This is the original, official international diet bestseller used by celebrities such as Adele, heavyweight champion David Haye, and Pippa Middleton. The science-based program will help you lose seven pounds in seven days while experiencing lasting energy and enjoying the foods you love including chocolate, red wine, strawberries, and more.

Over the past few years, fasting has become a popular diet option. Studies show that fasting—whether through moderate calorie restriction every day or the more severe but less frequent intermittent fasting—can help people lose about thirteen to fourteen pounds in six months and reduce their risk of developing disease.

When we fast, our body’s energy stores activate what is known as sirtuins, or the “skinny gene,” and many positive changes ensue. Fat storage is switched off, and our body stops its normal growth processes and goes into “survival” mode. Fat burning is stimulated and the genes involved in the repair and rejuvenation of our cells are turned on—which all results to weight loss and improved resistance to disease. But if not done correctly, fasting can lead to hunger, irritability, fatigue, and loss of muscle.

Enter Sirtfoods: a newly discovered group of foods that is revolutionizing healthy eating. Ranging from chocolate and red wine to garlic and walnuts, sirtfoods are particularly rich in special nutrients that help us activate the same skinny genes in our bodies that fasting triggers. Nutritionists Aidan Goggins and Glen Matten have created The Sirtfood Diet to help you effectively lose weight and improve your resistance to disease, while still giving you incredible energy and glowing health.