The Ultimate Keto Guide

The popularity of the high-fat, low-carb keto diet for weight loss has skyrocketed. But some underlying mechanisms and other benefits don’t get much attention and aren’t widely understood. Here’s what you need to know.

- Vera Tweed

My body weight has been the same since I was 20— never changes,” says Laurie Steelsmith, ND, a naturopath in Hawaii and author of Growing Younger Every Day. She decided to go on a keto diet not to lose weight, but to experience its eff ects. “After about 3 weeks, I felt fantastic, I had so much energy, and kept going,” she says. After following the diet for two months, Steelsmith started modifying it in a way that maintains improvements.

“I no longer have low blood sugar—ever,” which had been a problem before keto, says Steelsmith. “My tendency was not to eat because I get busy, so I got ‘hangry,’ and then I got irritable, and then I felt crummy,” she recalls. But that cycle is gone. One day after breakfast, she went on a six-hour hike up a mountain. Afterward, she knew it was time to eat but wasn’t very hungry, still had plenty of energy, and mentally felt on top of her game. Before keto, she would have been hungry, and likely hangry, long before the end of the hike.

THE KETO THEORY

The keto diet changes metabolism by shifting the human body’s fuel source from blood glucose to ketones, chemicals the liver makes when fat is burned to generate energy. A perfectly healthy human body could switch from one fuel to the other as needed, much like a hybrid car that uses either gas or electrical power. However, the large amount of carbohydrates that most people eat has broken that switch, blocking fat from being used as an energy source. The keto diet forces the switch to turn on.