The ketogenic diet,1 or more broadly a diet that recommends carbohydrate restriction below 50g/ day or so has two big criticisms2. The first is that LDL goes up in some people, which may increase the risk of cardiovascular disease. The second is that it’s not sustainable3.
Discussing LDL in the context of increased saturated fat intake and its association with heart disease risk requires getting into the weeds. I’ll defer writing my opinion on it for next time.
However, stating that the ketogenic diet makes for a suboptimal intervention because long-term adherence is poor is problematic. Who decides what the sustainability threshold is, and for whom is it not sustainable? More importantly, how does the sustainability of the ketogenic diet compare to that of other lifestyle interventions?
For example:
Is 150 minutes of exercise a week sustainable? Apparently not for most.
Is a vegetarian or plant based diet sustainable? Unlikely any more than keto
What about the DASH diet? Mediterranean diet? Unlikely. All advocated by the same major institutions that seemingly discount the keto diet for it’s poor long term adherence.
Is avoiding processed foods sustainable? Many Americans would say no.
To reverse disease and improve health, something has to change. There must be some sort of restriction, some amount of discomfort, and disruption to the lifestyle that led to disease in the first place. Adopting a carbohydrate restriction is a major change. But so is exercise for someone who has never exercised. Or a low fat diet, or a vegan diet, or Mediterranean or DASH diet. The keto diet may have poor long term adherence in the general population, but compared to what? And what are more sustainable alternatives?
I don’t mean to defend the keto diet and suggest it’s a superior option experts don’t want you to know about. But I’m not sure why the keto diet in particular has been singled out to hold the reputation for poor long term adherence. All other supposedly healthful diets are difficult to adhere to as well. Otherwise, most Americans would have chosen one and prevalence of chronic disease wouldn’t continue to grow exponentially.
Taking a step back, however, studying and debating the adherence of a dietary intervention across a general population may be more distracting than it is helpful. A better question may be, What is the difference between those who successfully maintain a particular diet long-term, and those who don’t?
I use “ketogenic” loosely and interchangeably with carbohydrate restriction. Technically, there are differences.
I know there are a lot more, but I think these two receive a lot of media attention
Sustainable as in long term adherence, and not related to the environment
I like Paul Saladino's take on diet and healthy weight: choose food that is nutrient dense and delicious and don't focus on restriction because it's a recipe for failure. Of course, there's more to it than that but I think the general idea is well-founded. We need to find good options that we enjoy - perhaps, bring back traditional foods and the rich culture that attended them...