascular disease and mortality.
What sets this diet apart from other low-carb diets is the emphasis on replacing saturated fats with unsaturated fats. This is particularly beneficial for individuals with type 2 diabetes, who are more susceptible to heart disease. Instead of consuming butter, cheese, and cream, the primary sources of fat in this diet consist of olive oil, fatty fish, nuts, seeds, and avocado.
The significant advantage of this diet is its heart-friendly nature. However, some people may be drawn to low-carb diets due to the appeal of indulging in highly palatable foods such as bacon and cheese. Research suggests that for individuals with diabetes, it is recommended to limit carbohydrate intake to no more than 50 percent of daily calories while obtaining at least 30 percent of calories from fat. Prioritizing vegetables and whole grains as sources of carbohydrates is also advised.
9. Dukan Diet
The Dukan Diet consists of four phases: focusing on high-protein foods, gradually adding vegetables and carb-containing foods, allowing celebration meals, and finally maintaining weight loss through a balanced diet, oat bran supplementation, and daily exercise.
However, this diet has drawbacks, such as strict rules to follow and a high protein requirement. According to a study, the initial high-protein phase may increase the risk of kidney stones as an unpleasant side effect. Individuals with a history of kidney stones should reconsider trying out this diet, as advised by the study’s authors.
10. The South Beach Diet
The South Beach Diet is a weight loss diet that differs from other low-carb diets by focusing on lean protein and healthy fats. It allows “good carbs” after the initial phase, as highlighted by the Mayo Clinic. While the diet provides convenience with frozen meals and minimal cooking, it involves purchasing their branded snacks and food, which can limit choices. Moreover, relying on packaged foods may result in missing out on the full nutritional benefits of whole foods. A study comparing popular diets, including the South Beach Diet, found it to be very low in calories (around 1,200) and lacking in 21 out of 27 essential nutrients examined, such as vitamin D, vitamin E, iron, magnesium, and zinc.
11. Carb Cycling
Carb cycling is a variation of the low-carb diet where you alternate between days of low carbohydrate intake (50 to 150 g of carbs) and days of high carbohydrate intake (up to 400 g of carbs), as explained by the American Council on Exercise. The specific plan you follow determines the number of high- and low-carb days. This approach, such as “Keto cycling,” modifies carb amounts while following the keto diet. According to Hultin, the main advantage is that having occasional higher-carb days helps individuals tolerate the lower-carb days and provides more energy for workouts, making it popular among athletes and specific training regimens. However, one drawback is that the low-carb days may make you feel restricted, leading to overcompensation on the higher-carb days. Hultin prefers a more balanced daily plan to avoid the need for precise calculations every single day.
12. Zero-Carb Diet
The zero-carb diet, also known as the carnivore diet, has gained popularity online despite lacking scientific research. This controversial diet involves consuming only meat and fat, which can lead to high levels of saturated fat and a lack of fiber, essential for digestion. Additionally, it excludes important sources of vitamins, minerals, and antioxidants found in vegetables and fruits. Since experts advise consulting a doctor before attempting even a ketogenic diet, which is less extreme, it is crucial to seek medical advice before considering the zero-carb diet.
