Several weeks ago, I began a diet review series and I did a brief synopsis of the Keto Diet. I admit it wasn’t very thorough and because I keep seeing it pop up and another friend starting it, another friend losing weight with it, and another person swearing by it for their increased energy, I’m gonna do a more thorough review here. I especially see my friends in the holistic communities doing it- and it’s spreading faster than the Whole 30 diet once was.
Is this the newest fad that will be replaced by something better in a couple of years? Or is it here to stay and in several years we are going to see evidenced based research popping up at how it’s the best diet that we never knew existed and if we just figured out how healthy fat was for us earlier, maybe we wouldn’t be seeing the rise of heart disease, obesity, cancer, and other related diseases that we do today?
Well, let’s start with what it even is. Roughly 70-75% fats (you read right), 5-10% carbohydrate, and 20-25% protein. As you can see this is not your normal low carb diet that typically replaces the missing carbs with protein. It’s all about the fat. Why? Because the purpose of this diet is to put your body into ketosis, aka a fat burning machine. Just to give you a little science lesson here, our bodies preferred source of fuel is glucose (what carbs are converted to after we eat them). Now if you are eating a diet high in carbs, that is what you will burn first for energy. And everything requires energy in our bodies to function properly, including our brains. When the body runs out of glucose (will happen if you aren’t eating very many carbs), the liver is great at producing a back up, called ketones. Ketones come from broken down fat. Make sense?
So why do people do this? I dunno about you, but while a high fat diet sounds pretty fun to me, a diet made of mostly fat doesn’t. But there are lots of anecdotal reports of promising results when one follows this kind of diet. I’ll start with two that have evidenced-based research backing the claims up (because you know me, that’s what I’m about.)
Note: it was very difficult for me to find any studies published prior to 2017 (soooo….6 months ago) that called a ketogenic diet low carb high fat. Be aware of that because any other “ketogenic” diet before that in the research was defined as “low carb, high protein.” There is a huge difference and that’s not what we are talking about here. I worked with patients and personally participated in 2 published studies on very low calorie high protein, low carb diets for 7 years.
Weight loss: this article published in 2013 reviewed 12 different studies and found in 1415 subjects, the average weight loss after 6 months on a high fat, low carb diet was 2 pounds vs. 1.6 pounds for those following a low fat diet. After a 6 month follow up it was difficult to assess because compliance was not so great and they consumed more carbs than allowed. Another study published in 2009 was done for a full year on 106 obese individuals and compared weight loss of those on a keto diet vs a low fat, high carb diet. They found that their average weight loss was the same between groups, both losing an average of 30 pounds. Pretty good, but neither diet was superior to the other. It just showed that following a reduced calorie diet yields weight loss.
I will add here that I’ve always said, I’ve failed at what I do if I helped you lose weight but you regained it all back. I don’t think we know enough about this diet for the purposes of weight loss to know if it’s not just another yo yo plan. Sorry.
Lipid levels: In the same 2013 review, they analyzed 1258 subjects and found their triglycerides decreased significantly, and their HDL levels increased significantly. Both good things. I like that and the amount of subjects is enough to say it’s valid.
Other indicators of Metabolic Syndrome: The 2013 review noted there was no significant difference between treatment groups in changes in systolic blood pressure (11 trials), fasting blood glucose (eight trials), insulin (six trials), HbA1c – average blood glucose over three months (four trials) and C-reactive protein (four trials).
Athletic performance: In this 2017 review, they concluded that long-term low carb, high fat diets appear to be safe and may even improve several metabolic risk factors for chronic diseases in the general population. They may even provide a promising way to help control body weight and fat mass while maintaining lean body mass in athletes who are participating in sports like tae kwan do, wrestling, lightweight rowing, cycling, and running. Additionally, there is some emerging evidence that a keto diet could improve the performance in ultra-endurance sports as well as those sports with repeated high intensity activities. If you aren’t an athlete, this could still be a good thing if you’re hitting up the gym and wanna try out that new cycling class.
Focus and Mood: this has been one result that many believers love the most. And why I believe they stick with it. Who wouldn’t when you feel great, you’re losing weight, and you’re better able to focus? Who doesn’t need that? Here’s what the available research says: in a 2009 study, they found that after 8 weeks, those following both low carb, high fat diet and a low fat diet had significant improvements in their mood and cognitive functions. However, after a year, the low carb, high fat diet returned to their baseline mood and cognitive functions while those on the low-fat diet continued with their marked improvements. You read that right. The low-fat diet group continued with the better mood, NOT the keto group. This study here in 1998 reported similar results on women eating a high carb diet. I’m just the messenger, don’t hate me! Now, I’m not recommending you go eat a bunch of carbs to feel better. Okay?
Here’s the thing, the concept of following a keto diet for weight loss is fairly new in the research world. So you’re not gonna find a whole lot out there to prove it does a whole lot for health yet. You will find a bunch out there to show the benefits of what it does for those with epilepsy unresponsive to medication. It works.
And don’t expect overnight results. It takes time for the body to adapt to ketogenesis. Some sources I’ve read say two weeks, others say up to a couple of months – assuming you don’t go off plan, not even once. So no cheat days allowed. This diet is for the type A strict meal planning types. Those who are willing to keep a food record and count their carbs, fats, and proteins will do best.
I’m a weight loss expert. And here’s what I know about long term, sustainable weight loss. It’s hard. Like, really hard. If you’re looking for a study that proves ANY diet to work and be the ending answer to our obesity epidemic, well good luck. You will surely find that one person who followed a high carb diet and lost 167 pounds and now has kept it off for 13 years. There’s gonna be that person following the Atkins diet since it’s introduction to the dieting world and it’s changed their life forever. And then there’s the rest of the dieting world still looking for what works for them. I did not find anything that said following the ketogenic diet was harmful, not even long term. In fact, quite opposite. So if you wanna try it because you know someone or more than a few someones who are following it and now they look and feel great and you think it’s something that could help you, well let me know! I’m always looking to be inspired by someone’s dieting success story.
P.S. If you’re looking for online support with like minded moms striving to live a healthier lifestyle, you may be interested in joining my free support group here.
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Jillian McMullen, RDN, CSOWM, LDN