The ketogenic diet focuses on the consumption of very low amounts of carbohydrate and high amounts of fat and has gained the public’s interest for its potential role in weight management. Research studies investigating the diet’s effect on weight loss have found promising results.

What Does Current Research Say? 

Various studies suggest that the ketogenic diet is an effective dietary pattern to promote weight loss through carbohydrate restriction.^1–4 A 2019 study reviewing the effects of nutritional ketosis concluded that there is compelling evidence for the use of nutritional ketosis for weight management.⁴ Despite the need for more long-term studies, current data show that the diet can result in improved weight, along with other metabolic profiles. One of the meta-analyses reviewed 13 randomized controlled trials that compared ketogenic diets to low-fat diets with a follow-up period of >12 months and concluded that very-low carbohydrate ketogenic diets resulted in a significantly greater weight loss than low-fat diets.⁵ Similarly, a 2020 meta-analysis investigating the effect of ketogenic diet on individuals with type 2 diabetes mellitus also found that the diet is effective in promoting weight loss.³ Following a ketogenic diet significantly decreased weight (mean = 8.66 kg), waist circumference (mean = 9.17 cm), and body mass index (mean = 3.13 kg/m²).

How Does It Promote Weight Loss?  

The underlying mechanisms behind ketogenic diet’s effect on weight are still being studied. The ketogenic diet is thought to induce a state of ketosis where the body breaks down and utilizes fat reserves as the primary source of energy instead of glucose, leading to increased fat oxidation and weight loss.^6–8 In addition, ketosis is often associated with decreased appetite and suppressed hunger sensations, which can contribute to reduced caloric intake. 

What Are the Potential Challenges?

Despite its effectiveness in promoting weight loss, challenges remain. One of the challenges is adherence.⁹ It is estimated that only half of the adults are able to adhere to a low-carbohydrate regimen even with educational support. “Keto flu” is commonly experienced during the initial period of adjustment.¹⁰ These short-term symptoms may include fatigue, headache, dizziness, nausea, gastrointestinal discomfort, and decreased energy, which may hinder adherence to the diet.¹¹ Thus, although current research suggests that the ketogenic diet can effectively promote weight loss, more long-term studies are needed to study the safety, effectiveness, and sustainability of the diet over an extended period of time.