In recent years, the ketogenic diet has emerged as a prominent dietary trend, captivating the attention of health enthusiasts and researchers alike. But what exactly is the ketogenic diet, and how does it promise to revolutionize weight loss? Let's delve deeper into the origins, mechanisms, and potential benefits of this increasingly popular eating regimen.

Obesity is a pressing global health issue affecting both wealthy and lower-income nations, increasing the risk of diabetes, heart disease, and cancer, and facing societal stigma. Defined by the World Health Organization as a BMI of 25 or higher for overweight and 30 or higher for obesity, it's estimated that around 38% of the world's population aged five and older were overweight or obese in 2020, with projections indicating a rise to 51% by 2035. The economic burden is substantial, with costs predicted to escalate from 1.96 trillion U.S. dollars in 2020 to 4.32 trillion U.S. dollars by 2035. 1

Individuals with a higher body weight often experience psychological challenges like low self-esteem and depression. There are limited medical interventions available for managing obesity, with most relying on comprehensive lifestyle intervention programs. This lack of effective medical options can lead to frustration among those with obesity, prompting them to turn to extreme dietary measures for rapid weight loss. One extreme dietary approach is the ketogenic diet2. The ketogenic diet (also known as the keto diet) is being increasingly promoted as a strategy to fight obesity3. It has been widely discussed in popular culture through endorsements by celebrities, coverage in health magazines, and documentaries. As the popularity of the ketogenic diet grows, researchers are actively investigating its effects on individuals' health. While there is evidence supporting its benefits, particularly in terms of weight loss, there are also associated risks and concerns4.

The origin of ketogenic diet

The historical roots of the ketogenic diet stretch back over a century, originating from observations made by two physicians in Paris in 1911. These doctors noted that epileptic seizures were less severe during periods of starvation, setting the stage for the therapeutic use of fasting in epilepsy treatment. Fast forward to 1921, when Dr. Rollin Woodyatt made a groundbreaking discovery while studying starvation: the appearance of acetone and beta-hydroxybutyric acid in the body. This revelation led to the understanding that a low-carbohydrate diet could mimic the effects of fasting by inducing a state of ketosis.

Dr. Russell Wilder expanded upon these findings, coining the term "ketogenic diet" and championing its application in the treatment of childhood epilepsy. However, with the development of more effective epilepsy medications, interest in the ketogenic diet waned temporarily.

In the 1970s, the ketogenic diet found a new purpose thanks to Dr. Robert Atkins, who introduced the concept of nutritional ketosis for weight loss in his influential book. Atkins emphasized the importance of reducing carbohydrate intake to stimulate ketone production, thereby curbing hunger. This paved the way for a surge in the popularity of various low-carb diets, including the South Beach Diet, Paleo, and Mediterranean diets, each offering their own unique approaches to achieving weight loss and better health.

Despite evolving dietary trends, low-carb diets have stood the test of time as a mainstream option for weight management. Over the years, numerous studies have explored their efficacy not only in shedding pounds but also in improving chronic health conditions. As scientific research continues to uncover the mechanisms underlying ketosis and its benefits for weight loss, the ketogenic diet has risen to prominence as the preferred low-carb approach, capturing the attention of both the media and the general public alike4.

What is ketogenic diet?

The ketogenic diet is characterized by its low carbohydrate intake, moderate protein consumption, and high-fat content. In the classic ketogenic diet, individuals typically consume around 10–15 grams of carbohydrates per day, along with one gram of protein per kilogram of body weight, with the remaining calories sourced from fats5. This dietary approach aims to induce ketosis, a metabolic state where the body shifts from using carbohydrates as its primary fuel source to utilizing fats for energy production. Ketosis is believed to facilitate weight loss by promoting the breakdown of fat stores and reducing overall calorie intake due to increased satiety. Additionally, ketosis may contribute to improved blood sugar control and lipid profiles, making the ketogenic diet a popular choice for individuals seeking to manage their weight and improve metabolic health4.

How is the keto diet helping you lose weight?

When you eat fewer than 50 grams of carbohydrates a day, your body switches to burning fat for energy instead of glucose. This triggers two important processes: gluconeogenesis, where your liver makes glucose from other substances, and ketogenesis, where fats are turned into ketone bodies for energy. These ketone bodies, like acetoacetate and beta-hydroxybutyrate, become a primary fuel source for your body during a low-carb diet, a state called "nutritional ketosis." This is different from ketoacidosis, a dangerous condition with very high ketone levels. Ketone bodies provide efficient energy for your heart, muscles, and brain, crossing the blood-brain barrier to fuel your brain cell6.

Is keto diet worth trying?

While ketogenic diets have gained popularity and may lead to impressive short-term weight loss, caution should be exercised before starting one. While short-term results are promising, long-term effectiveness compared to other calorie-restricted diets is uncertain, as adherence to such a restrictive eating pattern can be challenging. Additionally, initial weight loss may be partly due to water loss rather than fat loss, potentially inflating short-term success. For individuals with type 2 diabetes, a ketogenic diet may help lower A1c levels and reduce medication needs, but careful adjustment of diabetes medications is necessary to avoid hypoglycemia. However, the long-term safety and health effects of ketogenic diets are still unclear, particularly regarding lipid profile changes and cardiovascular impact. While some studies show improvements in HDL and triglycerides, the response of LDL cholesterol varies, possibly due to individual diet content. Those considering a ketogenic diet should be advised to limit saturated fat intake and ensure adequate consumption of fruits and vegetables to maintain micronutrient and fiber intake. Ultimately, whether a ketogenic diet is worth trying depends on individual preferences, health goals, and willingness to adhere to a strict dietary regimen. Consulting with a healthcare professional before starting any new diet is recommended4.

Risks and long term sustainability

The ketogenic diet may lead to adverse effects such as low blood pressure, kidney stones, gastrointestinal issues like constipation, deficiencies in essential nutrients, and an elevated risk of cardiovascular disease. Following strict diets like keto could also potentially result in social withdrawal or the development of disordered eating habits. It is not recommended for individuals with pancreatic, hepatic, thyroid, or gallbladder conditions due to safety concerns. Additionally, newcomers to the keto diet may experience what is known as the "keto flu," characterized by symptoms such as gastrointestinal discomfort, lightheadedness, fatigue, and mood fluctuations as the body adjusts to ketosis7.

Studies have shown promising short-term results in reducing fasting glucose and hemoglobin A1c levels, but long-term efficacy remains uncertain. Additionally, there are concerns about hypoglycemic risk and ketoacidosis in type 1 diabetes patients following a ketogenic diet. Regarding cardiovascular health, there are variable responses in lipid profiles, with some studies showing increased LDL-cholesterol but others reporting decreased triglycerides and increased HDL-cholesterol levels. Diet composition plays a crucial role in these lipid changes, highlighting the importance of a balanced diet with adequate fruit and vegetable intake and limited saturated fats. Finally, pregnant women on low-carbohydrate diets may have an increased risk of birth defects, emphasizing the importance of adequate folate supplementation and avoiding restrictive diets during pregnancy4.

Key insight

Ultimately, whether the ketogenic diet is the right choice depends on individual preferences, health goals, and willingness to adhere to a strict dietary regimen. Consulting with a healthcare professional before embarking on any new diet is recommended to ensure safety and suitability for individual needs. As research into the ketogenic diet continues, further insights may emerge to better inform its application and address concerns surrounding its long-term sustainability and impact on health.

References

1 Obesity worldwide - Statistics & Facts.
2 Ketogenic diets: Boon or bane?
3 Weight loss, improved physical performance, cognitive function, eating behavior, and metabolic profile in a 12-week ketogenic diet in obese adults.
4 A Review of Ketogenic Diet and Lifestyle.
5 Practice Paper of the Academy of Nutrition and Dietetics: Classic and Modified Ketogenic Diets for Treatment of Epilepsy.
6 Ketogenic Diet.
7 Ketogenic diet: What are the risks?.