Eating animal protein foods is not linked to an increased risk of death and may even offer protective benefits against cancer-related mortality, according to new research from McMaster University in Canada.
The study, published in Applied Physiology, Nutrition, and Metabolism, analyzed data from nearly 16,000 adults aged 19 and older using the National Health and Nutrition Examination Survey (NHAMES III). Researchers examined the amount of animal and plant protein people typically consume and whether those patterns were associated with their risk of dying from heart disease, cancer, or any other cause.
Thus, they found no increased risk of death associated with higher animal protein intake. In fact, the data showed a modest but significant reduction in cancer-related mortality among people who consumed more animal protein.
"There's a lot of confusion surrounding protein: how much to eat, what type, and what it means for long-term health. This study provides clarity, which is important for anyone trying to make informed, evidence-based decisions about what they eat," explains Stuart Phillips, professor and chair of the Department of Kinesiology at McMaster University, who oversaw the research.
To ensure the reliability of the results, the team used advanced statistical methods, such as the National Cancer Institute (NCI) method and the multivariate Markov Chain Monte Carlo (MCMC) model, to estimate long-term dietary intake and minimize measurement error.
"It was essential that our analysis use the most rigorous and recognized methods for assessing habitual intake and mortality risk. These methods allowed us to account for fluctuations in daily protein intake and provide a more accurate picture of long-term dietary habits," says Phillips.
The researchers found no association between total protein, animal protein, or plant protein and the risk of death from any cause, cardiovascular disease, or cancer. When both plant and animal proteins were included in the analysis, the results remained consistent, suggesting that plant protein has a minimal impact on cancer mortality, while animal protein may offer a small protective effect.
According to experts, observational studies like this one can't prove cause and effect; however, they are valuable for identifying patterns and associations in large populations. Combined with decades of evidence from clinical trials, the findings support the inclusion of animal proteins as part of a healthy dietary pattern.
"When you consider both observational data like this and clinical research, it's clear that both animal and plant protein foods promote health and longevity," concluded lead researcher Yanni Papanikolaou, president of Nutritional Strategies.