I’ve heard a lot of people talking about the ketogenic diet recently. One of my dietitian colleagues suggested I do some research on it and share my findings via this column. Here are the thoughts of a registered dietitian and certified diabetes educator.
First let’s explore what the ketogenic diet is. The ketogenic diet is a diet that is high in fat and low in carbohydrates. The primary objective of the ketogenic diet is to encourage the body to rely on fat instead of carbohydrate for fuel. This process results in something called ketogenesis, where ketones are made from fat for the body to use for energy. Usually, cells rely on a combination of fat and carbohydrate for energy. Some cells can only use carbohydrate for energy.
Now let’s dive in to the pros and cons. I like to end on a good note, so let’s start with the negatives about this diet. One of the big negatives for your health with this type of diet is that your body has to rid itself of the byproducts of ketones via urination. Usually, about half of the weight you lose on this diet is fluid, which comes back (as it should) when you start eating carbohydrates again. The really big issue for health is that the remaining weight you lose is split between fat loss and muscle loss. For most people’s health, the main focus should be on increasing muscle and reducing fat stores. This diet does not achieve that since you lose both fat and muscle. Another problem is that this diet is not sustainable long-term. Think about never eating a carbohydrate food again. That would mean no fruit, no grains, no starches, no milk, and no yogurt. As previously written about, eliminating entire food groups results in a person not being able to get enough of vital nutrients. With the elimination of all of the above foods/groups, one would be missing out on great sources of fiber and many vitamins and minerals. Plus, the research that is out there usually compares a high fat diet to a high carbohydrate diet for a few weeks (usually 10-16 weeks) and in relatively few people. One study published in the American Diabetes Association that followed people on a high fat versus a high carbohydrate diet for one year found no difference in weight or HgbA1c (a marker of blood sugar) after one year.
There are a few positives to this diet. Quick weight loss is one (again, since a large part of the weight lost is fluid, and this is accompanied by quick weight gain when the diet is no longer followed). Encouraging eating plenty of vegetables is another. It may be helpful for people who have seizures.
It is perfectly possible to manage weight, blood sugar, and other health conditions by eating a well-balanced diet that includes all food groups. That is what I, the USDA, the American Diabetes Association, the American Heart Association, and many others recommend. It’s okay to eat what you like to eat. If you enjoy eating something that is healthful for you, go for it! If you know it’s not the healthiest food in the world, try to eat it less often. Moderation in all things remains my motto.
Lynn Grant R.D., L.D., CDE is a Registered Dietitian and Certified Diabetes Educator. She works at Capital Region Medical Center and provides diabetes education and outpatient nutrition counseling by appointment. She also writes a weekly nutrition blog, which you can follow at nutritionnotions.wordpress.com.