Ketogenic Diet: Which Patients Benefit?

John Watson; Reviewed by: Anya Romanowski, MS, RD


March 20, 2018

In This Article

The Disease-Fighting Diet

When it comes to addressing disease, most diets have a precautionary pitch: Eat better, lose weight, and push back the day you receive an unwanted diagnosis from your doctor. In recent years, the ketogenic diet (KD) has changed this dynamic by being positioned as less preventive and more prescriptive. By committing to this diet, its proponents argue, patients with serious and life-threatening conditions are doing more than practicing healthy eating; they're applying a nonpharmacologic approach that may directly affect their outcomes. In an era defined by soaring drug costs and a back-to-basics whole food movement, it's an idea that's garnering excitement.

"Ketogenic diets have been used for specialized conditions, such as control of epilepsy, for years," explained David S. Ludwig, MD, PhD, founding director of the Optimal Weight for Life (OWL) program at Boston Children's Hospital and a professor of nutrition at Harvard School of Public Health. "However, interest in this approach for obesity, diabetes, and other chronic conditions has burgeoned in the past decade in light of exciting laboratory data and preliminary clinical trials."

In this overview, we take a closer look at what the latest research shows about the value of KD in several conditions.

What Is KD?

The classic KD is composed primarily of fat (80-90%), with the remainder filled in with protein (8%-15%) and, to a minimal degree, carbohydrates (2%-5%).[1] The goal is to mimic the body's state during fasting without impairing its ability for growth. By limiting the amount of carbohydrates and protein metabolized, energy is instead derived from fat within the body or consumed in the diet.[1] As glucose levels decrease, fat-derived ketone bodies begin to take over as the body's main energy source, a metabolic state known as ketosis.[2]

In addition to classic KD, there are three common variations of this diet: a medium-chain triglyceride diet, a modified Atkins diet, and the low-glycemic-index treatment.[3] These give practitioners more variability as they try to offer palatable options to patients by increasing protein, decreasing fat, substituting all but non-starchy vegetable carbohydrates, and other strategies.

Even with a variety of diets to choose from, health concerns remain surrounding their adoption.

"If not done correctly, a ketogenic diet carries important risks, including nutrient deficiencies, hypovolemia, hypokalemia, kidney stones, and gout," said Ludwig. "However, these risks can be minimized with a properly formulated diet."


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