Throughout the years, different forms of dieting emerged and became a trend. From the Paleo diet 1, to Sirtfood Diet 2. From veganism3 to intermittent fasting4. There are so many types of diets to choose from.
Despite being primarily used as a treatment for epilepsy back in the 1920s 5, ketogenic diet 6 has been an emerging food trend since the early 2000s, with more and more research studies being published each year. But what really is a ketogenic diet? Would it be safe enough for you to follow?
What you need to know about Keto?
The ketogenic diet works by limiting your body’s intake of carbohydrates, thus forcing your body to break down glycogen (the process is called glycogenolysis8). Once glycogen has been depleted, your body is then forced to break down fat to become ketones which can serve as a rich source of energy (through a process called ketosis7). By constantly minimizing the consumption of carbohydrates, and meeting your recommended protein intake, your body will continue to utilize your stored fats as a rich and steady source of energy.
Ketones, as the alternative fuel source, tend to become healthier than glucose as it is more efficient in providing energy with less metabolic waste 9. Since a person normally has more stored fat than stored glucose (in the form of glycogen), entering the stage of ketosis would mean that you can go a lot longer without feeling hungry, and especially without craving for carbohydrate-rich food. Thus, consistently putting your body in a state of ketosis may mean that you will not easily crave nor get hungry. Therefore, the longer you continue your ketogenic diet, the easier it will be for you to continue this diet long term.
Furthermore, for you to stay on track in catabolizing stored fats by achieving the ketosis state, maintaining high levels of ketone in the blood is a good indicator. For most people, knowing that their bodies are in a ketosis state, they become more motivated to stay on track with their low carbohydrate and high fat diet. With the appropriate tools, monitoring your blood ketone levels is a lot more doable at home and without having to go through painful procedures in laboratories.
Eating Fats and Losing Muscle Mass
Although some researchers have argued that losing weight through a ketogenic diet can lead to muscle atrophy 10 (which refers to the decrease in the size of muscle tissue), it may not necessarily be the case if you follow the diet properly and avoid drastic decrease in your intake of calories. Furthermore, despite the changes in your energy levels during the early phases of ketogenic diet journey, there are ways on how to burn fats without losing your muscle mass, such as keeping yourself physically active and following an exercise training, along with maintaining a balanced protein intake and giving yourself some time for rest and recovery between strenuous physical activities.
Despite multiple studies that established that ketogenic diet is not significantly different than its high carbohydrate counterparts in terms of building muscles 11,12, it is highly important to consider that it is the act of lifting weights (which promotes the synthesis of muscle proteins 13) which is responsible for gaining muscle mass. Although carbohydrates provide the necessary energy for people who do not follow the ketogenic diet to keep on lifting weights, it is necessary to understand that carbohydrates have no direct contribution for muscle growth. Among people who follow the ketogenic diet, the high fat intake provides the steady energy needed for an aerobic or a muscle strengthening exercise.
Moreover, as part of your ketogenic journey of losing weight and building muscles, you must remember that despite protein’s involvement in muscle building, protein intake must still come in moderation, as high protein intake can prevent you from getting into the state of ketosis 14. Amino acids, as the building blocks of protein, can still be converted into glucose (through a process called gluconeogenesis 15). The abundance of these glucose (as a byproduct of gluconeogenesis) can shift your body back to using glucose as a primary source of energy, thereby hampering the breakdown of your stored fats. Thus, maintaining the right proportion of carbohydrate, protein and fat in your diet is quintessential in keeping your weight loss journey successful.
What to eat and What to Avoid while on Keto?
The Harvard School of Public Health recommended that in following a ketogenic diet, 70-80% of your total daily calorie intake must be obtained from fat, 10-20% must be coming from protein, while only 5-10% of your calorie intake is obtained from carbohydrates. Therefore, an average person who consumes around 2,000 calories daily must include around 165 grams of fat, 40 grams of carbohydrates and 75 grams of protein in his diet.
Following a ketogenic diet by maintaining the correct proportion of carbohydrates, proteins and fats is now more achievable because of the multiple sources that are now readily available online. Although, it is highly important to note that not all ketogenic diets are the same because some are considered “clean”, while others are considered “dirty”. The clean ketogenic diet involves consuming low-carb, high-fat foods that are prepared and consumed in their “natural state”, without the presence of additives and added sugars. Therefore, choosing clean ketogenic foods can lead to a lot of health and financial benefits among others. Below is a list of top examples of clean ketogenic foods.
- Shellfish (i.e., clams, oysters and mussels which are also good sources of trace minerals and Omega-3 fatty acids),
- Leafy Greens (High in fiber, low in carbohydrates),
- Fresh sardines
- Steamed cruciferous vegetables (i.e., Brussels sprouts, broccoli, cabbage, cauliflower, etc.)
- Olives (or Olive oil)
- Grass-fed beef
- Peanut butter (choose the unsweetened ones, with no added flavors)
On the other hand, the worst foods to avoid while following a ketogenic diet include the following:
- Corn (High in carbohydrates)
- Potatoes (Very high starch content)
- Yogurt (which normally has high sugar content)
- Commercial chicken (they are mostly genetically modified)
- Processed meat (because of the added sugar and nitrates)
- Processed cheese (High in Saturated fat, and some are also high in carbohydrates)
- Foods high in oxalates (i.e., spinach, almonds, soy products etc.).
Although a ketogenic diet may not work for some people, it has been proven to be one of the most effective and efficient ways to lose weight. However, like all other dietary and exercise programs, being informed with the pros and cons of the ketogenic diet, staying physically active and being persistent in following the recommended meal plans are three important keys to a successful ketogenic journey.
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3. Greenebaum, Jessica. “Veganism, identity and the quest for authenticity.” Food, Culture & Society 15.1 (2012): 129-144.
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5. Wheless, James W. “History of the ketogenic diet.” Epilepsia 49 (2008): 3-5.
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10 Nakao, Reiko, et al. “Ketogenic diet induces skeletal muscle atrophy via reducing muscle protein synthesis and possibly activating proteolysis in mice.” Scientific reports 9.1 (2019): 1-14.
11. Wilson, Jacob M., et al. “Effects of ketogenic dieting on body composition, strength, power, and hormonal profiles in resistance training men.” The Journal of Strength & Conditioning Research 34.12 (2020): 3463-3474.
12. Meirelles, Claudia M., and Paulo SC Gomes. “Effects of short-term carbohydrate restrictive and conventional hypoenergetic diets and resistance training on strength gains and muscle thickness.” Journal of Sports Science & Medicine 15.4 (2016): 578.
13. Hermassi, Souhail, et al. “In-season weightlifting training exercise in healthy male handball players: Effects on body composition, muscle volume, maximal strength, and ball-throwing velocity.” International Journal of Environmental Research and Public Health 16.22 (2019): 4520.
14. Mobbs, Charles V., et al. “Treatment of diabetes and diabetic complications with a ketogenic diet.” Journal of child neurology 28.8 (2013): 1009-1014.
15. Silva, S. V., and J. R. Mercer. “Effect of protein intake on amino acid catabolism and gluconeogenesis by isolated hepatocytes from the cat (Felis domestica).” Comparative Biochemistry and physiology. B, Comparative Biochemistry 80.3 (1985): 603-607.