Evidence Based

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

Susan Adeosun, MD

Published at 01:15

Kathy Shattler, PhD

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.

Pregnant women often have concerns about the safety and long-term effects of adopting the keto diet. Below, we examine the safety of several ketogenic practices and look at the foundations of the ketogenic diet, as well as any possible drawbacks.

Nutrition During Pregnancy

  • Pregnant women have increased nutritional needs, particularly for carbohydrates, which are crucial for fetal development and preventing complications.
  • Following a keto diet while pregnant may result in nutritional deficiencies, which can negatively affect 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.
  • There is not enough data 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, also referred to as the ketogenic diet, is a diet plan that focuses on limiting carbohydrates and opting for high-fat food so the body enters a state of ketosis. Ketosis is when fat replaces carbohydrates as the body’s main fuel.

This diet’s key principles are:

  • Low carbohydrates: Consuming only 20-50 grams of carbohydrates per day.
  • 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 to use as 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

On a keto diet, fruit, vegetable, and whole grain consumption is lower, so there is a lower fiber intake. This can affect stool bulk and lead to constipation. It can be very uncomfortable and even cause complications during pregnancy.

Additionally, the keto diet can cause something called keto flu. 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 medical condition characterized by high levels of ketones in the blood, which makes it more acidic. Pregnant women are more vulnerable to this complication because of their heightened likelihood of entering ketosis and experiencing dehydration.

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.

Several studies on mice suggest that ketone exposure, through a ketogenic diet or other means, can lead to alterations in embryo development. Meaning, possible birth defects. But to determine the relevance of these findings to human pregnancy, further research is needed. At present, there is simply not enough data to answer concretely.

Also, healthy weight gain during pregnancy is very important. A keto diet’s restrictive nature might lead to insufficient weight gain, and negatively impact fetal growth. So, the best thing to do is consult your healthcare provider about any changes to your diet.

Potential Benefit of The Keto Diet

Nonetheless, there are some points on the bright side:

Managing Epilepsy

A study in 2017 suggested that the keto diet might help control epileptic symptoms in pregnant women. This is significant because uncontrolled seizures during pregnancy can pose serious risks to both the mother and the baby, such as 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

A study discovered that when mice offspring were fed a keto diet, their sociability improved and their depression-like symptoms decreased. 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 there might be a chance of nutrient deficiencies, birth defects, or anxiety and depression.

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. Going keto while pregnant might seem fantastic, but to know if it is truly appropriate, you should reach out to a healthcare professional.

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 Aeosun has over five years of experience in public health and preventative medicine. She’s a firm believer in Dutch philosopher Desiderius Erasmus’s phrase, “Prevention is better than cure.” With her expertise and a strong love for writing, Susan has published several health articles on blogs, websites, and peer-reviewed 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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