Low Carbohydrate Diet During Lactation
by Anne Eglash MD, IBCLC, FABM
The ketogenic diet is a weight loss strategy involving a diet that is high in fat, adequate in protein, and very low in carbohydrates. By eating low carbs, the body is forced to break down body fat for energy, causing a rise in blood and urinary ketones. If the blood ketones become too high, the body’s blood pH becomes too low (acidotic), which is life threatening. This condition is called ketoacidosis, with symptoms including nausea, vomiting, abdominal pain, and diarrhea. Treatment includes hospitalization for intravenous fluids, carbohydrates, a correction of the acidosis and electrolyte imbalances.
The average non-lactating individual on a ketogenic diet would rarely reach a high enough level of blood ketones to become dangerously acidotic.
Lactating women are at higher risk for ketoacidosis as compared to non-lactating women because of the energy expenditure required by lactation. If breastfeeding women don’t consume sufficient carbohydrates, they will need to break down more fat for energy, causing higher blood ketones, as compared to women who are not lactating.
This condition is well known among dairy cows, and is called bovine ketosis.
- Bariatric surgery during lactation
- Starvation during lactation due to abdominal pain
- A vegan diet during lactation
- Frequent skipping of meals while on a high protein low carb diet
- Gastroenteritis in the setting of a low carb diet
- A urinary tract infection in the setting of a weight loss reduction diet
See the Answer
The ketogenic diet (KD) is a high-fat, adequate-protein, and low-carbohydrate diet that leads to nutritional ketosis and weight loss. It is known to induce ketosis but is not an established cause of clinically significant ketoacidosis. Lactation ketoacidosis is well established in bovine literature but remains a rare phenomenon in humans. Here we present a life-threatening case of severe ketoacidosis in a nondiabetic lactating mother on a strict ketogenic diet. We review the available case reports of lactation ketoacidosis in humans and the mechanisms thereof. Although ketogenic diet has been shown to be safe in nonpregnant individuals, the safety of this diet in lactating mothers is not known. Health professionals and mothers should be made aware of the potential risk associated with a strict ketogenic diet when combined with lactation. Prompt diagnosis and immediate treatment cannot be overemphasized. To our knowledge, this is the first reported case of life-threatening lactation ketoacidosis associated with ketogenic diet while consuming an adequate number of calories per day.
A vegan diet is not, by definition, low carbohydrate.
Lactating mothers frequently ask me about whether a low carb diet is safe during lactation, because they have used this strategy successfully in the past, and lactating women often look for advice on weight loss. Based on the cases in the literature, it would seem wise to advise breastfeeding mothers to avoid a strict low carb diet, particularly in situations of very high energy demand, such as if she is exercising heavily, donating extra milk, or nursing multiples. Further, some of the case reports involve lactating mothers who are ill, so breastfeeding mothers following a low carb diet should be advised to consume carbs in the event that she is ill, such as when experiencing a viral or bacterial infection.
We have created a breastfeeding education handout on Low Carb Diets During Lactation.