Keto diets have gotten hugely popular in recent years, especially for weight loss. And while this approach works at first, many people find out that they can’t stick with it long-term.
Let’s dive in and explore why keto works, and why, outside of medical uses like hard-to-treat epilepsy in children, it isn’t the answer it is sold as. If you are on a ketogenic diet for epilepsy or another condition under medical supervision, please don’t change it without talking to your doctor.
What is Ketosis
When we eat no carbohydrates, our bodies enter a backup mode called ketosis.
Ketosis is an important adaptation, and humans are unusually good at it, especially as babies, whose fat stores help fuel a fast-growing brain. It has saved our species from starvation by letting us run mostly on our own fat reserves.
What allowed us to survive in harsh conditions was our ability to store calories as fat and then survive for days with no food.
Thank you, ketosis!
What about the health benefits?
Fasting gets a lot of attention, but the human trials are less exciting than the headlines. In a year-long trial, fasting every other day worked no better for weight, blood pressure or blood sugar than simply eating a little less every day, and more people gave up. Longer water-only fasts are not something to try on your own: even in a medically supervised clinic, more than a quarter of fasting stays involved a significant side effect.
Keto Diets
First, ketones are a perfectly good fuel. During a long fast they become the brain’s main energy source, which is exactly why keto is not a metabolic trick.
Keto diets do lose weight at first, but not by magic. When men ate exactly the same calories on keto as on a high-carbohydrate diet in a metabolic ward, keto did not speed up fat loss; fat loss actually slowed. What ketosis does is take the edge off hunger, so people eat less. And when researchers let people eat as much as they wanted, a low-fat, plant-based diet led them to eat about 689 fewer calories a day than an animal-based keto diet.
On a diet of mostly meat and fat with almost no carbohydrate, the body runs on fat and ketones much as it does during a fast.
Many people feel unwell for the first few days, the so-called ‘keto flu’, as the body uses up its stored carbohydrate and the water stored with it.
After that, appetite often drops: a 2015 review found that people in ketosis feel a little less hungry, and that is most of why keto diets lose weight at first.
With our appetite suppressed, we feel fine on less food, and we lose weight.
Keto diets allow us to lose the extra weight, but at the cost of a diet that is very low in fiber and short on several vitamins and minerals, and increasing our risk of developing cancer by building meals around red and processed meat, which the World Health Organization’s cancer agency lists as a probable cause and a cause of colorectal cancer, respectively.
Most importantly, ketosis is the body’s backup system for when we are starving. It’s meant as a short-term solution. We don’t want to be in backup mode in our daily lives. It’s dangerous in the long term.
Keto diets are a hack. You lose weight at the expense of long-term health. It works for a while, but it’s not healthy!
Read next
- The potato guide: the food keto treats as the enemy, and what it actually does in the body.
- What carbs are and why you need them: biology that the low carb argument skips over.
- How to eat carbs and still lose weight: same point, made practical.
Hi!
What about a very low-carb diet that is whole food based, rich in vegetables, nuts, seeds, healthy oil and berries? I get my proteins from eggs, fish and some wild meat and focus on consuming a lot of different and colorful vegetables. 100 grams of berries (wild blueberries and black currants) a day is my main source of carbohydrates.
I started eating low carb as I have struggled a lot with brain health and cognitive function, and I have found this to help. I don’t religiously stay away from carbs and might have a meal with some bread/potato/pasta now and then if I am visiting friends or family (or visiting a really good bakery on a seldom occasion!). This works fine in moderation, but I have recently found out that if I do it several meals in a row/a whole or a few days or just eat a lot of carbohydrates, my cognitive function seem to really plummet. My own assumption is that this happens as I am thrown (far) out of fat burning/ketosis, as when I resume to my own diet, or fast to get out of the unfortunate state faster(pun not intended ^_^), I get better again. The state I end up in when eating carbs/lots of it in comparison to low carb, is definitely not good for me as I really struggle. I do however care a lot about my health and want to take the right approach.
When you say that the body perceive ketosis/fat burning as starvation, is this the case even if one consumes enough energy through a lot of fat/are not in a calorie deficit? – Is it still unhealthy, even if one eats nutrient-dense and healthy foods? Do you have any simple tips to a balanced approach?
Best Regards,
Emilie
Hi Emilie,
I am sorry that you are experiencing such health problems.
First, I must point out that the Keto diet was initially conceived when doctors discovered that children with epilepsy responded very well to fasting, and putting them on a fast-mimicking diet (i.e. keto) helped them tremendously.
That said, fat burning for the human body is extremely inefficient and, more importantly, releases a lot of acidic byproducts in the bloodstream.
Also, the body isn’t very well equipped to deal with excess fat and if you overconsume fat, it will start to get deposited in places where you don’t want it to be like on the inside lining of the blood vessels, between the cells of the internal organs, inside the brain and inside the actual cells. To oversimplify, this leads to the development of heart disease, type 2 diabetes, and degenerative brain diseases such as Alzheimer’s. In fact, the gene that is thought to predispose people to Alzheimer’s disease ( APOE-e4) is actually a variation of the gene that controls the removal of fat in the brain. Basically, people with APOE-e4 have a worse ability to remove fat from their brains (and probably develop plaques and Alzheimer’s).
When people eat no food (i.e. fast). the body runs out of its preferred fuel – carbs and starts to burn fat for energy AND selectively consume protein from its tissues for energy as well. I say ‘selectively’ because the body will always remove the tissues that aren’t necessary or less important for our survival first.
Therein lies the incredible healing capabilities of fasting – our bodies are made primarily of fat and protein. When we fast, the body removes what isn’t necessary, what is ill.
What’s more, when we fast, our metabolism downregulates and we use the least amount of energy that can sustain us. The body has no influx of fat or protein. No fat can be stored anywhere because it’s released from our fat storage and consumed for energy.
And the fat that is released in the minimal amount necessary.
Now, compare this to consuming only foods that contain no carbohydrates but only fat and protein. If we are about to live in this way for a long time, we are consuming not the bare minimum we need, we are consuming a lot more and over a longer period of time.
We cannot judge how much energy we need and we are probably going to overconsume since fat stimulates the appetite.
Also, protein stimulates growth (muscle growth, fat cell growth, cancer growth…) and has an acidic metabolism as well.
Now, fasting is done for a small amount of time and has healing effects because we allow the body to do what it is naturally designed to do – consume as much fat and protein from our own reserves as it needs but no more.
Fast-mimicking diets expose the body to a high acidic load for long periods of time and we have to judge how many calories it needs (which most people overestimate). It’s difficult to do right because it’s not natural.
If you overconsume fats, they are going to get deposited where you don’t want them to. Excess protein will stimulate the growth of tissues you don’t want. It’s difficult to judge and this is a huge part of the problem with keto diets.
I think that you are experiencing such great results on a keto diet because you are doing it more or less right and you are able to control your symptoms.
Still, if the moment to eat something else, the symptoms come back, the keto diet is probably like a band-aid and not exactly healing the underlying issues.
What is the perfect diet, though?
Humans are designed to eat plant foods (you can watch this https://www.youtube.com/watch?v=NMN1Zo_c7_A )
In my opinion, the perfect diet consists mainly of green vegetables, especially sprouts.
Greens are the perfect food, they are low in calories and richer in nutrition than any other food.
So, in a perfect world, you need to be consuming 10 or more servings of (mostly raw) greens per day and any other vegetables as well.
Then come legumes and whole grains. Steamed or boiled, not roasted, baked or exposed to dry heat. These are the perfect sources of calories.
Fruits are great but if you think you have carb sensitivity, you might eat them in moderation.
Nuts/seeds in moderation as well. Walnuts, flax and chia are the best.
In the end, I would advise you to seek a free consultation with Alan Goldhammer from the True North Health center. I think that he is the best person to help you.
All the Best
Venny