What Is the Sirtfood Diet and Is It Safe?

a collage of foods you can eat on the Sirtfood diet
a collage of foods you can eat on the Sirtfood diet

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The Sirtfood diet is one of the latest trending diets in the nutrition world. It's no wonder, considering it permits chocolate, coffee and red wine. And it doesn't hurt that several European celebrities have championed the diet for the health and weight-loss benefits they claim it provides.

But what exactly are Sirtfoods? And is it safe to follow a restrictive diet that includes alcohol and chocolate? In this article, we answer these questions to help you determine whether you should try this growing diet trend. Here's what you need to know.

What Is the Sirtfood Diet?

As explained in the book The Sirtfood Diet by authors Aidan Goggins and Glen Mattern, the Sirtfood diet is a three-week weight-loss program based on consuming foods high in sirtuins (SIRTs) for better metabolic health. "The goal of the Sirtfood diet is to help people lose weight by eating foods with powerful 'super-nutrients' that may help activate the body's natural fat-burning pathways," says Erin Palinski-Wade, RD, CDCES, registered dietitian and author of 2-Day Diabetes Diet.

Inspired by a 2013 study published in Oxidative Medicine and Cellular Longevity, Goggins and Mattern set out to create a weight-loss program rich in sirtuin-activating foods shown to be health promoting. SIRTs are a class of several proteins and anti-aging genes associated with several health benefits, such as reduced inflammation, slower aging, increased longevity and improved metabolism.

The Sirtfood diet has several phases. Phase one lasts one week and is designed to help you lose 7 pounds by "kickstarting your metabolism" through extreme calorie restriction. For the first three days, Sirtfood dieters can only consume 1,000 calories spread across three green juices and one meal from the Sirtfood Diet book.

The next four days see caloric intake increase to 1,500 in the form of two green juices and two Sirtfood meals. The next phase entails a two-week maintenance period with the intention of further weight loss. Sirtfood-dieters are allowed to have three Sirtfood meals and one green juice daily during this phase.

Kelsey Kunik, RDN, a registered dietitian nutritionist and nutrition advisor for Zenmaster Wellness, tells EatingWell, "The Sirtfood diet is based on the idea that SIRTs can turn on a 'skinny gene,' making weight loss easy. Specific foods are thought to activate these proteins, helping people easily lose weight."

Related: 1,800-Calorie Diet Plan for Weight Loss

Sirtfood Diet Foods List

Based on findings from the 2013 study, the Sirtfood diet comprises mainly plant-based whole foods. These include fruits, vegetables, select whole grains, leafy greens, herbs, spices, specific oils and beverages that they claim can activate sirtuins for health and longevity benefits. While meat is optional, it's not required and the diet can be modified for those following vegan and vegetarian eating patterns as well. Foods allowed on the Sirtfood diet include:

  • Apples

  • Arugula

  • Beans

  • Buckwheat

  • Capers

  • Celery

  • Chiles

  • Cocoa

  • Coffee

  • Cruciferous vegetables

  • Extra-virgin olive oil

  • Garlic

  • Green tea

  • Kale

  • Medjool dates

  • Oily fish (optional)

  • Parsley

  • Red onion

  • Red wine

  • Seaweed

  • Shallots

  • Soy products (e.g., tofu, tempeh, edamame)

  • Strawberries

  • Turmeric

  • Walnuts

Is the Sirtfood Diet Safe?

Pros of the Sirtfood Diet

Sirtuins may provide anti-aging benefits: High-SIRT foods may offer several longevity benefits, according to a study published in Nutrients in October 2022. The research suggests Sirtfoods may lower inflammation, promote homeostasis and support cellular function—all critical components of healthy aging.

Sirtuins may promote weight loss: The research behind sirtuins' weight-loss benefits comes primarily from animal studies, which means they may not be broadly applicable to humans. Weight loss has been associated with increased SIRT levels in the liver and fat tissues of people with obesity, says a 2016 study. However, the weight loss resulting from the Sirtfood diet may also be attributed to calorie restriction.

Sirtuins are high in antioxidants: Since the Sirtfood diet is abundant in plant-based foods rich in antioxidants, eating Sirtfoods may provide several health benefits. Antioxidants have been shown to protect against free radical damage and reduce chronic disease risk, according to the National Institutes of Health.

Related: Best Antioxidant-Rich Foods

Cons of the Sirtfood Diet

Extreme calorie restriction can lead to health issues: While creating a calorie deficit is necessary for weight loss, trying to sustain too large a deficit for an extended period may result in several health problems. For example, restricting your daily diet to 1,200 calories or less is too low for most people to meet their needs and can cause adverse side effects, according to the NIH. Potential symptoms include dizziness, nausea, extreme hunger, fatigue, headaches and gallstones.

The Sirtfood diet may cause nutritional gaps: Restricting calories and not eating a diverse range of foods can result in nutritional deficiencies and weaken the immune system. "While most of the foods on the Sirtfood diet are incredibly nutritious, going three weeks without including a variety of foods can leave huge nutrient gaps," cautions Kunik.

It's not sustainable: The key to success with any weight-loss plan is adopting a way of eating that you find enjoyable and can sustain long-term. Consuming only juices and one or two meals daily while in a calorie deficit is unsustainable and unhealthy for most people.

Should You Try the Sirtfood Diet?

While the Sirtfood diet is generally safe for most people, EatingWell discourages restrictive eating patterns that can potentially lead to negative health outcomes and nutritional deficiencies. Don't try this diet or similar ones if you have diabetes or a history of disordered eating. According to nutrition experts, low calorie intake and skipping meals can affect insulin production, causing blood sugar drops and medication imbalances for people with diabetes.

"While including Sirtfoods in your diet is a great way to include more powerful plant antioxidants that could increase the activation of the SIRT gene, restricting other foods and relying on juices for several weeks at a time is likely to result in rebound eating when the diet is over," says Kunik. As with any diet or weight-loss plan, consult your physician and registered dietitian first to help determine what's right for you.

Frequently Asked Questions

1. What is a typical Sirtfood meal?

A typical Sirtfood meal includes foods from the three Sirtfood groups: proteins, polyphenols and healthy fats. "For breakfast, one could have a smoothie made with matcha green tea, oats, almond milk and blueberries; for lunch, they could have salmon with roasted asparagus and extra-virgin olive oil; and for dinner, they could have a kale salad with apples, walnuts and balsamic vinegar," says Palinski-Wade.

2. Are eggs a Sirtfood?

Though not technically considered a Sirtfood, eggs are allowed on the Sirtfood diet because of their high protein content. "Eggs contain all essential amino acids, making them an important source of nutrition for those following the Sirtfood diet," says Palinski-Wade.

3. Is the Sirtfood diet the same as Keto?

The Sirtfood diet is different from the Keto diet. The Keto diet focuses on significant carbohydrate restriction and increasing fat intake to get the body into ketosis (burning fat for energy instead of glucose from carbs). Instead, the Sirtfood diet encourages fat loss through extreme calorie restriction and consumption of nutrient-dense foods.

"While many Sirtfoods are low in carbohydrates, counting carbs or intentionally limiting them is unnecessary. Dates, buckwheat and strawberries are Sirtfoods that are higher in carbohydrates and can be eaten freely, while not allowed or limited on a keto diet," explains Kunik.

The Bottom Line

The Sirtfood diet contains many healthy, nutrient-dense foods that can aid in weight loss and help prevent chronic disease. However, its restrictive nature and extreme calorie deficits are unsustainable long-term and can lead to nutritional gaps. Also, the Sirtfood diet isn't recommended for people with certain health conditions, like diabetes or disordered eating. Instead, choose to make more realistic healthy dietary changes that you'll actually enjoy so you can sustain them for the long term.

Keep Reading: What Is a Green Mediterranean Diet—and Is It Healthy?