The Ketogenic Diet: The Pros, The Cons, And The Risks

The ketogenic or “keto” diet that’s been increasing in popularity ever since carbs went out of style, has some real benefits, and some real risks. Weight loss? Sure. More mental focus? Yes, according to its followers. Severe restrictions, constipation or diarrhea, and bad breath? Yep—that too.

Here we’ll explain how the ketogenic diet came about, how it works (it’s a bit different from other low-carb diets), and the pros, cons, and considerations. By the end of the article you may be inspired to throw your bread out the window and dump your cereal down the drain, or you may decide that keto is not right for you and go have a pasta salad. Either way, here’s what you need to know:

Photo: AdobeStock/Monkey Business
Photo: AdobeStock/Monkey Business

Way Back When…

The ketogenic diet was first designed in the 1920s by doctors at the Mayo Clinic as a treatment for epilepsy. The diet is still recommended for the condition and reduces seizure rate in about half of epileptic patients.

In the 1990s, low-fat diets became popular as Americans were trying to get healthier. The thought was that fat in your food meant fat on your body, which makes sense, but fats were replaced by simple carbohydrates and sugar. So total calories stayed the same or went up, as did the numbers on the bathroom scale.

When the Atkins diet became popular in the early 2000s, cutting carbs seemed counter-cultural. Regardless, a diet that included, and even encouraged, things like butter, bacon, and steak was most welcome.

Because Atkins was effective, at least in the short-term, it led to other iterations of the low-carb diet like the South Beach Diet and the Paleo diet. While all three diets have important differences, they all emphasize consuming fewer carbs, especially the ones we know are bad for us like white breads, sugary treats, and alcohol.

Photo: AdobeStock/happy_lark
Photo: AdobeStock/happy_lark

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Enter Keto

The stage had been set for the ketogenic diet. Adherents claim that the diet has no only allowed them to lose weight, but given them better mental focus, greater energy, and stable blood sugars, which is especially helpful for people with diabetes. The claims are attractive. But first, you have to put in the work:

The ketogenic eating plan

The ketogenic diet is a high-fat, moderate-protein, and low-carbohydrate diet. Depending on your specific plan and where you get your information, your diet should be made up of:

  • Fats: 60 to 80%
  • Protein: 25 to 30%
  • Carbohydrates: 5 to 10%
Photo: AdobeStock/hartphotography
Photo: AdobeStock/hartphotography

In general, someone on the diet will not be consuming more than 30 to 50 grams of carbohydrate a day. The Dietary Guidelines for Americans recommend around 225 to 325 grams of carbohydrates per day for those eating 2,000 calories.

After several days of significantly reducing carbohydrates, your body will be low and have to start burning fat. Glucose (from carbohydrates) is the body’s preferred source of fuel because it’s quick and easy to burn. While glucose is readily available, the body will simply store fat (and excess glucose as fat). However, when glucose stores are low, the body begins to break down fat to use as fuel. The fat breakdown produces ketones, which the body can use for energy instead of glucose. This process is called ketosis, and reaching and maintaining this state is the goal of the ketogenic diet.

Photo: AdobeStock/Saltodemata
Photo: AdobeStock/Saltodemata

Before we go any further, it’s important to note the difference between ketosis and diabetic ketoacidosis. Ketones are acidic, but generally safe at moderate levels. In most of the population, the hormone insulin will tell the body when to stop releasing fatty acids and producing ketones, and ketones won’t go beyond healthy levels. People with type 1 diabetes do not make insulin on their own, and they can reach dangerously high levels of ketones and go into diabetic ketoacidosis, which can be deadly if not treated. In rare cases, those with type 2 diabetes can also go into ketoacidosis.

Those on the ketogenic diet sometimes use ketone testing strips, available from pharmacies, to check their urine for ketones to see if they’ve successfully reached ketosis. But people with diabetes need these testing strips to stay safe, so priority should be given to those who need the strips for medical purposes (a run on ketone test strips in Australia led to severe shortage).

Photo: AdobeStock/abidika
Photo: AdobeStock/abidika

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