Disclaimer: There are far more positives than negatives to the keto diet and most of these keto downsides are extremely rare. Additionally, most are temporary and likely attributed to the body’s negative reaction to breaking the sugar addiction.
One of the negatives of keto is that it’s not for everyone. People that have very low body fat, adolescent children, and pregnant women should not follow a strict ketogenic diet.
Most of the dangers of the keto diet are short term and the long term problems can be prevented by eating more vegetables and increasing electrolyte consumption, especially sodium.
The sugar addiction is real and shouldn’t be underestimated.
This study published in the National Library of Medicine suggests that constant access to sugar causes an increase in extracellular dopamine that is more like a drug of abuse than a food. These behaviors are then related to neurochemical changes in the brain that are similar to addictive drugs. All addictive drugs, from opioids to crack, create a powerful surge of dopamine in the nucleus accumbens. This is the pleasure center of the brain.
The word “addiction” comes from a Latin term for “enslaved by” or “bound to.”
The intent of this article is not to bash the ketogenic diet or to prove the keto diet is healthy, but only to discuss the negative aspects of keto for the sake of transparency and honesty. No diet is perfect and many feel that keto is even dangerous. Before I cover each of the downsides to keto (as listed above) I want to address the question:
Is the keto diet unhealthy?
Absolutely not, as long as you eat healthy fats, vegetables and don’t go down the path of dirty keto. Here is an in-depth explanation of dirty or lazy keto.
When I explain the basics of keto to the average Joe I say that that the keto diet is just replacing sugars and starches with vegetables and increasing your consumption of healthy fats. Why would that be unhealthy? For example, you can have five cups of broccoli and still stay under your daily 30 grams of carbohydrates limitation.
So, as you can see, as long as you eat the right kind of foods you can eat a lot of food on keto. I don’t know about you, but I don’t know if I could eat five cups of broccoli in one day.
Keto can become unhealthy if you don’t eat vegetables.
Most people that contend that keto is not healthy have never actually experienced the keto diet and have very little knowledge about it. Most only puppet some of the false myths and negative rumors that they have heard associated with keto.
Now let’s talk about the downsides of the keto diet
I’m not going to cover this topic because I wrote a thorough article on the keto flu you can access here. I would contend that most of the keto negatives are associated with this keto flu phenomenon. It’s a combination of the body’s resistance to breaking the sugar addiction, low electrolytes and the body adjusting to a new energy source.
For most people, it’s the first time their body has had to use fat as fuel as opposed to glucose. Becoming efficient at using fat as fuel is also commonly called being “keto-adapted“.
Not everyone gets the keto flu and some people get it worse than others.
It can last 2 to even 4 weeks in more severe cases. I would also contend that most people that focus on the downsides of keto have either had a bad experience with the keto flu or failed to make it through the keto-adaptation process.
We have to listen to our body, but sometimes our body lies to us. Some people try keto and feel crappy, they get the “keto-flu” and assume it’s unhealthy. I equate it to a heroin addict that quits heroin and feels crappy and goes through withdrawals.
Quite often, keto feels unhealthy at first because the body is struggling to adapt.
When I started keto I never got the keto flu because I eased into it gradually and drunk a keto flu tonic every day. The tonic helped balance my electrolytes. Here are some tips for starting the keto diet in a healthy manner.
For myself and many others, the primary downside to the keto diet is keto constipation. I was so obsessed with this topic I researched and wrote a monster article on how to prevent keto constipation.
Honestly, it’s not really constipation. You just don’t poop as often because you don’t have as much waste coming into your digestive system. Starches and prebiotic fiber feed your gut microorganisms and the keto diet is definitely a diet that lowers starch consumption.
The microorganisms I am talking about are the probiotic bacteria that help your digestive system digest food. We can counteract this to some extent by eating fermented foods, vegetables, and keto superfoods. The bottom line is you will just have to get used to not having the same frequency of bowel movements.
Here a few food/supplements that will help get the bowels moving:
- Fruit pectin
- Guar gum
- lignin (flax)
- Chia seeds
- Fermented foods and kefir
This can be difficult, family and friends have trouble accepting the ketogenic diet. There is so much keto fake-news out there that many people only want to focus on the negative aspects of the keto diet. It’s ironic when we were eating an unhealthy standard American diet (SAD), nobody said a word. When you are on keto everyone is worried about your health.
Do in-depth research before you make a choice about diet. Here is a source for what to look for when choosing the best long term diet.
People read the headline or hear a sound-bite about keto and don’t bother to read the entire article and all of a sudden they are experts on the low carbohydrate diet. I try to read almost every article on keto and I will tell you most headlines are just click-bait and don’t even reflect the real content of the article.
The addiction to sugar can be miserable and misery loves company.
Social non-acceptance is something you will have to deal with. I equate it with an alcoholic that quits drinking and then all of his drinking buddies don’t want to hang out anymore.
Keto is also challenging during the holidays when there is an overabundance of sweets on most tables. During Thanksgiving and Christmas people look at you funny when you pass on the pumpkin pie. I think it makes some people feel guilty because they know deep-down they should probably pass also. The good news is you don’t have to go without, there are plenty of low-carb, sugar-free versions of most deserts readily available.
Limited food choices
Another one of the negatives of the keto diet is shopping at the grocery store. This is especially difficult when you have young kids or a family member that isn’t on keto and/or doesn’t support the low-carb lifestyle. It can also be expensive if you buy organic, grass-fed, free-range food products.
Yes you can have peanut butter on keto, but take it easy
However, there are ways to mitigate the challenge. If you can’t afford it, organic grass-fed is not mandatory, and if you have a good keto-friendly shopping list before you go to the market, it makes it easier to shop. You can also buy frozen meat and vegetables and buy a lot of your food in bulk. Here is a good Costco keto shopping list if you have a Costco card.
Overcoming the “hangry feeling”
This is another phenomenon that I am totally infatuated with. I have never understood why we get “hangry. Why in 2018 was it added to the Websters Dictionary? Think about it, the Websters’ dictionary was published in 1864, so why after 156 years was the word “hangry’ just recently added?
If you want to know more about being hangry you can access my research document here: Why we get Hangry.
The bottom line is when you start keto your blood sugar will go down you will probably feel irritable and uncomfortable. Understanding and overcoming this abrupt change to your blood sugar is one of the keys to having success on the ketogenic diet.
Increased cholesterol (possibly)
My goal here is not to convince you that cholesterol is good or bad. I encourage you to do independent research and keep an open mind without any preconceived beliefs. My goal is to inform you there is a good chance that your total cholesterol will go up. On the keto diet, you will eat more fatty foods that tend to be higher in cholesterol so it stands to reason that cholesterol can go up. Also, check the ratio of HDL (good cholesterol) and LDL (bad cholesterol).
I will also encourage you to take a look at the other bio-markers besides cholesterol. For example triglycerides, blood sugar (A1C), blood pressure, inflammation and liver enzyme levels almost always improve under keto. Try to look at the big picture when evaluating the keto downsides and don’t disregard how you look and feel.
Without bias, I googled the topic of keto and cholesterol and this is the conclusion of the #1 science-based study:
In other words, the ketogenic diet has been shown to lower triglycerides and raise good cholesterol (HDL) more than a low-fat diet. Do independent research and get a second opinion, but follow your doctor’s advice and don’t stop taking prescribed medicine until cleared by a doctor.
If you are convinced that keto is safe then find a keto-friendly doctor. They are getting easier and easier to find as more research emerges showing that the positives out-way the negatives of the keto diet.
Difficulty eating out at restaurants
This is a very minor downside of the keto diet in my opinion. Most people that adopt the keto diet don’t eat out as often because of their mindset changes. The keto lifestyle supports the idea that we eat to live, not live to eat.
However, it is far more difficult to eat out. Most of the items on most menus are not keto-friendly. Remember my comment about being hangry? Americans are eating more and more sugars and starches and restaurant menus reflect that. Even foods that were traditionally keto-friendly like meat are now slathered in sugary sauces and breading.
Salmon is one of the top keto super-foods, but it’s hard to find salmon at a restaurant that isn’t honey glazed or rubbed in brown sugar. I find myself ordering a salad and/or naked, non-breaded chicken wings and water with lemon most of the time. It’s even difficult to find vegetables at restaurants these days. Fortunately, some family-style restaurants still have a vegetable of the day.
I really didn’t want to include this as one of the negatives of keto. I think it’s way over-blown due to an article that went viral on the Huffington post called keto crotch. It originated on Reddit from a user by the name of u/imisswaffles. The thread was called: HELP LADIES! Why do I smell down there!? PCOS/Keto Crotch? let’s just say I am skeptical of the accuracy of this thread and subsequent article.
I read the explanation and it doesn’t make scientific sense. It was described as a possible yeast infection. We know that sugar feeds yeast bacteria. Sugar is added to a SCOBY (symbiotic culture of yeast and bacteria) to ferment kombucha and other fermented foods. So if anything a lack of sugar in the urinary tract would lessen the chances of a yeast infection.
There are some reports of keto-rashes, but it’s rare.
A keto rash is more than likely a result of the body’s reaction to breaking the sugar addiction, electrolyte or hormonal imbalances. For example, as of this writing, the Ketogenicinfo Facebook Group has 3,270 members and I can’t remember a single comment about keto rash, and I read every single comment and post.
To prove my point, Jardiance (empagliflozin) also called a gliflozins, is a new class of drugs to treat type 2 diabetes. It works independently of beta-cell function in the pancreas and helps the body pass the excess sugar/glucose out through the urinary tract.
One of the side effects of Jardiance is yeast infections. The extra sugar in the urinary tract feeds the yeast bacteria. When on the ketogenic diet there is much less sugar entering into the body and subsequently much less passing out through the urinary tract. Imisswaffles might have been on Jardience or she might have eaten too many waffles? She should have eaten a keto chaffle instead.
If you are interested in keto and diabetes I am extremely proud of an article I wrote titled: Can keto reverse type 2 diabetes.
This negative aspect of keto is also fairly rare, but in all fairness, it needs to be mentioned. I researched this topic and found the best source of why some people suffer hair loss here on Virta Health. It is a rare, temporary condition that usually lasts less than a year. It is caused by a combination of one or more factors:
- Stress/lack of sleep
- Improper nutrition (zinc, biotin, iron, vitamin C, A, E, and D, B complex, omega 3 fatty acids)
- Hormonal changes
- Calorie restriction
- Rapid weight loss
- Not enough protein (collagen)
I can’t sugar coat this one. One of the legitimate downsides to the keto diet is bad breath. You can read more about ketones and the state of ketosis here, but when you’re in ketosis your body expells the excess ketones as acetone from your breath.
Ketogenesis is your body breaking down fatty acids into ketones that you can use as energy. The primary ketones are beta-hydroxybutyrate, acetoacetate, and acetone. The excess beta-hydroxybutyrate is expelled in your urine and the excess acetone is expelled from your breath.
Ketones are beneficial and healthy and it’s not really a negative aspect of the keto diet except people that you come close to will smell your bad breath. It has a slight metallic taste in your mouth and smells similar to fingernail polish.
Brushing your teeth can help a little and also chewing on some sugar-free gum, but in all reality, it’s just something that you’re going to have to deal with. Drinking water and green tea can also help and as you get keto-adapted the keto breath becomes less of an issue. Remember ketones in your breath and urine just mean that your body is making more ketones than you need.