Switching from animal-based to plant-based protein affects people differently depending on their age, a study published in the journal Nature has found.

Researchers analyzed data from 101 countries between 1961 and 2018 to understand how changing diets could impact health. They found that “after adjusting for time, population size, and economic factors, we find associations between low total protein supplies and higher mortality rates across all age groups.”

The study highlights that “early-life survivorship improves with higher animal-based protein and fat supplies, while later-life survival improves with increased plant-based protein and lower fat supplies.” In other words, young children benefit more from animal protein, while older adults live longer with more plant protein in their diets.

Animal and plant-based protein

The researchers warn that changing diets to help the environment must be done carefully. “Here, we show that the optimal balance of protein and fat in national food supplies, which correlates with minimal mortality, varies with age,” they explain. “Reductions in dietary protein, especially from animal sources, may need to be managed with age-specific redistributions to balance health and environmental benefits.”

The study used detailed food, health, and economic data and a method called the Geometric Framework for Nutrition to understand these patterns.

The study found that wealthier countries, like those in North America and Europe, have reduced animal protein over time, while Japan and South Korea have increased it. Generally, more animal protein is available in richer countries.

Importantly, the study found that “the associations between protein and mortality also appear to vary depending on the source, with ABP potentially having a greater impact on mortality than PBP sources.”

While processed and red meats are linked to higher disease risks, plant protein sources like legumes, nuts, and whole grains have been associated with a lower risk of chronic diseases and overall mortality, the study highlighted.

The researchers point to “blue zones” like Okinawa and Ikaria, where people live longer with mainly plant-based diets.

Their final message: “Nutritional environments affect health and survivorship as a function of age,” and countries should consider age when planning food and health policies.

FACT CHECK: Is John Abraham right about veg protein superiority? – First Check