Is this the new 5:2 diet? Eating more plant-based meals could boost longevity

A new book by Professor Luigi Fontana with recipes from Healthy Longevity Chef Marzio Lanzini at the University of Sydney’s Charles Perkins Center (CPC) has set out a medical science-backed plan for eating more plant-based meals to enhance overall health and longevity.

Plant Power is the first book to be published under the pair’s collaboration at the CPC-RPA Healthy for Life program. It draws on Fontana’s research into longevity and Lanzini’s work in the culinary world to support the increasing number of people turning to plant-based eating, vegetarianism and veganism, with as many as 42% of Australians choosing to eat less meat or none at all.

“More people are moving away from meat-centric diets and incorporating more plant-based food, a trend that is not just about ethical choices but also about promoting better health and longevity,” said Fontana.

“Healthy longevity is about fueling your body with the right nutrients to activate cellular repair and gut health,” he said. “What we propose is simple. We recommend people start to experiment by shifting to two plant-based days a week, trying new recipes, discovering new flavors, and eventually increasing this to five days a week.”

The science behind why some plant-based diets boost longevity

Plant Power builds on a review article co-authored by Fontana and Professor Walter Willett, former Chair of the Department of Nutrition at Harvard published in the European Heart Journal. The research provides a comprehensive analysis of the health effects of both healthy and unhealthy plant-based diets. It found that plant-based diets incorporating wholefoods are far better than ones which include ultra-processed and refined foods.

Fontana’s research has also found longevity is driven by two key factors: nutrient-sensing pathways and the gut microbiome: “The right foods, predicated on a predominantly plant-based diet, activate mechanisms that slow aging, reduce inflammation, and enhance metabolism,” he said. “Secondly, without enough fiber-rich plant foods, beneficial gut bacteria die off, weakening immunity and increasing disease risk.”

Debunking the myth that all plant-based diets are healthy

According to Fontana, in clinical practice it is common to meet patients who assume that simply removing meat from their diet will naturally lead to better health.

“The reality is that achieving a well-rounded, nutritious diet involves much more than the exclusion of animal products. People may cut out meat but continue to eat a diet full of ultra-processed foods which increases the risk of diseases like stroke and dementia, and premature death,” he said.

Lanzini, who runs the Charles Perkins Center’s metabolic kitchen and instructs on science-backed eating, co-developed the book’s plant-based recipes. He said, “What we recommend requires a thoughtful approach to meal planning, ensuring that all essential nutrients are properly included.”

“People often opt for refined carbohydrates, fats and salt, such as white bread, frozen pizza, instant noodles, pre-packaged meals, pastries, cakes, cookies, French fries, chips, plant-based meat substitutes and sugary beverages.

“Instead, we recommend bringing it back to whole foods.”

A healthy, primarily plant-centric fiber-rich diet includes:

• Minimally processed whole grains (e.g., brown rice, wheat, spelt, barley, millet, rye, corn, buckwheat)
• legumes (e.g., chickpeas, lentils, soy, black, kidney, pinto, navy, cannellini, adzuki, fava beans, and tofu)
• nuts (e.g., walnuts, almonds, cashews, pistachios, hazelnuts, pecans, macadamia nuts, Brazil and pine nuts);
• seeds (e.g., flaxseeds, sesame, sunflower, pumpkin and chia seeds);
• low-glycemic fruits (e.g., strawberries, raspberries, blackberries, blueberries, cherries, kiwifruit, plums, peaches, apples, grapefruit, oranges);
• unsaturated fats (such as extra-virgin olive oil, avocados).