Evidence Based

Keto While Pregnant: Is It Safe Or Are There Risks?

Susan Adeosun, Dr.

Published at 01:19

Kathy Shattler, MS, RDN

Medical reviewer

Keto diets while pregnant may be risky. Photo: Prostock-studio/shutterstock

Pregnancy is a sensitive time for the expectant mother. Both she and the healthcare system are often heightened in their focus on maternal health and well-being. It is also an important period when a pregnant woman’s diet needs to be health-focused. 

Pregnant women have increased nutritional needs, particularly for carbohydrates, which are important for fetal development and preventing complications. The ketogenic diet is currently popular for its potential health benefits, and you might have heard it can help manage your weight gain.

Expectant mothers often wonder about the safety and implications of following the keto diet while pregnant. In this article, we explore the safety of various keto practices. We will also examine the fundamentals of the keto diet and its potential risks.

Nutrition During Pregnancy

  • Pregnant women have increased nutritional needs, particularly for carbohydrates, which are crucial for fetal development and preventing complications.
  • Adhering to a keto diet during pregnancy may lead to nutritional deficiencies, which can negatively impact both the mother and the fetus.
  • Pregnant women considering a keto diet should consult with healthcare providers to ensure they are meeting all nutritional requirements and to discuss potential risks.
  • A balanced diet rich in a variety of nutrients is generally recommended for pregnant women to support both their health and the baby’s development.
  • Data is insufficient to determine the safe use of keto diets during pregnancy.

What Is a Keto Diet?

What Is a Keto Diet
What Is a Keto Diet? Photo: Tatevosian Yana/shutterstock

The keto diet is short for the ketogenic diet. It is a popular diet plan that consists of a high-fat, low-carbohydrate eating plan designed to bring the body into a state of ketosis. Ketosis is a metabolic state in which fat provides most of the fuel for the body instead of the usual carbohydrates. 

The diet is quite popular for its potential benefits in weight loss, improved energy levels, and certain health conditions. The key principles of the keto diet include:

  • Low carbohydrates: Typically, the diet involves consuming only 20-50 grams of carbohydrates per day, nothing greater than 50 grams of carbohydrates.
  • High fat: About 70-80% of daily calories come from fats.
  • Moderate protein: Protein intake is moderate, making up about 20-25% of daily calories.

When carbohydrate intake is significantly reduced, the body depletes its stored glucose (glycogen) and starts breaking down fat into ketones in the liver. Then, this becomes the primary energy source.

Risks of Keto During Pregnancy

Nutrient Deficiencies

Pregnant women need many nutrients to have a healthy pregnancy. Due to the restrictive nature of the keto diet, essential nutrients such as folate, iron, calcium, magnesium, fiber, vitamin D, and omega-3 fatty acids may be insufficient. 

This means that you limit the intake of healthy foods during pregnancy, such as fruits,  starchy vegetables, grains, and dairy. Folate deficiency, for instance, increases the risk of neural tube defects, while inadequate calcium and vitamin D can impact fetal bone development and maternal bone health.

Constipation

The ketogenic diet typically involves consuming fewer fruits, vegetables, and whole grains, which are primary dietary fiber sources. Low fiber intake can lead to decreased stool bulk and constipation, which can cause significant discomfort and complications during pregnancy. 

Additionally, the keto diet can cause something called keto flu The keto flu is a common side effect that women may experience when starting a ketogenic diet. It causes a range of symptoms that result from the body’s adaptation to a new energy source: ketones instead of glucose. 

For pregnant women, these symptoms can pose additional concerns. They can increase pregnancy-related nausea and fatigue.

Ketoacidosis

For some pregnant women, the reason for starting a keto diet is to manage weight. However, extended fasting paired with a ketogenic diet has been linked to the development of ketoacidosis, a severe medical condition. Ketoacidosis is a serious medical condition characterized by high levels of ketones in the blood, which makes it more acidic. Pregnant women may face an elevated risk of this complication due to the heightened likelihood of entering ketosis and experiencing dehydration when compared to the general population.

Are Keto Diets Safe During Pregnancy?

The safety of the ketogenic diet during pregnancy is a topic of concern due to the unique nutritional needs of pregnant women and the developing fetus. Thus, the keto diet, which is high in fats and low in carbohydrates, can potentially pose several risks during pregnancy. The purpose of using the keto diet is to lose weight, and one does not want to lose weight during pregnancy.

For one, carbohydrates provide glucose, a primary energy source for the developing fetus, especially for brain development. When this is reduced significantly, there might be concerns about proper development. An old animal study showed that pregnant mice fed a keto diet gave birth to baby mice with smaller brains than typical.

Perhaps the most important consideration for safety is the possibility of birth defects. Several studies conducted on mice have observed that exposure to ketones, either through a ketogenic diet or other means, can lead to alterations in embryo development.

These findings raise concerns about the potential for ketones to induce birth defects. However, further research is needed to fully understand the mechanisms behind these effects and to determine the relevance of these findings to human pregnancy. Currently, the data is insufficient to determine the safety of using any form of the keto diet during pregnancy.

Also, healthy weight gain during pregnancy is essential. And so, the restrictive nature of the keto diet might lead to insufficient weight gain, which can negatively impact fetal growth. The best thing to do is consult your healthcare provider about any changes to your diet.

Potential Benefit of The Keto Diet

On the other hand, there are some benefits to the keto diet. Here are some of the researched benefits of the keto diet:

Managing Epilepsy

For example, it has been shown to help treat epilepsy. Managing epilepsy can be particularly challenging due to the need to balance effective seizure control with the safety of the developing fetus. 

A 2017 case study suggested that the keto diet might help control epileptic symptoms in pregnant women. This finding is significant because uncontrolled seizures during pregnancy can pose serious risks to both the mother and the baby, including injury from seizures, preterm labor, and developmental issues for the baby. It may be worth noting that the baby born to the epileptic mom treated with the keto diet in the case study had congenital deformities of the ears.

Treating Diabetes

Another potential benefit of the keto diet is in the event of diabetes. A 2014 study demonstrated that a ketogenic diet can help manage or prevent certain types of diabetes. However, during pregnancy, you don’t need to adopt a keto diet to reduce your risk of gestational diabetes. 

Anxiety And Depression

Another potential benefit of the keto diet is better mental health. A study discovered that exposure to a ketogenic diet boosted sociability and lessened depression-like symptoms in the offspring of mice fed with such a diet. 

This indicates a potential positive impact of ketone exposure on neurodevelopment. However, it’s crucial to bear in mind that these studies were conducted on mice.

Conclusion

Eating keto while pregnant might seem like a great idea, but it is always helpful to reach out to a healthcare expert to know if it is right for you and some risks involved. Research shows that there might be a chance of nutrient deficiencies, birth defects, or anxiety and depression. There is also insufficient evidence of its safety in pregnancy, so following a keto plan may be risky.

Instead of going straight on a diet, it is better to simply eat a healthy diet filled with carbs, rich in healthy fats, proteins, fiber, fresh fruits, and vegetables, which is a safer and more balanced approach.

Frequently Asked Questions

What is ketosis?

Ketosis is a metabolic state where the body burns fat for fuel instead of carbohydrates, producing ketones as a byproduct. This occurs when carb intake is significantly reduced, forcing the body to use fat for energy.

Can I eat fruits on the keto diet?

Most fruits are high in carbs and should be avoided. However, small portions of low-carb fruits like berries (strawberries, raspberries, blackberries) are allowed in moderation.

What are the common side effects of the keto diet?

Initial side effects, known as keto flu, include headache, fatigue, irritability, and nausea. These typically subside within a week as the body adjusts to ketosis. Staying hydrated and maintaining electrolyte balance can help.

Is the keto diet safe for everyone?

The keto diet is not suitable for everyone, especially those with kidney issues, liver conditions, or pancreatitis. Pregnant or breastfeeding women and individuals on certain medications should consult a healthcare professional before starting the diet.

Is the keto diet safe during pregnancy?

The keto diet’s safety during pregnancy is uncertain. It’s crucial to consult a healthcare professional before starting the diet, as nutritional needs during pregnancy are specific and critical for both mother and baby’s health.

Dr Susan Adeosun (MPH, MD) is a Medical Doctor and Public Health enthusiast. She has over five years’ worth of experience in public health and preventive medicine and is a firm believer in the famous phrase by Dutch philosopher Desiderius Erasmus, “prevention is better than cure.” Her journey through public health, combined with her love for writing, has resulted in the publication of several health articles on various blogs, websites, and peer review journals.

Resources

MANA adheres to strict sourcing guidelines, avoids most tertiary sources, and uses only professional resources updated to contain accurate and current information. We majorly rely on peer-reviewed studies, academic research from reputable medical associations. For more information regarding our editorial process, please refer to the provided resources.

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