Does it really work for weight loss?

Yes — but that answer comes with a qualifier. It takes two to three weeks on the diet to start fat burning (ketosis) in the body. So, don't expect instant results. Some studies have shown that adhering to low- or very-low-carbohydrate ketogenic diets helps people lose weight. However, long term there is little difference between a ketogenic diet and a higher carbohydrate diet.

Ewoldt adds a cautionary note: "This is a very restrictive diet that's tough to follow. The average person is not going to keep doing this long term. Also, because the saturated fat content is high, coupled with limited amounts of fruits, vegetables and whole grains, it is not optimal for health."