Is the Keto Diet Safe?
Why all the fear?
By Steve Anthony
Before digging in, let’s first discuss what a Keto Diet is and how the meaning of the term has changed of late:
The keto (ketogenic) diet, as a conscious deviation of the “typical” diet, is one that typically holds the daily intake of carbohydrate to 20 grams or less, or 5% of daily calories. Protein is typically set at 20% of calories and fat at 75%. In recent times, the ketogenic diet has been used to treat epilepsy. Before the treatment of diabetes with injected insulin, it was also treated with a ketogenic diet. Some believe, and with good reason, that we evolved eating a diet with macronutrient ratios similar to that of a keto diet.
Recently, the term keto is frequently used to refer to any low or even low-ish carb diet. SO not every source that discusses or recommends a keto diet is discussing or recommending what is now often referred to as a “medical” (or true) keto diet.
That said, I’ll be discussing the safety of a true keto diet — the more extreme version of a low-carb approach to eating.
When you do a Google search on the keto diet, you frequently see links with titles like “The Dangers of the Keto Diet” or “Popular Keto Low-Carb Diet Could Have Long-Term Consequences, New Studies Reveal” or “Ketogenic diet: What are the risks?” Makes you think twice about trying the low-carb approach to eating.
What puzzles me is why anyone would think eating a low-carb diet would be unsafe or come with associated risks.
Carbohydrate is a non-essential nutrient for humans. That is, we don’t get anything we need from carbohydrate that the body can’t produce from other things we eat (namely protein or fat). So, while there are 9 essential amino acids we get from protein and 2 essential fatty acids we get from fat, there are no essential carbohydrates. Yes — carbs get broken down into glucose. And we need glucose. But if we don’t eat carbs, our body makes glucose out of — wait for it — body fat! What could be more elegant than a system that uses our own fat for fuel?
So why would anyone think NOT eating a non-essential nutrient would be unsafe? Why do the fields of Nutrition and Medicine say “we need more research” to make sure it is safe? Cocaine is non-essential to humans, yet we don’t say NOT using cocaine needs more study before we can proclaim a non-cocaine lifestyle “safe.”
Let’s look at the potential “risks” the University of Chicago sees in the ketogenic diet:
They rightly point out that “If you are on diabetic medication that causes low blood sugar, those meds may need to be adjusted within a few days.” What they don’t say is that the “adjustment” will be a reduction in the patient’s meds — because there will be lower levels of blood glucose to deal with. So yes — if you are a diabetic, don’t go on a keto diet without consulting your doctor. Fair enough.
They also point out that “there are heart-healthy sources of fat, however if that person is not educated on heart-healthy sources of fat, they may consume excessive amounts of saturated fats that can increase your risk of heart disease.” Well, not exactly. Yes — if you don’t know what fats to stay away from, you might eat unhealthy fats. But saturated fats are NOT unhealthy nor does eating them lead to heart disease. In fact, being on a high saturated fat, keto diet leads to improvement in all heart-health markers. What increases your risk of heart disease is a diet high in carbohydrate. Yup — you read that right. The low-fat/high-carb diet recommended by the American Heart Association to prevent heart disease causes heart disease. And, the whole low-fat food industry, and all the “heart-healthy” products on the market today, actually increase your risk of heart disease.
But back to the University of Chicago.
While they don’t offer any support, they claim that “The keto diet could cause high blood pressure [it’s actually been shown to lower blood pressure], kidney stones [it has actually been shown to improve kidney function], nutrient deficiencies [all the micronutrients you need are available via protein and fat], an increased risk of heart disease [actually the keto diet improves all heart-health markers cardiologists look at] and constipation. Okay — yes, at first, you might find you don’t evacuate your bowel as often. But this is not blockage — it’s the fact that your body is using more of the food you are eating, so you have less to get rid of.
They then cite “strict diets like keto could also cause social isolation or disordered eating.” I suppose if one is a fanatic about it — but it seems more amenable to socializing than the Vegan diet. I have nothing against vegans, but they really are a drag to socialize with, even if they aren’t trying to make you feel guilty for eating animals. I go out to eat and to parties all the time and stick to a low-carb diet. And I live in Italy — land of pane (bread), pasta and pizza. I just get the salami & cheese appetizer and a protein plate — and skip the bread and pasta. Although, I will admit that over Christmas, I went over my 20 grams of carbs for a few days. But that’s not dangerous.
They state, “Keto is not safe for those with any conditions involving their pancreas, liver, thyroid or gallbladder.” Sure — so if you have a medical condition, talk to your doctor. But one liver condition keto is good for is fatty liver disease. A keto diet can actually reverse that disease and rather quickly.
They also point out that “someone new to the keto diet can also experience what’s called the ‘keto flu’ with symptoms like upset stomach, dizziness, decreased energy, and mood swings caused by your body adapting to ketosis.” This is true, but I would hardly classify it as a “risk.” I went through this. It lasted maybe a week. Note: “your body adapting to ketosis” means “your body adapting to using your body fat for fuel.” Put that way, it doesn’t sound so bad — especially if you are overweight, have tried dieting all your life with no success and now the pounds are melting away.
They close by saying “they wouldn’t recommend the keto diet to their patients because it is ultimately not realistic or sustainable. The diet restricts fresh fruits and vegetables, whole grains and low-fat dairy that can help with long term weight loss and overall health.” Well, the keto diet doesn’t prohibit any of those food except low-fat dairy (full-fat is MUCH better for you). So there is no risk here, either. I’ve been eating a keto diet for over a year now — it’s not difficult at all. I still eat vegetables and fruit (although I avoid potatoes and bananas).
If you know of controlled research that shows keto is dangerous, please let me know in a comment. But be aware, very little research in the field of nutrition is of a level of control that allows for claims of causation to be made. Many seem impressive because they include tens of thousands of people. But those studies (called epidemiological, or, association studies) cannot make conclusions of causation. “Factor X is associated with Outcome Y” is NOT telling you that Factor X causes Outcome Y — even though the media often reports it that way. These association studies are useful in identifying potential factors to test in controlled studies. But this is rarely done because it is incredibly expensive to do.
References for this article:
Hallberg, S et al. (2018) “Effectiveness and Safety of a Novel Care Model for the Management of Type 2 Diabetes at 1 Year: An Open-Label, Non-Randomized, Controlled Study,” Diabetes Theory, Apr; 9(2): 583–612.
Griffin, B. et al. (1994) “Role of plasma triglyceride in the regulation of plasma low density lipoprotein (LDL) subfractions: relative contribution of small, dense LDL to coronary heart disease risk,” Atherosclerosis, Volume 106, Issue 2, April, Pages 241–253
Santos, FL et al. (2012) “Systematic review and meta-analysis of clinical trials of the effects of low carbohydrate diets on cardiovascular risk factors.” Obesity Review. Nov;13(11):1048–66.