I promised my readers the answers to some common questions on the Ketogenic Diet, and backed them up with research. Here there are:
Is KETO a starvation state?
How long do glycogen stores last?
Is this the same as keto acidosis?
Won't a diet high in fat cause weight gain?
Won't a high-fat diet increase my risk for heart disease?
Doesn't saturated fat increase your cholesterol?Aren't low-fat diets a better way to lose weight?
1) Biochemically speaking, the KETO diet is a starvation state (1). During starvation we have no more glucose stores and the body turns to protein, and then fat - to produce energy for fuel (in the form of ketones). Technically on KETO, you are not starving because you are eating enough calories. KETO just swaps the glucose (sugar) out for fat (ketones)
2) Glycogen stores will be depleted after approximately 24 hours (2). Glycogen is the storage form of glucose. Once your body uses the glycogen stores up, it turns to protein for fuel, and then after about 72 hours, your body begins to use fat for fuel. Your body will 'spare protein' because protein is much more valuable than fat. Protein provides us with muscle structure and also enzymes that help to keep our body running. When fat is broken down it produces ketones which can be used instead of glucose. So, as you can see, the KETO diet forces the metabolism into a survival mode, similar to what would happen during starvation. Interesting!
3) No, ketosis is NOT the same as ketoacidosis. Ketoacidosis is a term used for a medical emergency when the Type I diabetic no longer produces enough insulin. Insulin is a great regulator in the body for glucose and energy management. When it is no longer produced, the body spirals rapidly out of control and the level of ketones rises to 20-25 mM in the blood (1). This is accompanied by excessive urination, thirst, nausea and an alteration in consciousness (confusion and even coma). Emergency treatment is essential. In contrast, on a ketogenic diet, the body is regulating glucose and fats normally. The KETO fat-burning diet puts the body at a ketone level of only 4-5 mM, and this does not pose a risk to a healthy individual.
4) No, a high-fat diet is simply replacing carbohydrate calories with fat calories. As long as you are not overeating, there is no reason to assume that eating fat will create fat. You should not gain weight on a high-fat, low-carb diet.
5) Increased risk for heart disease is possible. I believe this is very likely because in order to achieve the 65% or more percent of calories from fat, you have to consume 'fat bombs' which are typically high in saturated fats. However, if you consume more fat from healthy sources like avocados and olive oil, this can be mitigated - according to a Harvard Health report (3). Well, unless you are committed to consuming several avocados and a small cup of olive oil every day, that mitigation is not likely. Believe me, I love avocados, but after a month of 3 avocados a week, I really don't want to look at another one anytime soon. On this diet, I tried to keep down the saturated fat intake, but I did not feel satisfied on healthy fats. Once you start recognizing how full and satiating cream cheese and bacon are, you will struggle with anything else. See, there are no comforting carbs to fill that void.
6) Yes, saturated fat DOES increase your LDL, or bad cholesterol and is a strong risk factor for CVD. (4) The American Heart Association agrees and notes "Decades of sound science has proven it can raise your bad cholesterol and put you at higher risk for heart disease." (5) Here is where I get my nutritionist mode amped up. It is only the advocates for the KETO diet that are dismissing the saturated fat/ heart disease data (6). Dieter beware. Most of the studies that show reduced heart disease risk have been done on RODENTS. Human studies are limited and have mixed findings (7). Finally, as a nutrition advocate, I know that severely restricting nutritious complex carbs to 5% of your intake WILL run you into nutritional deficits. Supplementation is absolutely necessary. I collected data on my KETO diet for a month and posted results on my FB page.
7) The jury is still out on whether or not you should go low-carb or low-fat when dieting . What studies do show is that both diets types will work short term, and that long-term weight gain is likely (8). What you need is a sustainable and healthy eating style, not another diet fad like KETO.
The KETO sales pitch:
Traditional diets are high in carbs which provide ample glucose. When you eat glucose, you trigger and insulin surge. Repeated snacking on carbs triggers so much insulin release, that your cells become 'insulin resistant.' (This is a real possibility). So, the insulin can't get the glucose into your cells, which makes the blood levels of glucose rise, formation of triglycerides rise and your overall health trends towards diabetes. All because of the glucose rich carbohydrates. The natural conclusion is that reducing carbs will reduce insulin levels, insulin resistance goes away and the body learns to use fat for fuel. Hurrah! It seems they have a solution to obesity and heart disease!
That's where we really need to educate ourselves. We are not rats in a cage. We have complex metabolic functions that are not the same as rodents. And to think that this is easy as swapping fat for carbs is really quite silly if you ask me. BUT I wasn't willing to stop there. I am putting diets like KETO to the test for the next 12 months.
Here's my final take:
This diet is HARD. I committed to it for a month, and I did not like it at any point. I love food. I love healthy nutritious balanced food. There is nothing healthy or nutritious about the KETO diet. According to my diet tracker on www.cronometer.com, I got less that half of the required fiber, and my meals fell woefully short of Vitamins C, D, E, B1, B5, B6, and Folate. I was also very short of my RDA for the following minerals: calcium, copper, iron, magnesium, manganese, potassium and zinc.
I am so thankful for the inspiration that drove me to test 12 Diets in 12 Months. There is a lot of misinformation in the media that preys on what people want to hear, rather than help them along their journey. You deserve better than that.
I am a nurse.
I am a nutritionist.
I am a health coach.
If you are looking for clear answers from someone who has walked the walk, then contact me. We can work as partners to discover the right nutrition for you.
Until next time,
Be Kind to Yourself!
1. Fedorovich, S. et al. 2018. ‘Ketogenic diet versus ketoacidosis: what determines the influence of ketone bodies on neurons?’ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6199956/
2. Khan Academy. 2020. ‘Introduction to energy storage.’ https://www.khanacademy.org/test-prep/mcat/biomolecules/fat-and-protein-metabolism/v/introduction-to-energy-storage
3. Harvard Health. 2017. ‘Getting to the heart of the fat issue.’ https://www.health.harvard.edu/mens-health/getting-to-the-heart-of-the-fat-issue
4. Briggs, M. et al. 2017. ‘Saturated Fatty Acids and Cardiovascular Disease: Replacements for Saturated Fat to Reduce Cardiovascular Risk’ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5492032/
5. The American Heart Association. 2020. ‘Saturated Fat.’ https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/fats/saturated-fats
6. A subscription is required to access their website and article on ketogenic diets. www.dietdoctor.com
7. Kosinski, C. and Jornayvaz, F. 2017. ‘Effects of Ketogenic Diets on Cardiovascular Risk Factors: Evidence from Animal and Human Studies.’ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5452247/
8. Doheny, K. 2017. ‘Best Diet for Weight Loss, Your Choice: Low Carb vs Low Fat.’ https://www.endocrineweb.com/news/obesity/59074-best-diet-weight-loss-low-carb-vs-low-fat