Is it safe to be keto while pregnant? This is a valid concern because a mother’s diet greatly impacts the health of the child. We know that the current dietary recommendations for Americans is poor and outdated. Currently, the dietary recommendation for carbohydrate intake during pregnancy is 45-65% of calories. This number, however, was created based on unscientific calculations. Furthermore, studies show fetuses with higher intake of maternal carbohydrates have higher levels of obesity (1). Normal pregnancies tend to naturally fall into low-level ketosis. The 131 Method recommends a moderately lower-carb diet for a portion of the program, so it is possible to safely maintain low-level ketosis during pregnancy, if certain precautions are taken.
A great book for women to understand how REAL food plays into a healthy pregnancy is, “Real Food for Pregnancy,” by Lily Nichols. Her other book, “Real Food for Gestational Diabetes,” is a must-read for any woman with a history of gestational diabetes or diagnosis of gestational diabetes.
Very few research studies can be done on the topic of ketosis and pregnancy in humans because of the nature and research required.There is one old study from 1969 that studied ketones in pregnancy, however, it was greatly flawed, using urine ketones (not a reliable measure) on the day of delivery only (2). Much of the other research done is on women with Type 1 diabetes and diabetic ketoacidosis. Diabetic ketoacidosis is far different than nutritional ketosis. Diabetic ketoacidosis is when someone with Type 1 diabetes has unhealthy toxic levels of both ketones and blood sugars (glucose). Diabetic ketoacidosis and toxic levels of ketones are not recommended, pregnant or not. Diabetic ketoacidosis is the only way to reach a toxic level of ketones in the body.
Is keto during pregnancy safe?
Most studies show that low levels of ketones for a baby are actually be beneficial.Fetuses’ brains receive 30% of their energy from ketones (3). Ketones are used to synthesize cerebral lipids. Babies use ketones for energy. Low levels of ketones produced by a mother are common and important for the growth of the baby. Some experts believe that while pregnant, women produce ketones more easily. If a woman fasts from dinner to breakfast, it’s normal, even when not pregnant, to produce a low level of ketones. If a pregnant woman eats a low carbohydrate diet, it’s also likely her body will produce ketones. In fact, blood ketones are about 3 times higher in an overnight fast during pregnancy compared to non-pregnant women (4). This confirms the theory that ketone production is very natural part of the metabolism of pregnancy. In fact, a keto pregnancy may be occurring without many women noticing. After babies are born, their main source of energy comes from fat in the form of breast milk and colostrum. At least 25% of their energy is from fat in breastmilk (5). Many experts believe the first weeks of a newborn’s life are spent in a state of ketosis as they use their fat energy storage. (6).
On the opposite end of the spectrum, a diet with too many carbohydrates and sugar can be detrimental to a fetus, and the mother. High levels of sugar in a pregnant mother’s diet can lead to extra weight gain, gestational diabetes, excema, asthma and predisposition to ADHD (7). During pregnancy, a woman’s body naturally develops an increase in insulin resistance. Given the risks, following the current dietary recommendations of 45%+ carbohydrates might not be the most sound advice for pregnant women.
So, how many carbs should be consumed?
Consuming a diet with around 16-27% of total calories coming from carbohydrates, or 90-150g per day (with over 2200 calories/day) is a healthy recommendation for pregnancy. This still allows most women to produce low levels of ketones without depriving the fetus of the glucose and nutrients needed for growth. This recommendation aligns with most traditional and ancestral cultures. (7). As with all recommendations, everyone is different, so amounts vary person to person. You must listen to your body.
How does this apply to the 131?
Fasting of any kind is not recommended while pregnant. Outside of a regular overnight fast (during sleep), intermittent fasting and any of the fasting protocols are not recommended. It also means that it’s safest to keep your carbohydrate intake slightly higher than the 5-10% of carbs recommended in Ignite throughout pregnancy. Start slowly, especially if you’re new to low-carb eating.. You can track your total carbohydrate and macronutrient percentages in an app such as My Fitness Pal, and play with the percentages that feel best for you.
Be sure to talk to your doctor about the proper vitamins, minerals and supplements you may require. Lower carb eating is a natural diuretic, so be sure to consume adequate water as well as electrolytes, and consider a daily electrolyte supplement.
In summary, a fetus requires glucose for growth, but it also requires ketones. In excess, both can be dangerous. A keto diet during pregnancy must be modified for the individual but there are benefits. Of course, if you explore a keto diet while pregnant, you’d want to ensure you’re fueling with the most micronutrient dense foods to get aduate vitamins and minerals. Pregnancy is a time to take care of your body while ensuring the safety and growth of baby-to-be. Consult your medical provider about your personal history, medical conditions, and be sure to monitor how you feel and note any symptoms that correlate to changes in your nutrition.
- Chen, Ling-Wei, et all. “Associations of maternal macronutrient intake during pregnancy with infant BMI peak characteristics and childhood BMI.” American Journal of Clinical Nutrition 105.3 (2017): 705-703.
- Churchill, JA, HW Berendes, and J Nemore. “Neuropsychological deficits in children of diabetic mothers.” American Journal of Obstetrics and Gynecology 105.2 (1969): 257.
- Institute of Medicine (US). Panel on Macronutrients, and Institute of Medicine. Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. Dietary Reference Intakes for energy, carbohydrate, fiber, fat, fatty acids, cholesterol, protein and amino acids. Natl Academy Pr, 2005. Pg 275-277.
- Felig, Philip and Vincent Lynch. “Starvation in human pregnancy: hypoglycemia, hyperinsulinemia, and hyperketonemia.” Science 170./3961 (1970): 990-992.
- Bougneres, PF, et al. “Ketone body transport in the human neonate and infant.” Journal of Clinical Investigation 77.1 (1986): 42.
- Cunnane SC, Crawford MA. Survival of the fattest: Fat babies were the key to evolution of the large human brain. Comp Bioch Phys. 2003;Part A 136:17-26
- Nichols L. Real food for pregnancy; the science and wisdom of optimal prenatal nutrition. 2018.