The ketogenic diet, commonly known as the keto diet, has surged in popularity over the past decade. Touted for its potential to promote rapid weight loss and improve metabolic health, it has garnered attention from celebrities, athletes, and health enthusiasts alike. But is the keto diet truly effective for weight loss?

We’ll explore the science behind the keto diet, its benefits, potential drawbacks, and whether it is a sustainable option for long-term weight management.

Understanding the Keto Diet

The keto diet is a high-fat, low-carbohydrate eating plan that aims to shift the body’s primary energy source from carbohydrates to fats. By drastically reducing carbohydrate intake (usually to less than 50 grams per day), the body enters a metabolic state called ketosis. In ketosis, the liver converts fats into ketones, an alternative energy source, thus promoting fat burning.

This can be beneficial as apart from losing fat, you will feel more energized as fats contain 9 calories per gram, which is more than carbs and protein which have 4 calories per gram each, so you’ll gain more energy.

Typical Macros for a Keto Diet:

• Fats: 70-75%
• Proteins: 20-25%
• Carbohydrates: 5-10%

Mechanisms Behind Weight Loss on Keto

1. Ketosis and Fat Burning:
   The primary mechanism through which the keto diet promotes fat loss is ketosis. When carbohydrate intake is minimized, insulin levels drop, and the body shifts to burning stored fat for energy. This can lead to a significant reduction in body fat, especially in the initial stages of the diet.
2. Appetite Suppression:
   High-fat and moderate-protein foods are more satiating than carbohydrates, which can help reduce overall calorie intake and overeating. Ketones also have appetite-suppressing effects, reducing the chance of you binging.
3. Improved Insulin Sensitivity:
   The keto diet can improve insulin sensitivity and reduce blood sugar levels. This is particularly beneficial for individuals with insulin resistance or type 2 diabetes, as it can help stabilize energy levels and reduce cravings for high-carb foods. Because you’re consuming less carbs (especially refined ones), insulin has a better response to when you next consume a carb, and this can result in you even storing less fat from consuming carbs than before, as your body will eventually get used to burning fat as energy rather than storing much of it.
4. Increased Energy Expenditure:
   Some studies suggest that a ketogenic diet can increase the body’s energy expenditure due to the thermic effect of protein and the metabolic costs of gluconeogenesis (the production of glucose from non-carbohydrate sources).

Evidence Supporting Keto for Weight Loss

Numerous studies have examined the effectiveness of the keto diet for weight loss. Here are some key findings:

1. Rapid Initial Weight Loss:
   Many individuals experience rapid weight loss in the first few weeks of starting the keto diet. This is partly due to the loss of water weight, as glycogen (stored carbohydrates) is depleted from muscles and the liver, releasing water in the process.
2. Sustained Weight Loss:
   A meta-analysis published in the British Journal of Nutrition 2013 found that individuals following a ketogenic diet lost more weight than those on a low-fat diet over one year. The keto group also showed greater reductions in triglycerides and blood pressure.
3. Preservation of Lean Body Mass:
   High protein intake on the keto diet helps preserve lean body mass (muscle), which is crucial for maintaining metabolic rate during weight loss. Because less insulin is released, more growth hormone is produced, an inhibitor of muscle loss.
4. Reduced Visceral Fat:
   Visceral fat, which surrounds internal organs and is linked to metabolic diseases, is more effectively reduced on a ketogenic diet than on low-fat diets.

Potential Drawbacks of the Keto Diet

While the keto diet offers promising benefits for weight loss, it is not without its challenges and potential downsides:

1. Initial Side Effects (Keto Flu):
   During the first few days of transitioning into ketosis, many people experience “keto flu,” a collection of symptoms including fatigue, headache, dizziness, nausea, and irritability. These symptoms usually subside as the body adapts to using ketones for energy. Fortunately, it’s short-term.
2. Restrictive Nature:
   The keto diet is highly restrictive, eliminating many fruits, grains, and starchy vegetables. This can make it difficult to maintain for most people.
3. Long-Term Sustainability:
   Adhering to a strict ketogenic diet over the long term can be challenging. Social situations like dining out or parties can lead to potential burnout and difficulty maintaining weight loss. However, these are usually once-in-a-while situations, and one day won’t affect your progress hugely unless you allow it to negatively affect the following days.

Compared to a calorie deficit

Weight loss fundamentally comes down to creating a calorie deficit, where you consume fewer calories than your body needs to maintain its current weight. This belief is known as “calories in, calories out”.

This deficit prompts the body to utilize stored energy, primarily from fat reserves, leading to weight loss. Understanding the mechanisms behind weight loss on a calorie deficit involves exploring how the body manages energy balance, the roles of metabolism, and the physiological changes that occur.

Here are the characteristics of a standard calorie deficit:

1. Energy Balance and the Caloric Equation

The principle of energy balance is central to weight management. Energy balance is the relationship between the calories consumed through food and drink (energy intake) and the calories expended through basal metabolic rate (BMR), physical activity, and the thermic effect of food (TEF).

Caloric Equation:

• Energy Intake: Calories consumed from food and beverages.
• Energy Expenditure: Calories burned through your basal metabolic rate, physical activity, and the thermal effect of food (as some foods digesting burn more calories, like protein).

When energy intake equals energy expenditure, body weight remains stable. A calorie deficit occurs when energy intake is less than energy expenditure, leading to weight loss.

2. Basal Metabolic Rate (BMR)

BMR is the number of calories the body needs to perform basic physiological functions at rest, such as breathing, circulation, and cell production. BMR accounts for about 60-75% of total daily energy expenditure. Factors influencing BMR include age, sex, weight, height, and body composition.

During a calorie deficit, the body may reduce BMR slightly as an adaptive response to conserve energy. However, this reduction is typically modest and does not negate the calorie deficit’s effect on weight loss.

3. Thermic Effect of Food (TEF)

TEF refers to the energy required to digest, absorb, and metabolize food nutrients. TEF constitutes about 10% of total daily energy expenditure and varies with the macronutrient composition of the diet:

• Protein: Highest TEF (20-30% of calories consumed).
• Carbohydrates: Moderate TEF (5-10% of calories consumed).
• Fats: Lowest TEF (0-3% of calories consumed).

A diet higher in protein can slightly increase TEF, thereby enhancing the calorie deficit and promoting weight loss.

4. Physical Activity

Physical activity is the most variable component of energy expenditure. It includes all forms of movement, from structured exercise to daily activities like walking, gardening, and household chores. Increasing physical activity can help create a larger calorie deficit, accelerating weight loss.

Cardio and HIIT are popular for weight loss as you burn more calories in a short time.

Components of Physical Activity:

• Exercise: Planned, structured activities such as running, cycling, and weightlifting.
• Non-Exercise Activity Thermogenesis (NEAT): Daily activities like walking, fidgeting, and maintaining posture.

Potential Drawbacks of the calorie deficit

However, food is not just calories and you shouldn’t think about it that way. The thought of “calories in, calories out” isn’t as effective and sustainable long term.

Because although some foods may be low in calories, the food itself can give different responses to food hormones, like insulin, which is a fat-storing hormone. And the higher the GI of that food, the larger the spike in your blood sugar, and the more fat you’ll store.

Here are some more drawbacks:

1. Nutrient Deficiencies

One of the most significant risks of a calorie deficit is the potential for nutrient deficiencies. When calorie intake is reduced, it can be challenging to obtain all the essential vitamins and minerals needed for optimal health, without going over the calorie intake.

For example, people may choose lean fish over fatty fish, but fatty fish have healthy fats, which aid in fat loss, and vitamin D which many people lack, and it’s fat-soluble.

2. Insulin spikes & fat gain

Many people on calorie deficits are recommended to eat frequently rather than a few times to prevent hunger. However, eating small, frequent meals will make you more hungry than eating a few, large meals.

Every time you eat, insulin is released to deal with the food (especially the carbs), and the more frequently you eat, the more insulin is released, this is bad because along with your body storing more fat, it inhibits growth hormone production which is crucial for maintaining muscle mass and increasing your metabolism.

It can even decrease your insulin sensitivity, so more glucose will be left in your blood which can lead to pre-diabetes and then diabetes.

3. Increased Hunger and Cravings

Consuming more calories will give you energy so you don’t feel hungry. But consuming less calories will result in you feeling more hungry, as you simply don’t have enough energy. Combine this with frequent eating, and you’ll feel even hungrier.

4. Limitations on Food Choices & lack of sustainability:

• Dietary Constraints: To maintain a calorie deficit, individuals often need to limit their intake of high-calorie, high-fat, and sugary foods. This can mean cutting out favourite foods, which can be psychologically and socially challenging.
• Reduced Portion Sizes: Eating smaller portions can leave individuals feeling deprived or unsatisfied, especially if they are accustomed to larger meals.
• Increased risk of binging: Because individuals are unsatisfied and hungry, they may be more likely to binge eat, resulting in them gaining fat and reversing progress.

Take the Keto Diet Route

The keto diet is great for fat loss primarily because it induces a state of ketosis, where the body burns fat for fuel instead of carbohydrates.

This metabolic shift leads to a significant reduction in body fat stores. Additionally, the high-fat, moderate-protein, and low-carb composition of the keto diet helps control hunger and reduce appetite, making it easier to maintain a calorie deficit.

The keto diet also stabilizes blood sugar levels, preventing spikes and crashes that can lead to cravings and overeating, and this leads to increased metabolism because of the increased production of growth hormones.

Furthermore, the consumption of healthy fats and proteins promotes satiety and muscle preservation during weight loss. Ketogenic diets often lead to rapid initial weight loss due to the depletion of glycogen stores and associated water weight. Lastly, the diet’s emphasis on whole, unprocessed foods supports overall health and can improve metabolic markers associated with obesity and fat accumulation.

Although you may not be able to consume many grains or fruits, there are still many other foods you can consume, which will satisfy you.

Tips to maintain a keto diet

Doing intermittent fasting with a keto diet is the best combo you could have for fat loss. Intermittent fasting further increases insulin sensitivity to a safe level and increases the production of HGH, which aids in muscle mass maintenance and recovery.

Here are some tips to consider when on this diet:

• Do 16/8 fasting (eat in a window of 8 hours, and fast for 16 hours), and consider increasing it to 18/6 and 20/4 if you can soon
• Consume 2 meals per day
• Don’t snack in between meals as you’ll spike your insulin
• Avoid refined carbs
• You can drink water
• Consume more healthy fats, medium protein and low carbs
• If you fall off the diet due to an event, like a party, don’t be dishearted and continue the diet the following day
• Consume nutrient-dense foods, like animal protein, healthy fats and low-GI fruits
• Avoid ultra-processed foods