Just like evil, low carbohydrate diets come in many forms. ( Forgive the hyperbole)
One of those forms is the ketogenic or “keto” diet.
They say that An Apple A Day Keeps The Doctor Away… and the ketogenic diet takes that saying quite literally by allowing hardly more than an apple’s worth of carbohydrates on a daily basis.
Sounds crazy right?
Well…the ketogenic diet is essentially the king (or queen) of low carbohydrate diets.
On the keto diet you are meant to consume so few carbohydrates (the human body’s preferred source of energy) that your body actually starts using fat as a fuel source. When faced with prolonged carbohydrate deprivation, the body converts fat into compounds known as ketones and utilizes these ketones as an alternative energy source.
This process is known as ketosis, and explains the origins of the name “ketogenic diet”.
How low do you have to go to achieve this? Most ketogenic diet literature that I’ve encountered preaches about 5% of your total calories from carbohydrate daily.
For reference, the recommended carbohydrate intake in a balanced diet is between 46-65% of calories from carbohydrate.
If you are on a 2,000 calorie diet , the keto diet allots you about 100 calories a day from carbohydrates.
That’s about 25 grams a day.
Here are a few examples of what 25 grams of carbohydrate looks like:
1 cup of cooked oatmeal
1 cup of sweetened Greek Yogurt
5” sweet potato
½ cup of quinoa
2 slices of whole grain toast
Now imagine that you could only choose a single one of these nutrient-dense carbohydrate containing foods per day.
That would be your life on the keto diet.
Now, the question I am left with is “why on earth would anyone want to do that to themselves?”
As far as I can see there are three primary physiologically-motivated reasons why someone might be motivated to carry out such a drastic dietary change:
- To lose or better manage their weight
- To reduce their risk of chronic disease
- To improve their physical performance
But guess what?! There is no truly meaningful or robust scientific evidence to suggest that the ketogenic diet does any of these things better than a healthy, balanced, carb inclusive diet.
Nor is there any strong evidence to suggest that the metabolic process of ketosis (using ketones for energy) confers any special health advantages over plain old healthy eating.
Most of the arguments (or evidence) that I encounter to the contrary to this claim are flawed or do not compare the keto diet to a truly high quality balanced diet.
So the question you need to ask yourself is, why bother?
Sure, theoretically a very well planned keto diet could be healthier than a very poor carbohydrate-containing diet, but at the end of the day, the keto diet is just another re-packaged low carbohydrate diet that can help you lose weight in the short term but does not offer any superior weight loss or magical metabolic effects when compared to a competently implemented, calorie-reduced healthy, balanced, diet.
In fact, the ketogenic diet asks you to take on an extremely restrictive and hard to maintain dietary pattern without really knowing what effect it will have on your health in the long-term.
It asks you to do this while essentially omitting foods that have been robustly proven to be vital to good health (namely fruits, whole grains and starchy vegetables).
So why does it garner so much attention?
Sadly, you can’t sum up healthy, balanced and inclusive diets with a single sexy word like “keto” and this is part of the problem we face promoting moderation in the nutrition community.
Polarized and extreme diet patterns draw so much attention for this reason.
They simplify eating in a dangerous way by creating artificial boundaries that stigmatize food groups and offer a short-cut, of sorts, to eating fewer calories.
People have short-term weight loss success on these diets because it is harder to get the same amount of calories in when you are essentially barred from eating any type of carbohydrate.
As part of this process, people may also cut out less useful carbohydrate rich foods like chips, candy, baked goods and refined grains like white bread.
The cost of cutting out these foods as part of a restrictive diet scheme means that other extraordinarily important foods like fruits, starchy vegetables and whole grains like steel cut oatmeal also eliminated.
In this way, it becomes very much an “eye for an eye” exchange.
If you are enamoured by the ketogenic diet, or are currently following it, ask yourself if you really believe that severely limiting your intake of fruits, sweet potatoes, quinoa and steel cut oatmeal (among many other ridiculously healthy foods) is truly the cornerstone of good health.
While you ponder this, be aware that the great majority of the most robust disease prevention and weight management evidence that currently exists suggests otherwise.
When you frame the question in this way and with that context in mind, I find it extraordinarily difficult to justify supporting any severely restrictive eating pattern, the ketogenic diet included.
Hope you guys found this useful!
Until next time,
Andy De Santis RD MPH
Addendum April 13th 2017
I’ve received some interesting negative comments regarding this article. To be clear, I am providing my professional opinion as to the (lack of) utility of this diet for the “average” adult looking for a healthy eating or weight loss fix.
Make no mistake, a diet that excludes whole grains, starchy vegetables, fruits and other nutrient dense sources of carbohydrate cannot, with the body of evidence we currently have on the impact of these foods on our health, possibly be considered healthy from a population perspective.
Could certain individuals improve their state of health from its current point using a ketogenic diet? Potentially, in the right context, and I admit as such within the text.
Could they improve their state of health even more with a balanced, carb-inclusive diet? Almost certainly.
That is my primary point in today’s article.
Until such a time that such strong evidence exists to prove the contrary, that these nutrient dense carbohydrate containing foods in fact should be restricted to achieve optimal health in the general population, I will happily maintain my stance on this diet pattern.
Please understand that I am not discounting this diet’s potential prescribed use in the treatment of epilepsy or other niche contexts. Nor do I discount the anecdotal cases of weight loss that you may have experienced with this diet. In fact, I admit in the article that such restrictive diets have the potential to help with weight loss.
Finally, for those citing metabolic studies as evidence of the superiority of ketosis. I see no truly high quality evidence of a profound metabolic benefit of ketosis that justifies the exclusions of all of the healthful foods required to achieve that state.
Again, that singular point underlies the motivation of this article as a whole.
If such robust evidence becomes available in the future, I may re-consider my stance on the topic. Until then, I don’t believe the vast majority of reasonable practitioners could or would justify the broad support of this highly restrictive dietary pattern.