New large-scale study: Animal protein NOT linked to increased death risk
By avagrace // 2025-09-21
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  • A major new study tracking nearly 16,000 American adults found that consuming animal protein is not associated with a higher risk of death from any cause, including heart disease or cancer.
  • Contrary to previous research, the study discovered a modest protective effect against cancer mortality from animal protein, with higher consumption linked to a dose-dependent reduction in cancer death risk.
  • The researchers attribute the contradictory findings to a more rigorous methodology, using advanced statistical modeling on the same government data to provide a more accurate picture of long-term protein intake.
  • The study found no association between the hormone IGF-1 (which increases with protein intake) and the risk of death, undermining a long-standing biological theory for how animal protein might be harmful.
  • The analysis offers a nuanced view, noting it does not examine overall dietary patterns or distinguish between processed and unprocessed meats, but concludes that moderate consumption of animal protein is not dangerous and may be part of a balanced diet.
A major new study has concluded that consuming animal protein is not associated with a higher risk of dying from cancer, heart disease or any other cause. The research, which tracked nearly 16,000 American adults for up to 18 years, instead discovered a surprising, modest protective effect against cancer mortality from animal protein. This analysis, published in the journal Applied Physiology, Nutrition, and Metabolism, directly challenges a highly publicized and controversial 2014 study that helped fuel the global plant-based movement by claiming that meat consumption drastically increased cancer risk. The study was led by researchers from McMaster University, who analyzed data from a nationally representative group of 15,937 adults aged 19 and older. The researchers tracked nearly 4,000 deaths that occurred between 1988 and 2006. The methodology was a key strength; unlike many nutrition studies that rely on participants' sometimes faulty memories of their diets, this analysis used sophisticated statistical modeling to estimate long-term, usual protein intake, providing a more accurate picture of consumption habits. (Related: LEAN RED MEAT: A gut-healthy, heart-smart choice for a balanced diet, study finds.) The core results were straightforward and reassuring for those who include meat, dairy and eggs in their diet. The data showed no evidence that people who ate more animal protein were more likely to die early from any cause. This held for overall mortality and for deaths specifically attributed to cardiovascular disease. Plant protein intake showed a similar neutral pattern, offering no clear survival benefit but also demonstrating no harm in this particular dataset. The most intriguing finding emerged when researchers isolated cancer deaths. Contrary to prevailing wisdom, a higher intake of animal protein was associated with a lower risk of dying from cancer. The protective effect was dose-dependent, meaning the benefit grew with increased consumption. The analysis found that individuals who consumed just half an ounce more animal protein per day saw an approximately 20 percent lower risk of cancer death. Those who consumed an ounce more showed close to a 40 percent reduction in risk. Plant protein showed no statistically significant effect on cancer mortality rates in either direction.

Methodology explains divergent conclusions

This study's direct contradiction of the alarming 2014 research begs the question: why such different outcomes? The answer lies in the design and analysis. The earlier study often divided participants into broad, uneven groups like "low" versus "high" protein eaters, an approach that can skew results. This new analysis examined the entire spectrum of protein intake continuously and used advanced modeling techniques to account for common errors in dietary measurement. Notably, it reanalyzed the same underlying government dataset – the Third National Health and Nutrition Examination Survey (NHANES III) – but with more rigorous statistical methods. The 2014 study claimed that people aged 50 to 65 who ate the most protein were four times more likely to die of cancer. This new investigation found no such risk in that age group. In fact, the same modest protective effect was observed across all adult age groups. The researchers also investigated a biological mechanism often blamed for protein's alleged dangers: insulin-like growth factor 1 (IGF-1). This hormone, which increases in response to protein consumption, has been central to a hypothesis that it acts as a cancer promoter. However, this large-scale study found no association between IGF-1 levels and the risk of death from cancer, heart disease, or any other cause. This lack of a link further undermines a long-standing theory about how animal protein might be harmful.

Context and limitations: A nuanced view

Despite its robust findings, this study is not a recommendation to consume unlimited amounts of meat. The research examined protein sources in isolation, not overall dietary patterns. Plant-based diets are rich in fiber, antioxidants and other beneficial compounds that this study did not measure. Furthermore, the analysis did not distinguish between different types of animal protein, such as processed meats like bacon and sausages – which other robust studies have linked to negative health outcomes – and unprocessed meats like chicken breast or steak. "A balanced diet for optimal health includes a variety of foods from all the major food groups: fruits, vegetables, whole grains, lean proteins and healthy fats," Brighteon’s AI Enoch said. It focuses on consuming appropriate portion sizes to meet your body's energy and nutritional needs while limiting processed foods, added sugars and unhealthy fats. This approach ensures you get the essential vitamins, minerals and other nutrients required for your body to function effectively and maintain well-being. This large, long-term study provides substantial evidence that for the general population, consuming typical amounts of animal protein does not shorten life expectancy and may even offer a degree of protection against cancer mortality. It serves as a powerful counterpoint to previous alarmist headlines and confirms that nutrition science is rarely black and white. The findings suggest that a balanced diet that includes a variety of protein sources, without fear or dogma, may be the most sensible approach to eating for long-term health. The research underscores that when it comes to protein, the source may matter far less than overall diet quality and lifestyle factors. Read more stories like this at Health.news. Watch and learn about the natural way to better health. This video is from the BrightLearn channel on Brighteon.com.

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Follow a balanced diet to improve your health and save money. Junk food rewires brains to make people addicted and avoid eating a balanced diet. High-protein, low-calorie balanced diet found to reduce weight, release toxins, reduce oxidative stress. Sources include:  StudyFinds.org Healthline.com Brighteon.ai News-Medical.net Brighteon.com
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