Ketogenic Diets – Top or Flop?
Ketogenic diets seem to be a trend again – in the last weeks several people told me they were on this high fat – moderate protein – very low carb diet. Interestingly enough those were all women with a preference for veganism/vegetarianism – diets that tend to be rather high in carbohydrates and low in protein…
So, what's all the hype about? What are potential benefits of eating that way? Is it healthy for everyone? Are there any downsides or risk factors? In this article I am exploring all of this and give you my Metabolic Typing-Mind-Body-Nutrition take on ketogenic diets.
What are ketogenic diets?
Ketogenic diets are very low carb – high fat diets that encourage the body to burn so-called ketones for energy rather than carbohydrates. If available, carbohydrates (glucose) are the preferred fuel for the brain (and also the muscles), since those are very easily available. Yet in their absence the body can also derive energy from ketones. Ketones are a result of fat (and also selected protein) burning. The ability to produce ketones is an evolutionary advantage, because our body can only store an approximate 24 hours supply of glucose/glycogen. We would have died out very quickly, if our body (including the brain) could not rely on ketones from fat as its main source of energy. That said, you need to reduce carbohydrates dramatically and consistently to get into the ketogenic state (< 50 g carbs per day over at least 2 days, some sources even put the limit at only 20g carbs per day). The calories from carbohydrates have to be replaced and this is usually done through ingesting higher amounts of fat (proteins can also be converted into glucose if eaten excessively).
What do you eat on a ketogenic diet?
Basically low starch vegetables (leafy greens, white & green vegetables), animal protein (meat, chicken, fish, dairy, eggs… and lots of fat (oils, butter, avocado, fat naturally contained in animal foods, some nuts & seeds…). You avoid all grains, pulses (lentils, beans, peas), fruit, potatoes, starchy vegetables, too many nuts and of course sugar, sweets, nectars, alcohol… The recommended macronutrient ratio is 75% fat, 20% protein and 5% carbohydrates.
What are the supposed benefits of ketogenic diets?
By burning fat rather than carbohydrates, ketogenic diets are often recommended for weight loss, especially to lose malign belly fat. They are also said to help with blood-sugar related ailments, such as diabetes or insulin resistance, improve lipid and cholesterol levels, starve cancer and yeast, detox the body (since toxins are stored in body fat), improve mental health (and even help with certain brain disorders, such as epilepsy), reduce high blood pressure and inflammation in general. They also promise improved and more steady energy (due to the stabilization of blood sugar, the fact that fat burns “slower” than carbs and the supply of fat-soluble nutrients that nourish certain organs and glands).
Are there any downsides / risks?
Ketosis vs. Ketoacidosis
Let’s first look at the rather common perception that ketosis is a dangerous state, because it over-acidifies the body. Some people, including doctors, confuse ketoacidosis - an extremely abnormal form of ketosis - with the normal benign dietary ketosis resulting from a very low-carb, ketogenic diet or fasting.
Benign dietary ketosis (also called keto-adaption) means that the body - and especially the brain - changes from relying on glycogen as its main source of energy to relying on ketones from fat. As long as a person can produce insulin (and be it only in very low amounts), the release of fatty acids and thus the ketone production is mild and well-regulated to not flood the body with too many of those (slightly acid) ketones at once.
The problem begins when a person cannot produce any insulin - like a type-1-diabetic or when an insulin-dependent type-2-diabetic does not inject enough insulin (diabetic ketoacidosis) or during alcoholic binges. Then the regulation mechanism fails and the body is flooded with uncontrolled, big amounts of ketones at once, which holds the risk that they build up in the bloodstream and acidify the blood to a dangerous level. This condition can be noticed in a typical fruity breath (acetone), nausea, hyperventilation, dehydration and lowering of blood pressure. It is usually treated with insulin to regulate the release of ketones.
As long as you are not type-1-diabetic (or a late-stage insulin-dependent-type-2-diabetic), you do not need to worry whatsoever about ketosis resulting from low carb consumption. To the contrary, a reduced carb diet is a way to actually prevent type-2-diabetes.
Other potential health risks
Depending on what exactly people eat on their ketogenic diet, it can lead to severe nutrient deficiencies. Some people eat only animal foods while avoiding all vegetables. Obviously, this is not balanced. Others still try to maintain their vegan preference, so basically living on oils and vegetables, but not ingesting any high-quality protein. Obviously, this is not balanced either. Vegetarians run the risk that they heavily rely on eggs and dairy for protein, which are among the most reactive foods.
Are ketogenic diets for everyone?
Ketogenic diets are often cautioned for people who are on medication for diabetes or high blood pressure and also for pregnant women. Apart from that advocates recommend them for anyone, including athletes and children.
My take as a Metabolic Typing Advisor
You probably guess it already: There is no “one-size-fits-all”. Whether it’s low fat or high fat, high carb or low carb, vegetarian or paleo, raw or cooked, eating 3 or 5 meals, eating breakfast or intermittent fasting … there is no single way of eating that benefits each and every person.
Even though we share a basic human physiology, we are all different on a biochemical level. Just like we have unique fingerprints, we also have different “Metabolic Types” that developed in function of geography, climate and natural food availabilities. What works for one person, might have no effect in another person and make a third person worse. The same food can have different effects in different people, even if it is a food that is considered to be “healthy” or “natural”. For example, inuit tribes evolved mainly on fatty fish, because hardly any plants are growing in the ice. Their metabolism adapted to thriving on and deriving energy from fats and proteins, basically a ketogenic diet. On the contrary, tribes in a tropical climate had an abundance of carbohydrate-rich plant foods at their disposal, which they would combine with fish or small animals. A ketogenic diet would not serve their metabolisms adapted to derive energy from carbohydrates. Instead of focusing on the food and its characteristics, we need to look at the person who is eating the food, because different Metabolic Types require different FUELS (macro- and micronutrients) and fuel MIXES (quantities of those nutrients).
While many people would benefit from a reduced carbohydrate intake (and a better quality of those carbs), for most going keto is not necessary - and can even lead to negative consequences for their health in the long run. Especially in women and carbohydrate/mixed Metabolic Types the adrenal glands and the thyroid need some amount of starch. If you are recovering from a burnout (and an excess of sugar and carbs might indeed have contributed to that situation), you should thus be very careful before omitting all or most carbohydrates, since you might just go from one extreme to another. 100-150g of carbs per day seems to be a gentler mark for most people – which is still much lower compared to the 300+ g of a "standard" diet.
My personal experience
Personally, I went from a very low fat, almost vegan diet to a high fat-moderate protein-low carb diet in 2012 (not ketogenic though). While my body was definitely fat deficient and there have been many benefits to loading up on fat, after a relatively short time my body gave me clear signals that I was feeding it more fat than it could handle: My cholesterol (including the “good” one) skyrocketed, there were some signs of liver congestion (like difficulties to convert beta-carotene to vitamin A and an orange tint to my skin…). It also showed in my stool and the complexion of my face. Adding in more carbs (especially cooked whole grains) has helped all of this for the better. I still consider (the right) fats to be absolutely crucial for health and am still eating a lot more fat than I used to, but without going to extremes…
I have made similar observations with clients whose genetic Metabolic Type tends towards carbohydrate metabolism (even though their Functional Type might temporarily ask for more fat/protein): for a short time they might benefit from high fat, but as the metabolism recovers, it might quickly change types back towards the genetic type, and what used to work for them starts working against them… On the other hand, some clients, especially true protein types, really thrive on high fat diets also in the long term…
My take as a Mind-Body-Nutrition & Eating Psychology Coach
In general, going to extremes or vilifying any specific food or nutrient, whether it’s fat or carbs or meat… is not an indicator of a healthy relationship with food and body. Even though it might be a coincidence, it’s an interesting observation that the people who told me they were on this diet were all former vegans/vegetarians… I myself went from one extreme to the other, before eventually finding the middle way… Yes, sometimes we need to restrict certain foods or follow a specific diet for some time… but it’s important that we do it inspired by true self-love and not (unconscious) fear. That being said, trial and error are often the best teachers, so if you feel drawn to the ketogenic diet, go ahead and be a nutritional explorer. Nothing can replace experience and nothing is as powerful as feeling the effect something has in your own body.
There is no “one-size-fits-all” and metabolism is not a static thing. While we can and should explore different ways of eating, we have to really stay alert and listen to the body, its (changing) needs and the signals it is sending, instead of following a diet just because it’s a hype right now or because it used to work for us in the past.