Why People Lose Weight on the Keto Diet

The ketogenic diet — commonly called the keto diet — has become one of the most talked-about nutrition strategies for weight loss and metabolic health. Originally developed as a medical diet nearly a century ago, keto is now widely used for fat loss, blood sugar control, and improved energy levels.

However, despite its popularity, many people still misunderstand how the ketogenic diet works, who it is suitable for, and how to follow it correctly.

In this evidence-based guide, I’ll explain what the ketogenic diet is, how ketosis works, potential health benefits, possible risks, and practical tips for getting started. I’ll also share insights from nutrition researchers and medical experts to help you make an informed decision.

What Is the Ketogenic Diet?

The ketogenic diet is a low-carbohydrate, high-fat eating pattern designed to shift the body’s metabolism away from carbohydrates and toward fat as its primary source of energy.

Typically, macronutrients on keto are distributed as follows:

• 60–75% of calories from fat
• 20–30% from protein
• 5–10% from carbohydrates

For most people, this means consuming 20–50 grams of carbohydrates per day.

Foods commonly eaten on keto include:

• meat and poultry
• fatty fish
• eggs
• cheese and full-fat dairy
• avocados
• nuts and seeds
• olive oil and coconut oil
• low-carb vegetables.

High-carbohydrate foods such as bread, rice, pasta, sugar, and most desserts are restricted.

According to low-carbohydrate nutrition researcher Eric Westman:

“When carbohydrate intake drops low enough, the body switches to burning fat as its primary fuel source. That metabolic shift is what defines ketosis.”