The ketogenic diet is a high-fat, low-carbohydrate diet used to treat intractable epilepsy. The diet has been used as far back as biblical times, although it became a medically recognized therapy for epilepsy in 1921. The ketogenic diet became increasingly popular in the 1990s with media coverage and the movie “First Do No Harm,” starring Meryl Streep. The diet has well-documented side effects, but years of practice with it have allowed practitioners to improve the treatment, reduce side effects and improve outcomes for those on the diet. Constipation is the most common side effect of the ketogenic diet.
A specialized dietitian calculates the ketogenic diet based on individual needs to provide a precise ratio of fat to carbohydrate and protein. The diet is extremely low in carbs, eliminating all the fiber-rich grains and severely limiting the portions of fruits and vegetables. The unusual balance of fat and carbohydrates decreases your fiber intake drastically, placing you at high risk of constipation. When planning your ketogenic meals with your dietitian, choose high-fiber vegetables in the meal plans, such as asparagus, cucumbers, green peppers and squash. You may also eat 25 grams of lettuce per day as a free food to increase your fiber intake.
Maintaining Adequate Hydration
Historically, water has been restricted on the ketogenic diet; this is no longer common practice. Ensuring that you are adequately hydrated is another strategy to reduce constipation. If you are going more than three days between bowel movements, you should talk with your medical team about increasing your fluid intake.
Including Avocado and MCT Oil
Another diet modification to improve constipation is to adjust your meal plans to include MCT -- medium-chain triglyceride -- oil or avocado. Both MCT oil and avocados have a natural laxative effect. MCT oil can be prescribed by your diet team or purchased over the counter. It is important to start slow with MCT oil, as high doses may cause stomach discomfort. Discuss any diet changes or added supplements with your nutrition team.
If diet adjustments do not improve your bowel pattern, you may need to take further action. Discuss with your diet team other alternatives, such as carbohydrate-free laxatives or stool softeners. A few of the common laxatives used with the ketogenic diet are polyethylene glycol 3350, magnesium hydroxide and mineral oil. If needed, a glycerin suppository may be used as well.
- Ketogenic Diet Parents Guide; Beth Zupec-Kania, RD, CD
- Building Block for Life: Multidisciplinary Management of the Ketogenic Diet; Beth Zupec-Kania, RD, CD
- Epilepsy Foundation: Ketogenic Diet