The theory behind the sirtfood diet is that sirtuins, a group of proteins, are thought to play a role in metabolism, muscle growth, ageing and more, by activating the SIRT1 gene, which is also known as the “skinny gene”.

To achieve weight loss, however, the skinny gene needs to be triggered by food and drinks that are high in sirtuin activators. These include red wine, cocoa, green vegetables, blueberries, strawberries, lovage, buckwheat, green tea, turmeric, onion, parsley and olive oil.

Moreover, these foods need to be consumed in a span of two phases over a three-week period, with phase one consisting of seven days, which is further separated into two sub-phases.

For the first three days of phase one, one consumes no more than 1,000 calories per day, which consists of three sirtfood green juices made with lovage, green tea and/or buckwheat, and one meal with sirtfoods. For the remaining four days, one eats no more than 1,500 calories, with two green juices and two sirtfood-rich meals each day.

Phase two involves a 14-day maintenance period where one consumes three sirtfood-rich meals with one green juice daily.

Once the three-week diet is completed, one can repeat the cycle to lose more weight, if they wish.

The verdict

From a registered dietitian’s perspective, this diet highlights the inclusion of vegetables and fruits, which people generally do not eat enough of. Aside from this positive element, the weight loss promises, sadly, seem unrealistic.

Regardless of the type of dieting programme one follows, weight loss is inevitable when one expends more energy than consumed. In this case, one’s body is in an energy deficit state when they are placed on a restrictive, low-caloric diet, when they likely need more calories to maintain their basal metabolism.

Weight loss is also expected when one is restricted to eating certain types of foods. The sirtfoods permitted and consumed throughout the programme are generally low in calories. With green juices and limited food choices, this diet only fairs slightly better than a detox cleanse but is far off from being a healthy weight loss programme.

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The sirtfood creators also failed to promote a sustainable weight management plan, leaving one to wonder how to manage their newly found success in the long run. Sadly, repeating the two phases to promote further weight loss, as suggested, only sets one up for failure, which could lead to more restrictive eating and possibly emotional distress. These together may cause binge eating and the dieter could regain all the weight they had lost.

The truth is, there are no short cuts to weight loss. Healthy weight loss should be gradual, at just 0.5kg to 1kg a week, through engaging in physical activity and eating a variety of wholesome and minimally processed foods, including vegetables, fruits, whole grains, lean proteins and healthy fats.

Our advice? Be wary of weight loss claims that seem too promising.

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