Exploring the Origins: What Was the Original Purpose of Keto?

November 19, 2025 •

4 min read

In 1921, Dr. Russell Wilder of the Mayo Clinic first used the term “ketogenic diet” to describe a nutritional therapy designed for a medical purpose, not weight loss. It was created to mimic the metabolic benefits of fasting, a practice observed for millennia to help control seizures in individuals with epilepsy.

Quick Summary

The ketogenic diet was developed in 1921 to treat intractable epilepsy in children by inducing ketosis, mimicking the effects of fasting to control seizures.

Key Points

Epilepsy Treatment: The original purpose of the keto diet was to medically treat intractable epilepsy, especially in children, back in the 1920s.
Mimicking Fasting: The diet was created to replicate the anti-seizure benefits of therapeutic fasting in a sustainable, long-term eating plan.
Mayo Clinic Origins: Dr. Russell Wilder at the Mayo Clinic coined the term "ketogenic diet" and first implemented it as a therapeutic dietary option for epilepsy in 1920s.
Ketosis Mechanism: By forcing the body to use fat for fuel, the diet produces ketone bodies that can cross into the brain, providing an alternative energy source and helping to stabilize neuronal activity.
Medication Impact: The diet's popularity waned significantly after effective anti-epileptic drugs became available, as medication was often easier for patients to manage.
Modern Shift: While retaining its medical use for specific conditions, the ketogenic diet found a new audience in recent decades as a popular trend for weight loss and general wellness.
Medical vs. Trend: The classic medical ketogenic diet involves strict macronutrient ratios and supervision, differing greatly from the modern, less-regulated weight-loss version.

From Ancient Fasting to Modern Therapy

The story of the ketogenic diet begins not in the 21st-century fitness world, but in ancient medical practices. For centuries, physicians, including those in ancient Greece, noted that fasting could help control epileptic seizures. By the early 1900s, this observation had evolved into more formal therapeutic fasts for epilepsy patients, though seizures often returned after feeding resumed. This led to a search for a more sustainable dietary intervention that could replicate the benefits of fasting permanently.

The Mayo Clinic's Groundbreaking Work

This search culminated in 1921 when Dr. Russell Wilder of the Mayo Clinic and Dr. Rollin Woodyatt independently explored the metabolic changes associated with starvation and high-fat, low-carbohydrate diets. Woodyatt observed that starvation and a fat-rich diet both resulted in the production of water-soluble compounds called ketone bodies. Wilder took this a step further and coined the term "ketogenic diet," proposing it as a treatment for epilepsy.

Expanding Ketogenic Therapy at Johns Hopkins

The ketogenic diet's use quickly spread beyond the Mayo Clinic. At Johns Hopkins Hospital, pediatrician Mynie Gustav Peterman further refined the classic ketogenic diet composition, establishing the strict macronutrient ratios still studied today (typically 4:1 fat to combined protein and carbohydrates). From the 1930s through the 1970s, clinics at Johns Hopkins and other institutions treated hundreds of children with medically resistant epilepsy using this dietary approach, often with significant success.

The Decline and Modern Resurgence

Despite its documented effectiveness, the popularity of the ketogenic diet declined sharply with the introduction of new anticonvulsant drugs in the mid-20th century. For clinicians, prescribing a pill was simpler and easier to manage than supervising a highly restrictive diet. For patients, adherence was often challenging. The diet was largely relegated to a last-resort treatment for drug-resistant cases.

A dramatic revival of interest occurred in the 1990s, largely thanks to Hollywood producer Jim Abrahams. After his young son's intractable epilepsy was successfully treated with the diet, Abrahams founded the Charlie Foundation for Ketogenic Therapies. The foundation helped fund new research and promote awareness, notably through a 1997 television movie starring Meryl Streep, which brought the diet back into the public consciousness. This sparked a resurgence in scientific study and clinical application.

The Mechanism Behind Keto's Neurological Effects

The precise mechanisms by which the ketogenic diet works for neurological conditions are still being studied, but research points to several factors. The core idea is that by drastically limiting carbohydrates, the body is forced to produce and utilize ketone bodies for fuel. These ketone bodies can cross the blood-brain barrier and provide an alternative energy source for the brain. This metabolic shift appears to have several effects that reduce seizure activity:

Enhanced Energy Metabolism: Ketone bodies produce more ATP (energy) than glucose, which may help stabilize neuronal activity and make neurons more resilient to metabolic stress.
Neurotransmitter Modulation: The diet may increase the brain's levels of gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter, while reducing excitatory neurotransmitters like glutamate, creating a more balanced neurological state.
Anti-inflammatory and Antioxidant Effects: Ketone bodies have been shown to have anti-inflammatory and antioxidant properties, which can protect nerve cells.

Comparison: Medical Keto vs. Modern Weight Loss Keto

While the underlying metabolic principle is the same, the execution and context of the historic therapeutic ketogenic diet and the modern weight-loss version differ significantly.


Feature	Classic Therapeutic Ketogenic Diet (1920s)	Modern Weight-Loss Ketogenic Diet (2020s)
Primary Goal	Medically treat drug-resistant epilepsy, primarily in children.	Weight loss, improved metabolic health, and general wellness.
Carbohydrate Intake	Extremely low, often strictly controlled and weighed daily to achieve a specific fat-to-protein/carb ratio (e.g., 4:1).	Very low, typically under 50 grams of net carbs daily, but often less strict and not weighed.
Macronutrient Ratio	Rigid, calculated, and often monitored by a medical team to ensure therapeutic ketosis.	Varies, with fat consumption often prioritized to induce ketosis without strict ratios, and protein intake may be higher.
Professional Supervision	Essential and always medically supervised due to the risk of side effects like hypoglycemia.	Typically not medically supervised; individuals rely on online information and commercial products.
Sustainability	Very difficult to maintain long-term due to extreme restrictions and potential side effects.	Often not sustainable for many people, leading to weight regain after stopping the diet.
Nutrient Consideration	Specialized care ensures adequate protein for growth and proper supplementation to prevent nutritional deficiencies.	Often lacks proper nutritional balance, potentially leading to vitamin and mineral deficiencies.

Conclusion: From Medical Niche to Mainstream Fad

What was the original purpose of keto is a story of medical innovation and the search for alternatives when conventional medicine falls short. The ketogenic diet's roots as a highly specific, medically supervised treatment for severe epilepsy contrast sharply with its modern, popularized application for general weight loss. While its metabolic principles remain constant, the context, adherence, and supervision have evolved dramatically over the last century. Today, it stands as a testament to the fact that a treatment designed for a specific illness can find new, broader applications—though its history reminds us that strict diets, especially for medical purposes, are best undertaken with professional guidance.

The history of the ketogenic diet illustrates a powerful point about how therapeutic interventions can cross over into the public sphere. For more information on the history and therapeutic applications of ketogenic diets, consider visiting The Charlie Foundation for Ketogenic Therapies, an organization dedicated to advancing ketogenic therapies for epilepsy and other neurological disorders.

Frequently Asked Questions

The ketogenic diet was first developed in 1921 at the Mayo Clinic by Dr. Russell Wilder as a medical treatment for epilepsy.

The diet was created specifically to treat children with medically resistant or intractable epilepsy, with the goal of reducing the frequency and severity of seizures.

The diet mimics the metabolic state of fasting, which had been anecdotally observed to help control seizures. It shifts the body's energy source from glucose to fat-derived ketone bodies, which appear to have a stabilizing effect on brain activity.

Observations of the effects of fasting on epilepsy have been recorded since ancient times. By the early 20th century, modern physicians had begun studying the link, leading to the development of the ketogenic diet as a longer-term solution.

Yes. Its widespread use declined in the 1930s and 1940s with the development of new anti-epileptic medications, which were seen as a more convenient treatment option.

The modern revival began in the 1990s, catalyzed by Hollywood producer Jim Abrahams and the Charlie Foundation, which promoted awareness and funded research after the diet successfully treated his son's epilepsy.

No. The classic therapeutic ketogenic diet is a strictly calculated regimen used under medical supervision. The modern weight-loss version is often less restrictive, and lacks the necessary professional guidance, though the core metabolic principle is similar.