We all like to stay in shape. But often it is our dietary habits that come in the way. From time to time we hear of different ways of dieting. They all have different approaches. But truly they all require cutting down food intake in some way or another.
Some ways include cutting down excess fat intake, while others highlight the importance of reducing carbohydrates in the diet. Then there are ways which involves fasting for a certain number of hours per day, by eating according to a time table. Actually; this diversity never ceases to end!
Starting a brand-new diet plan is not the problem. The beginning is often filled with a lot of determination and motivation. However, it’s sticking to that particular diet plan and continuing it for a longer period of time becomes the most challenging.
Often this inconsistency is due to our busy lifestyles. We find it difficult to put an extra time and effort into adapting to a new way of living. Getting rid of the quick, and easy yet, unhealthy ways, that we have always been practicing is no easy task.
Sometimes, it is not that we don’t want to nor we lack a strong will, but it’s that we are full of doubt and afraid to embark on new ways without proper convincing evidence to back it up.
In recent times, a novel way of eating became quite popular amidst individuals interested in weight loss called, the ketogenic diet. In fact, it truly became quite the talk of the town making everyone interested in knowing more about its potential pros and cons.
Table of Contents
The low-carb- high-fat; Keto Diet
Ketogenic diet, or commonly called, Keto diet, took the world by storm during the last couple of years. It involves consuming a lesser amount of carbohydrates, moderate proteins, and a relatively a higher proportion of fats.
When there is a low carbohydrate intake, sugar level (glucose) in the body decreases. As a result, the body starts utilizing fats instead of glucose to generate energy by converting them into another form of compounds called ketones. This entire process happens in the liver.
Ketones act as a main source of energy for brain cells as well. When this transition of energy production happens from glucose to ketones, the body achieves a metabolic state called, “ketosis”, in which fats act as the main source of fuel for energy production in the body.
Using a ketogenic diet has become so popular across the globe as one of the best and efficient ways of losing some excess weight. However, with its immense popularity, people have started asking questions; whether it is truly effective as everyone says it is to be or whether it just comes with a bunch of adverse effects overweighing so-called advantages.
Luckily enough there’s limited, but substantial scientific evidence to show that keto diet in fact can be beneficial in several aspects including a certain degree of weight loss. After all, it has been used in epileptic patients for many decades.
However, the journey with a ketogenic diet is not smooth and hassle-free for everyone. Some face rather unexpected difficulties along the way. So, are there any serious side-effects of keto diet? What kind of scientific evidence is available to substantiate them? Here we are trying to look into some much-needed answers to these burning questions.
1. The Keto-flu
Keto-flu is not actually a real type of flu like that caused by an infectious virus or bacteria. In contrast, it is rather an umbrella term used to describe a set of flu-like symptoms that affect individuals who are just newbies to a ketogenic diet.
Symptoms of Keto-flu
Many individuals complain of vague symptoms like headache, dizziness, fatigue, irritability, and nausea. In addition, lack of motivation, difficulty of concentration (brain fog) and difficulty of sleeping like symptoms also occur.
Often these symptoms start during the first few days or the first week of starting the ketogenic diet and gradually wane off over a period of 2-4 weeks.(1)
What causes this Keto-flu?
The exact reason behind ketogenic flu-like symptoms still remain a bit unclear. However, scientists believe that it is the change in the dietary pattern causing a shift from carbohydrates to ketone bodies, the main causative factor.
It takes some time for the human body to fully-adapt into a state where carbohydrate is no longer the main energy source. The initial few days in which ketones become the main fuel is also known as “keto-induction” period. It is also the time in which the above-mentioned side effects are at a peak.(1)
Over a period of about one month, ketones become the primary source of energy and the ketone levels in the body become stable. As a result, the adverse symptoms gradually start to fade away in a majority of affected individuals.
However, there’s still a bit of debate over other factors that might be contributing to cause ketogenic flu. Some believe that certain detox factors, immunologic reactions, or a change in gut microbiome might also have some kind of influence on occurrence of these symptoms.
Remedies for Keto-flu
Although, not entirely scientific evidence-based, there are some useful ways in which you can overcome these keto-flu symptoms. Most of these remedies are proposed by users in online forums based on their own personal experiences.
The core concept behind these remedies is to maintain proper hydration and restore electrolyte balance. There is a scientific explanation behind this.
When there’s a lot of ketones in the body, urine production tends to increase. Along with urine, electrolytes are also excreted. As a result, there’s dehydration and electrolyte deficiency in the body, resulting in adverse symptoms. Therefore, it makes sense that drinking adequate amounts of water alleviate those symptoms as it restores hydration back to normal level.
Besides, another popular way of reducing these adverse side-effects is to eat a bit of salt or add about half a tea-spoon amount of salt into a glass of water and drink along with it. Instead of drinking just water, a soup or a broth would be a better option. These methods actually restore the electrolyte balance within the body.
Instead of transitioning from a high-carb diet to a low-carb diet rather quickly, a slow and gradual approach is a better way to reduce the occurrence of unfavorable symptoms. This gives the body necessary time and space to adapt to the new circumstances.
People who consume a lot of carbohydrates, especially food items with refined carbs like pasta, white bread, and cereals might need a longer time for this high-carb to low carb transition. On contrary, there is even a group of individuals who do not experience keto-flu like symptoms at all.
If all the above remedies fail, there’s always the last resort of waiting for the storm of symptoms to pass by. After all, these adverse effects last only up to a couple of weeks maximum and feels a bit unbearable only during the first few days. A little bit of patience and endurance will definitely get you a long way as far as a keto diet is considered.
However, if these symptoms continue to last for more than a couple of weeks, in the same intensity, in spite of everything you do, then you might have to reconsider your options since keto-diet might just not be your thing after all.
2. Elevated levels of “Bad” cholesterols
Low-density lipoproteins (LDL) are “bad guys” in the world of cholesterols. They are the main culprit behind atherosclerosis that leads to cardiovascular diseases.
Most alarmingly, several recent scientific research data indicate that a ketogenic diet has the ability to increase these unfavorable cholesterol levels in the body. Meanwhile some studies show lowering levels of the “good guys”, aka, high-density cholesterols (HDL) as well while others show contradictory results; high HDL levels just like other forms of lipoproteins.(2)(3)
In a study, where two groups of young and healthy individuals participated, one group was given a low-carb, high-fat diet for three weeks while the other group was given a normal diet. The group who consumed the low-carb; high-fat diet showed a 44% increase in LDL-C (low-density lipoprotein cholesterol) at the end of the time period, while the other group showed no change at all.(4)
Scientists recommend that leaning more towards plant-based items like olive oil which contain unsaturated fats along with low amounts of saturated fat containing food items like red meat, is a more suitable alternative for people with metabolic or chronic diseases.(3)
3. Physical performance
The effect of a ketogenic diet on physical performance of a person still remains a bit controversial as different studies reveal contradictory findings. The main reasons for this discordance include changes in study durations, physical activities, and different genders assessed in each study.
Research data shows that when a keto-diet is used for a shorter duration like 7 days, it results in a reduction in the physical performance. However, when continued for about 14 days, the level of performance reaches near-normal levels once again. Still, they were unable to find any significant evidence to support that continuation of a keto diet for a longer duration would bring a positive impact on the overall physical performance. (5)
Another study done with participation of exercise-trained men and women revealed that a low-carbohydrate, ketogenic diet could impair anerobic exercise performance in these participants.(6) A keto diet has the ability to induce a mild, sub-clinical systemic acidosis in the human body. Acidosis limits the anerobic exercise performance. Therefore, when compared to a high-carbohydrate diet, a ketogenic diet is not ideal for a person engaging in anerobic exercises.
4. Bad Breath
Some people who follow a strict ketogenic diet experience a strong fruity smell coming out of their mouths. The ketone bodies; mainly acetone is the culprit behind this unpleasant smell.(7) When working out and sweating, this odor can become really strong.
This bad breath indicates that the body is converting a lot of fat into ketones to generate energy. The good news is; this smell usually does not last that long and disappears after a couple of weeks. Good hydration and a bit of mouth fresheners normally solve the problem without much hassle.
But if the odor continues to linger, it is necessary to maintain the degree of ketosis in the body at a certain level. Including an additional 50-70 g of carbohydrates in each meal is a good way of keeping ketosis under control.(8)
5. Constipation
The commonest cause for constipation is dehydration induced by ketosis. As a result, there is increased absorption of water from the intestines forming dry stools. One of the easiest ways to avoid this situation is to drink enough water.
Besides, ketogenic diets often lack adequate amounts of fibers in them. This reduces formation of enough stool bulk for defecation. Therefore, it is important to include, sufficient quantities of non-starchy vegetables or some other natural source of fibers in the diet.
6. Enemy of Gut Microbiota?
Scientific research on this particular subject show a variety of results. However, they all agree upon one thing; ketogenic diet has a great influence on the diversity of gut microorganisms. Whether it is a positive effect or a negative effect is an entirely different question.
Some studies report adverse effects such as reduced diversity of microorganisms and increased amounts of pro-inflammatory bacteria.(9) Consuming fermented food products, using pre-biotics and pro-biotics (useful bacteria) in a proper manner are options for ensuring gut health while being on a keto diet.
7. Temporary Hair Loss
Hair loss is a sign of micro-nutrient deficiency and starvation. Sometimes, when calorie intake is restricted in form of a low carbohydrate diet, this can happen. Studies done on animal models show that a keto diet can cause biotin like vitamin deficiencies as it increases their consumption within the body. (10) However, in most individuals, this automatically resolves within a couple of months. It is crucial to include as much as healthy sources of biotin and other vitamins in the diet to overcome this problem.
8. Reduction in Alcohol Tolerance
Many individuals on low-carb diets claim they have reduced tolerance for alcohol than they had before. However, there’s a lack of solid scientific research findings to support this claim. According to one theory, carbohydrates lower alcohol absorption in the stomach. That’s why most people try to eat before consuming alcohol. However, a keto diet has very low amounts of carbohydrates and this allows a greater degree of absorption of alcohol into the body. This ultimately results in reduced alcohol tolerance.
9. Keto Rash
This is a rare inflammatory condition of the skin which mainly occurs when the body is in a state of ketosis. It is also known as Prurigo pigmentosa. This is an itchy, red rash which is predominantly found in the neck, chest and the abdomen. There are several individual case reports of keto rash occurrence after initiation of a ketogenic diet.(10) External factors like sweat, sunlight, heat, and friction seem to aggravate this skin condition.
Not everyone on a keto diet develops this rash. However, research data shows that discontinuation of a ketogenic diet puts an end to this skin condition. Adding extra carbohydrates to minimize ketosis is another way of alleviating symptoms.
10. Muscle cramps in the leg
This is a common side-effect experienced by many individuals who are new to a ketogenic diet. It is sometimes even painful. This condition mainly occurs as there’s a lot of water and mineral loss happening in the body with a keto diet. This leads to dehydration in the body. This condition can easily be reversed with adequate consumption of water and minerals.
Who should avoid Ketogenic diet?
Individuals having diabetes mellitus and on insulin or oral hypoglycemic drugs have to be really cautious when consuming a ketogenic diet. They could suffer from severe hypoglycemia if their medications are not properly adjusted at the beginning of the dietary change.
Type-2 diabetics can commence a keto-diet under medical recommendation. However, individuals with Type-1 diabetics are not recommended this type of dietary change as they are more prone to develop ketoacidosis. There is evidence of case reports where Type-1 diabetics developing ketoacidosis triggered by keto diet usage.(11)
Even in Type-2 diabetic patients there exists evidence showing cases of starvation ketoacidosis.(12)
Ketogenic diet is contraindicated in several disease conditions. They include liver failure, pancreatitis, disorders of fat metabolism, disorders of eating and in various micro-nutrient deficiencies.(13)
Furthermore, keto diet is not recommended for anyone pregnant or getting ready to get pregnant as well. It is best avoided during breastfeeding too. Breastfeeding is an act which reduces carbohydrates in the body on its own. Therefore, it is unnecessary to cut down any extra carbohydrates intentionally. There are very rare cases of ketoacidosis reported in breastfeeding mothers who were on a keto diet at the time.
The truth be told; we still lack proper, substantial scientific evidence regarding the adverse effects of a ketogenic diet. There exists a void of quality research conducted on this subject which prevents us from arriving at definite conclusions.
So, far there is evidence showing minor side effects of a keto diet over a short duration of time. However, the long-term implications are still a bit vague. The biggest challenge is maintaining compliance over a longer period of time to see the necessary results.
On a positive note; the scientific knowledge regarding the ketogenic diet is still evolving and constantly updating. Hopefully, we will know more about this topic in the very near future.
References
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