INDIANAPOLIS (WISH) — A new diet on the rise guarantees a quick weight loss. One local expert says the Sirtfood Diet is too good to be true.

Not only does the diet promise to lose seven pounds in seven days, but recommends the consumption of just 1,000 calories a day.

The diet encourages vegetables, fruits, lean meats, red wine, cocoa and coffee, some of which could be pretty enticing and easy to see why it’s so popular.

The idea started in the United Kingdom and celebrities like Adele are promoting this diet.

Registered dietitian Kate Hake questions some of the science behind the diets “Skinny Gene” claim and is cautious that this kind of diet might not be sustainable long-term.

“From an energy standpoint, anytime we restrict calories like that, you are going to feel fatigued and low blood sugar,” IU Health nutritionist Katie Hake said. “You run the risk too, if you’re exercising, that you could pass out. That’s just not enough energy to sustain you throughout the day. But also when we’re cutting out food groups, we’re cutting out nutrients and things our body needs that you can’t replicate from a juice.”

The diet’s website says benefits include a long, healthy disease-free life, more energy and long-term weight loss success. It also says the diet decreases the chances of severe fasting or acute hunger.

Hake says if something out there is promoting to cut back and promising a quick fix, chances are it’s not sustainable and may leave you more frustrated and not in a healthier place than before.