Is the Ketogenic Diet Safe
Keto Diet

Is the Ketogenic Diet Safe?

You may have heard that weight loss with a ketogenic diet is fast, and some people have even lost more than a dozen pounds in a week. However, we are often told that losing weight too quickly is bad for our bodies. So is the ketogenic diet safe?

What is a Ketogenic Diet?

In the world of diet and weight loss, the most famous low-carb diets such as the Atkins diet, the Mediterranean diet, and the Primal diet have been favored by people around the world who promote healthy weight loss.

What these low-carb diets have in common is that they have very few carbohydrates and a relatively high percentage of protein and good fats. They are sometimes referred to as “ketogenic” or “keto” diets. But they are not the same as a true ketogenic diet.

Compared to other low-carb diets that focus on protein, ketogenic diets can be 75-80% fat-based. Carbohydrates must be less than 5% or no more than 20 grams per day.

The ketogenic diet was first used in the medical field to help reduce the frequency of seizures in children. Although it has also been tried for weight loss, only short-term studies have been conducted. Kathy McManus, chair of the Department of Nutrition at Harvard-affiliated Brigham and Women’s Hospital, warns that we are not certain of the effectiveness and safety of long-term application of the ketogenic diet.

How the Ketogenic Diet Works?

The carbohydrates we eat each day are converted into glucose, which transforms in the body in three forms.

  1. Oxidation for energy: Used as fuel to provide energy to the body
  2. Into glycogen: Stored in the liver and muscles to be used when needed.
  3. Transformed into fat: Into fat cells to be stored for later use.

And when carbohydrate intake is too low to provide enough glucose for energy and the spare glycogen is all consumed, the body has to rely on other energy sources to survive.

The ketogenic diet provides just the right amount of fat to become the perfect substitute. Fats are broken down in the body into the following two forms that enter the liver.

  1. Fatty Acids: Are directly converted into ketone bodies
  2. Glycerol: Undergoes a process of gluconeogenesis and is converted into sugar

Both of these forms provide energy to the body and brain. After a 3-4 day adaptation period, the body will transition from using glucose as fuel to using fat as an energy source. At the same time, your body’s original stored fat cells are mobilized and fat burning officially begins.

Ketogenic Diet Improve Health

Does the Ketogenic Diet Improve Health?

Besides treating epilepsy in children, the other most favored effect of the ketogenic diet is, of course, weight loss. Although the medical community has not yet reached a definitive conclusion on the effectiveness and safety of this method in the long term, its effectiveness in reducing weight and improving insulin sensitivity in the short term is not in question.

Studies have shown that the ketogenic diet is safe for 2-6 months, or can be extended to about 2 years with medical guidance and monitoring. According to a 2017 review published in the journal Nutrients, limiting carbohydrate intake can be effective in preventing metabolic syndrome.

A high percentage of good fats and a moderate amount of protein are the basic requirements of a ketogenic diet, so it significantly increases satiety and reduces levels of the hunger hormone (Ghrelin). With a reduced appetite and less food, you will of course lose weight.

Obesity is a major risk factor for insulin resistance and type 2 diabetes, and a reduction in body fat (especially visceral fat) will lead to an increase in overall health.

However, this article is to remind you that there is a dark side to the ketogenic diet.

Risk Factors of the Ketogenic Diet

Your body has long since adapted to a high-carb diet, and it’s important to be clear about the risks of doing so before making a complete change to your diet.

These risk factors include:

1. Possible effects on the liver and kidneys

Compared to a regular low-carb diet (such as the Mediterranean diet), the ketogenic diet is higher in both lipid-proof and protein content. Some of the fat in the breakdown process will be converted to fatty acids and enter the liver in the form of ketones. The high fat intake increases the burden on the liver.

Protein in the process of being broken down into amino acids will produce nitrogenous wastes, such as urea, which need to be metabolized by the kidneys. So eating too much protein can also increase the burden on the kidneys.

However, these two risks do not need to be overly concern for healthy people. In the case of people with liver and kidney problems, special care is needed.

2. Nutrient deficiency

Restricting carbohydrates means including cereals, starchy vegetables, and fruits with high fructose content is restricted. As a result, you may be at risk of micronutrient deficiencies, including selenium, magnesium, phosphorus, and vitamins B and C.

The remedy is to supplement these micronutrients from protein and meat and seafood from poultry and livestock whenever possible. You can also get these nutrients by taking nutritional supplements.

3. Keto flu

When you first start a ketogenic diet, your body goes through the process of changing from sugar metabolism to fat metabolism. For most people, this series of changes will cause varying degrees of adverse reactions that we call keto flu.

Symptoms include, among others:

  • Nausea
  • Vomiting
  • Diarrhea
  • Constipation
  • Headache
  • Dizziness
  • Weakness
  • Bad breath
  • Hair loss
  • Emotional instability
  • Muscle cramps
  • Muscle aches and pains
  • Difficulty sleeping
  • Craving for sweets
  • Poor concentration
  • Irregular menstruation
  • A few people get the keto rash

But generally, these uncomfortable symptoms will largely subside within a few days or weeks as your body adjusts to the new metabolic pattern.

Who Isn’t Suitable for the Ketogenic Diet?

Although the ketogenic diet has many benefits, especially since it has taken the world by storm in recent years and has helped countless people lose weight. But it isn’t for everyone. If you have any of these health problems, it’s best not to risk trying it, or be sure to do so under medical supervision:

1. Suffering from type 1 diabetes

These patients need to rely on insulin, and the ketogenic diet will also lower blood sugar levels, and the two working together can lead to dangerously low blood sugar.

2. Gallbladder removal

More fat is eaten on a ketogenic diet. The bile secreted by the gallbladder is what helps digest fat, and if this organ is missing, it will be difficult for the body to digest and absorb large amounts of fat.

3. Having multiple sclerosis (MS)

This is a common disease of central nervous demyelination. People with this disease are advised to avoid a ketogenic diet as much as possible. Although some studies have shown that a short-term ketogenic diet is safe for people with MS, it still needs to be done under the specific guidance of a doctor or dietitian.

4. Have thyroid problems

To date, the effects of the ketogenic diet on the thyroid gland remain highly controversial. If you have such problems, such as hyperthyroidism or hypothyroidism, it is best to listen to your doctor’s opinion before considering a ketogenic diet.

5. Have liver or kidney problems

As explained in the previous text, the ketogenic diet may increase the burden on the liver and kidneys. If you have abnormal liver and kidney function, the ketogenic diet is not suitable.

6. Pregnancy and breastfeeding

Ensuring comprehensive nutrition is the most important thing during this period, so for the health of yourself and your baby, don’t try the ketogenic diet for now.


If you ask, is the ketogenic diet safe? The answer is that it is safe in the short term, and this has been confirmed by scientific studies. However, the long-term safety beyond one year is not conclusive, especially since its potential risk factors still cannot be ignored.

If you are in good health and do not have any of the health problems mentioned above, you can try this diet for a short period (2-6 months). Its benefits, in addition to rapid weight loss, include prevention of insulin resistance, a possible reversal of type 2 diabetes, reduced chances of heart disease, cancer, and fewer episodes of epilepsy.