The classic medical ketogenic diet for the management of intractable epilepsy (also called drug-resistant epilepsy) was created in the 1920s at the Mayo Clinic. It became popularized in the 1990s thanks to the launch of the Charlie Foundation and the release of the movie First Do No Harm. With the popularity of the keto diet for weight loss purposes, many people may wonder how it is different from a medical ketogenic diet that is used to manage drug-resistant epilepsy. While both have the same basic premise: low carbohydrates and high fat, there are many distinctions. In today’s post, we’ll describe the keyways that the medical ketogenic diet for the management of epilepsy is different from the mainstream keto diet that is used for weight loss.
Medical Supervision
One major difference between the medical ketogenic diet and the keto diet for weight loss is that the medical ketogenic diet must be designed and monitored by a medical team, usually a neurologist and a ketogenic dietitian (a registered dietitian who is trained to manage medical ketogenic diets for epilepsy). Not only is the medical ketogenic diet typically initiated in the hospital, but it is also monitored by the medical team on a regular basis to look out for side effects, to ensure nutritional needs are being met, and to assess the diet’s effect on seizure control.
Diet Design
One of the key differences between the medical ketogenic diet for epilepsy and the keto diet for weight loss is the way the diets are designed. The classic medical ketogenic diet is designed according to the ketogenic ratio, that is, the ratio of the amount of fat (measured in grams) to the amount of combined carbohydrates and protein (also measured in grams). The exact amount of carbs, fat, and protein allowed on a classic medical ketogenic diet depends on:
- The specific ketogenic ratio selected by the medical team
- The patient’s specific daily calorie requirement
- The amount of protein required to sustain the patient’s specific goal body mass
Therefore, no two patients on a medical ketogenic diet will have the exact same daily carb, protein, and fat requirements. In comparison, the keto diet for weight loss typically limits carbohydrates to a given amount or aims for a certain percentage of calories coming from carbs, protein, and fats. If you were to compare the two diets according to the number of daily carbs and protein allowed, medical ketogenic diets will typically be much lower in carbs and protein, and much higher in fat. Note that there are less strict variations of the classic medical ketogenic diet, such as the modified ketogenic diet, but even these versions of medical ketogenic diets will be much lower in carbs and higher in fat compared to a keto diet for weight loss.
Protein Restriction
Another difference between the two diets is that the classic medical ketogenic diet restricts protein in addition to carbohydrates. As described above, the amount of protein allowed in the medical ketogenic diet depends on the patient’s goal body mass. In other words, they are allowed just enough protein to sustain their body’s muscle mass but no extra. A keto diet for weight loss typically focuses more on limiting carbohydrates, with less restriction to protein intake.
Diet Initiation
Unlike the keto diet for weight loss, the medical ketogenic diet for epilepsy is generally initiated in the hospital under close medical supervision. Because of the very strict limitation of carbohydrates and protein, the level of ketosis reached on the medical ketogenic diet is much higher compared to a keto diet for weight loss. Therefore, it is essential that a medical ketogenic diet is initiated under medical supervision:
- To ensure that the patient tolerates the selected ketogenic ratio
- To monitor for and treat potential side effects like low blood glucose or vomiting
- To allow the medical team to adjust the diet as needed
This hospital time is also used to train the patient or their caregivers on how to manage the diet once they go home.
Precision of Food Measurement
Another difference between the two diets is the precision with which foods must be measured. On the classic medical ketogenic diet, all foods and drinks must be measured on a gram scale. For example, a meal may call for 29 grams of chicken breast, 50 grams of mayonnaise, etc. Every single bite of the meal must be consumed to ensure that the ketogenic ratio of the meal is accurate. With a keto diet for weight loss, foods can typically be measured with household measurements like cups, ounces, and tablespoons, and there is less concern about finishing the entire meal.
Sticking to the Diet
For patients following a medical ketogenic diet for epilepsy management, breaking the diet, even just a bite, can result in breakthrough seizures. Therefore, having a “cheat meal” or taking a week off for the holidays is simply not an option. Individuals following a keto diet for weight loss may lose weight-loss progress if they fall off the diet for a while, but the consequences are not so serious.
Accounting for Medications & Non-Food Products
With the medical ketogenic diet, the carbohydrate allowance is so specific that trace amounts of carbohydrates from medications need to be accounted for. Typically, when a patient starts the medical ketogenic diet, they are switched to variations of their anti-seizure medications with lower carb amounts (for example, switching from liquid form to tablet form). If there are still carbohydrates coming from medications, the carbohydrate allowance from foods will have to be adjusted to account for them. Oftentimes, the medical ketogenic diet team will recommend specific brands of self-care products that are lower or without carbohydrates (yes, the body can absorb trace amounts of carbs through the skin!). This may be especially important for items that go in the mouth (like toothpaste) or that are applied to large areas of the skin (like moisturizer or sunscreen). Individuals following a keto diet for weight loss generally don’t have to be this precise or careful about trace carbohydrates.
Length of Time
People who follow a keto diet for weight loss may follow the diet for a certain amount of time to lose weight or they may follow a keto lifestyle permanently as a method to maintain weight. On the other hand, patients on a medical ketogenic diet for epilepsy management will usually follow the diet for a specific period. In most cases, if a patient’s seizures are controlled on the medical ketogenic diet for 1 to 2 years, the medical team will recommend weaning off the diet hoping that they can come off the diet and maintain seizure control. However, with certain genetic conditions, like Glut-1 Deficiency Syndrome or Pyruvate Dehydrogenase Deficiency, the medical ketogenic diet must be maintained for longer periods of time or even for lifelong.
For more information on the medical ketogenic diet for epilepsy, visit myketocal.com/ketogenic-diets-for-epilepsy/
Brought to you by Nutricia North America. Always consult with your ketogenic clinician prior to making any changes to your ketogenic diet or condition management.
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