Skip to content

Top 13 Side Effects Of A Low Carb Diet

Constipation, Bowel Movement

Experts explain why you experience odd symptoms like bad temper and confusion when following a keto diet.

The past few years have seen the keto diet develop a considerable following, with a number of famous people, such as Katie Couric and the Kardashians, talking highly of its advantages.

People recognize keto as being beneficial for weight loss, but it can also lead to a feeling of satiety for longer periods of time, increased energy levels, and decreased desires for unhealthy food items.

It is possible to do the keto diet in a sensible manner, however, there exists a couple of bizarre adverse effects to look out for, particularly, “keto flu”.

Unlike Atkins and South Beach, the keto diet emphasizes fat rather than protein as its main source of nutrition.

In a standard ketogenic diet plan, a high proportion (up to 80%) of your daily calories are derived from fat, while a minimal amount (5%) come from carbohydrates — this is 40-60% lower than the amount of carbohydrates recommended in the average diet.

If you take in a total of 2,000 calories for the day, only a small portion, about 5%, of that should be carbs, including nutritious veggies and fruits.

When you consume this type of diet, it prompts ketosis to occur, which implies that your body has used up all its carbohydrates and must now start burning fat for energy. The main objective of the strict regulations of keto is to make your body utilize an alternate source of energy.

Adopting a diet which includes lots of fat and few carbohydrates can assist in rapid weight loss. Nevertheless, as it is with any dietary journey, the keto lifestyle may not be suitable for everyone and can pose certain difficulties.

Certain outcomes of taking this medication may be advantageous, but there may be some which can be undesirable or even dangerous. It is important to be aware of any potential keto diet side effects before deciding if it is the right choice for you.

1. Keto flu

Keto flu is a real thing. Reducing your carbohydrates drastically and entering a state of ketosis (where your body is burning fat for fuel) may spark an assortment of uncomfortable side effects, including severe headaches, exhaustion, body aches, nausea, and diarrhea.

The adjustment of your system to primarily relying on fat for fuel rather than carbohydrates is what brings about the side effects, according to Kristen Mancinelli, M.S., R.D.N., who has written a book about the Ketogenic Diet. Once your body begins to get used to the alternate energy source (typically within seven to fourteen days), you will experience an improvement in your condition.

2. Fluctuating mood

If you are following a low carbohydrate regimen, you may not be getting the carbohydrates required to produce serotonin, a hormone in the brain that plays a role in managing mood and controlling sleep and appetite. This can have a marked effect on how you are feeling, as highlighted by Laura Iu, a certified dietitian and nutrition therapist, who is also an intuitive eating counselor based in New York City.

3. Initial weight loss 

The keto diet is notorious for delivering a quick initial slim down. That’s because carbs hold on to more water than protein or fat, says Becky Kerkenbush, R.D., a clinical dietitian at 
Watertown Regional Medical Center.
So when you stop eating them, all that extra H2O gets released through urination. As a result, the scale might read a few pounds lower, and you may look a bit leaner.

That first drop might be mostly water weight. Studies imply that the keto diet is advantageous for shedding fat. A research conducted in Italy with nearly 20,000 overweight people revealed that those who adopted a keto diet dropped approximately 12 pounds in 25 days.

Although there are not a lot of investigations looking into if the lost weight will sustain in the long run, scientists note. It can be difficult for many people to remain on track with such an exact eating regimen, and if you go against your diet, the weight can quickly build up again.

4. Constipation

Constipation is a common side effect of low-carb eating plans, including the ketogenic diet.
Severely curbing your carb intake means saying goodbye to high-fiber foods like whole grains, beans, and a large proportion of fruits and vegetables, says
Ginger Hultin, M.S., R.D.N., Seattle-based nutritionist and spokesperson for the Academy of Nutrition and Dietetics.

5. Diarrhea

The combination of your body discharging more liquid plus a possible formula for obstructed pipes creates a potential issue.

To keep the flow going, David Nico, Ph.D., the author of Diet Diagnosis, recommends eating food high in fiber, such as avocado, nuts, limited amounts of non-starchy veggies and berries, as part of a keto-friendly diet. Upping your water intake helps, too.

Consuming items that are high in fat causes the liver to produce bile which assists in the digestion process. Eating a lot of fat, like with the keto diet, means the liver releases more bile which can act as a laxative. This can cause both loose stools and a faster movement of material, which can lead to diarrhea, explains Iu.

6. Bad breath 

When your body goes into ketosis, it will start to produce by-products called ketones. This includes acetone—yes, the same chemical found in nail polish remover, which your body actually naturally makes on its own, according to a
2015 review of research.
“One of the ways ketones are released from the body is through exhaling, and breath usually has a distinct odor that’s different than the common bad breath experienced when there’s a build up of bacteria in the mouth,” says Iu.

7. Intensified cravings 

Cutting out carbs can cause the brain to release a chemical calledneuropeptide-Y (NPY), which tells the body that we need carbs; when we don’t get those carbohydrates our body needs, this chemical builds up and can intensify cravings, which can increase the risk of developing disordered eating patterns like binge eating, says Iu. “It has nothing to do with not having enough ‘will power,’ it’s more to do with the body’s biological response to deprivation,” she says.

8. You’ll need to drink a lot more water
Don’t be surprised if you find yourself parched while you’re on the keto diet. Excreting all that extra water will likely cause a spike in thirst—so make it a point to drink up, Mancinelli advises.
There’s no hard and fast recommendation for how much water you should be having on a keto diet. But in general, aim to drink enough so your
urine is clear or pale yellow. If it’s any darker, bump your intake.

9. Low athletic performance 

Low-carbohydrate diets don’t provide the body with significant amounts of glycogen stored energy, which is the body’s favorite source of power for physical activity. Therefore, your ability to complete exercises, competitive sports, and workout activities will decrease.

A research discovered that those on a four-day ketogenic eating routine performed undeniably more ineffectively on strenuous cycling and running errands contrasted with individuals who went through four days on a high-carb diet.

Side Effects After Discontinuing a Low Carb Diet 

You may experience negative reactions as your body adjusts to going off of your low-carb diet. The following are the most common:

10. Gaining weight

Health professionals warn that low-carb diets cannot be followed for extended periods of time due to their rigid nature. Instead, it’s best done for 30 to 90 days. The difficulty is that a lot of individuals will recover a large portion of the weight they had lost after resuming the consumption of carbohydrates.

You might experience a gain in weight, often as a result of water weight since eating carbs increases the amount of water in your body. The more water you have in your body, the heavier it will be. So it isn’t fat gain or unhealthily gained weight.

It appears that regaining any lost weight is a common problem when going on a fad diet, however it is particularly prevalent when following a low-carb diet. The continual ups and downs in body weight can lead to an unhealthy attitude towards food, eventually resulting in eating disorders.

11. Irritability and fatigue

The fluctuation of blood sugar can lead to fatigue and irritability, particularly when you consume basic carbohydrates and sweets. Many people say that the annoyance they experience when ceasing a low-carb diet is especially severe in the initial three days but that it begins to fade after the seven day period.

12. Hunger

It is possible that you could experience hunger if you are not accustomed to a high-fat diet which would normally make you feel full quickly, due to the lack of carbohydrates. In addition, eating simple carbohydrates or sugar can lead to spikes in blood sugar, making you feel hungry again after only a short period of time.

13. Bloating

Raising the intake of fiber and carbohydrates may cause swelling during the period of adjustment. High bodily water can also appear as bloat. Nevertheless, the situation should improve, and you need to keep drinking fluids to adjust to the climate.

Foods to Eat While on a Low Carb Diet 


Not all fruits contain high levels of carbohydrates. In addition, due to their healthy aspects, these foods can be incorporated into a low-carbohydrate meal plan. Fruit also includes naturally occurring carbs like glucose and fructose, which are less detrimental to your health compared to processed sugar.

Fruit varieties such as berries, watermelon, kiwis, apples, peaches, cherries, and citrus fruits generally have lower amounts of carbohydrates. Veggies are abundant in minerals such as potassium, manganese, and magnesium, while also supplying a healthy dose of antioxidants. In addition, their high fiber content helps to ward off numerous illnesses.

If you are adhering to a low-carb ketogenic diet (eating no more than 20 grams of net carbs per day), it is preferable to pick berries rather than other types of fruit.

Only 1-2 servings of fruit should be consumed daily on a diet that limits carbohydrate intake to 20-50 grams. You can have an abundance of fruits daily when on a low-carbohydrate diet which requires you to consume between 50 and 100 grams of carbohydrates daily.


Vegetables that come from plants that grow above the ground typically contain fewer carbohydrates than those that grow underground. Vegetables contain large amounts of essential nutrients, vitamins, and antioxidants.

Consequently, they are advantageous for managing numerous illnesses, such as high blood pressure. Some of the healthiest foods to consume are tomatoes, peppers, greens, cauliflower, and other types of vegetables.

Poultry, meat and seafood

Poultry and meats that contain little fat are full of protein and have few carbohydrates. Fish that are high in fat contain a lot of omega-3 fatty acids and have few carbohydrates.

These beneficial fats aid your body in combating unhealthy cholesterol. Your low-carb eating plan can include tuna, prawns, salmon, mackerel, and other fattier varieties of fish.


Nuts are a beneficial extract that offer a big quantity of magnesium, potassium, dietary fiber, and antioxidants. In addition, unsalted nuts provide a low-sodium and high-beneficial fat content.

Omega-3 and 6 fatty acids are abundant in them. Low-carb nuts include almonds, cashews, peanuts, and walnuts.

Decreasing your intake of carbs does not mean reducing the amount of necessary nutrition your organism needs to operate as usual. Instead of just going on a low-carb diet, one can benefit their health by consuming the right types of food and planning a balanced diet.


Those with diabetes, as well as individuals utilizing hypertension or glucose-regulating medications, should consult with a doctor prior to initiating a low-carbohydrate diet. When attempting a low-carb diet, one may need to make adjustments to the medications they are taking and should make sure to keep it under close observation.

Folks usually begin a low-carb regimen for temporary weight loss and to maintain their blood sugar levels. Further investigation is called for to find out the lasting effects of embracing this type of eating pattern.

Studies on the consequences of low-carb diets over a lengthy period suggest they may be hazardous, potentially putting one in danger of passing away earlier, developing cardiovascular illness, strokes, and cancer.

Pregnant and breastfeeding moms should probably avoid low-carbohydrate diets. If you are trying to become pregnant, currently pregnant, or nursing, you may want to consider reducing your intake of carbohydrates.

It would not be advisable to go on a low-carbohydrate diet since the energy needs for performing various bodily functions are higher in that situation.


A low-carb diet has both advantages and disadvantages, just as the two sides of a coin. One’s race and ethnicity play a role in their capacity to maintain a dietary regimen.

As an example, it may prove to be more difficult for citizens of Asian subcontinent nations to stick to a low carb diet than those in the western world, who largely base their diet around proteins.

Many people believe that the low-carb diet is beneficial for weight loss. However, there is a possibility of weight regain. It is unlikely that a slight decrease in carbohydrates intake will lead to any discernible adverse reactions.

Significant reduction in carbohydrate consumption could lead to more serious effects, including headaches, exhaustion, and alterations in gastrointestinal habits. Speaking to a knowledgeable nutritionist is the most effective way to learn what diet is best suited for you and your particular needs.

Leave a Reply

Your email address will not be published. Required fields are marked *