The Evidence Behind the Ketogenic Diet for Weight Loss

Ethos Ho, BSc Pharm Student

What is the Ketogenic Diet and How Does it Promote Weight Loss?

The ketogenic diet is a dietary strategy that significantly restricts carbohydrate intake to promote weight loss and other health benefits related to treating obesity.^1-4 The low-carbohydrate ketogenic diet (LCD), very low-calorie ketogenic diet (VLCKD), or simply ketogenic diets restricts daily carbs to 20 to 50 g while maintaining high fat intake.^1-4 When the body is deprived of dietary sugars and starches, it responds by reducing insulin secretion and begins burning fat within a week; a state known as nutritional ketosis.¹ During this metabolic state, the liver converts fatty acids into compounds called ketone bodies, which is an alternative source of fuel for our brain and body tissues.^1-2

Previous low-carb diets, such as the Atkins diet, which restrict fat while emphasizing protein intake, do not prevent the conversion of amino acids to glucose and therefore kicks the body out of ketosis.¹ With ketogenic diets, protein consumption is limited to adequate amounts to maintain lean body mass while fat or overall calories are not restricted.¹ Since a constant state of ketosis is maintained in the body, weight loss, as well as improved blood-sugar control, is achieved. This results in an array of health benefits for individuals that are overweight or obese with diabetes.

What does the Evidence Say?

There is a lot of evidence supporting the ketogenic diet for weight loss and overall health improvement compared to conventional dietary methods. Numerous well-controlled trials found that people on ketogenic diets lose more weight and keep more of it off than people on low-fat diets. People placed on these diets also often report decreased hunger. Although the reason for this is not fully understood, it could be related to:¹

• The satiating properties of fat and protein
• Changes in hormones regulating appetite
• The direct appetite-suppressing effect of ketone bodies

In addition to weight-loss associated with the ketogenic diet, studies also supported added benefits of improving blood-sugar control in diabetes and improving cardiovascular health. Studies have shown that individuals who were on the ketogenic diet found reduced HbA1c (a measure of average glucose levels), blood sugar concentration, triglycerides, bad cholesterol, systolic and diastolic blood pressure, glucose, insulin, and c-reactive protein levels (a measure of overall inflammation).^1-3 Overall, these benefits were found to be greater for individuals on the ketogenic diet compared to those on a low-fat diet.

How Safe is the Ketogenic Diet?

Although studies have found the ketogenic diet to be well-tolerated by many individuals; there are certain precautions that need to be considered for those interested in going on the diet.^1-3 The most common side-effects reported, collectively known as the “keto flu”, include lightheadedness, dizziness, fatigue, difficulty exercising, poor sleep, and constipation.^1-2 These side-effects are usually temporary and pass in a few days to a few weeks.¹ One way to help counter these side-effects is by getting protein from whole foods rather than purified protein products to ensure adequate intake of sodium, potassium, and magnesium in the diet. For those taking insulin or oral diabetic medications, consultation with an experienced healthcare professional is recommended due to the risks of serious hypoglycemia (low blood-sugar levels).¹

Something to Try: Omega 3 Tuna Burgers With Avocado Crema by Press Start Nutrition

Huge thanks to our friend Charlotte Press at Press Start Nutrition for providing this delicious, easy to make recipe. For more recipes like this, be sure to check out her website.

“These burgers are packed with healthy fatty acids from the omega 3s in both the tuna and the flax seed meal. Omega 3s are especially important in the American diet since most Americans get a lot of Omega 6 fatty acids but not very many omega 3s, and the balance/equality of these two is critical to maintain optimal health. These burgers also are easy, delicious and have a great texture in my opinion. Try them topped with my lightened up avocado “crema”.”

The following recipe serves four, takes ten minutes to prepare and 15 minutes to cook:

The Bottom Line

Ketogenic diets are high fat, low carbohydrate diets that help the body mimic a fasting state. This allows the body to primarily burn fat and produce ketone bodies, which are used as an alternative source of fuel for our brain and body tissues. Compared to conventional low-fat diets, ketogenic diets have proven to be more effective in weight loss, improving blood-sugar control, as well as reducing cardiovascular risk. The diet is generally safe and well-tolerated by many individuals, although medical supervision is recommended in those that are on insulin or oral diabetic medications due to the risk of severe hypoglycemia. A ketogenic diet is an option for those who are looking to lose weight, control their diabetes, or improving their overall health and are ready for the challenge of significantly reducing carbohydrates in their lifestyle.

As always, we hope you took away something valuable from this piece. If you have any questions or concerns regarding this article or others, feel free to reach out to us on Instagram, Facebook, or at ask@orbishealth.ca with your feedback. We’d love to hear from you.

RESOURCES

1. Bueno, N., de Melo, I., de Oliveira, S., & da Rocha Ataide, T. (2013). Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. British Journal Of Nutrition, 110(07), 1178-1187. doi: 10.1017/s0007114513000548
2. Abbasi, J. (2018). Interest in the Ketogenic Diet Grows for Weight Loss and Type 2 Diabetes. JAMA, 319(3), 215. doi: 10.1001/jama.2017.20639
3. Goday, A., Bellido, D., Sajoux, I., Crujeiras, A., Burguera, B., & García-Luna, P. et al. (2016). Short-term safety, tolerability and efficacy of a very low-calorie-ketogenic diet interventional weight loss program versus hypocaloric diet in patients with type 2 diabetes mellitus. Nutrition & Diabetes, 6(9), e230-e230. doi: 10.1038/nutd.2016.36
4. Williams, T., & Cervenka, M. (2017). The role for ketogenic diets in epilepsy and status epilepticus in adults. Clinical Neurophysiology Practice, 2, 154-160. doi: 10.1016/j.cnp.2017.06.001