Increased meat consumption associated with early death

‘We are not saying everybody should become vegetarian or vegan,’ lead author of the study, Dr Frank B Hu, Professor of Nutrition and Epidemiology at the Harvard TH Chan School of Public Health, said.
 
‘However, there is a significant benefit if you replace some of the red meat with plant-based foods.’
 
The large-scale, longitudinal study, the results of which were recently published in the British Medical Journal, followed 55,553 women and 27,916 men without cardiovascular disease or cancer at baseline over a period of eight years from the 1980s and 1990s, recording their death rates over the final eight years. The study concluded in 2010.
 
Participants, who were all health professionals in the US, completed a questionnaire at the beginning of the study that measured the frequency of consumption of different types of foods, including red meats and processed meats. They then completed the same questionnaire every four years. Researchers also collected detailed data on additional lifestyle factors, such as diet and physical activity.
 
The study found that changes in consumption of red meat predicted mortality, with an association between increased consumption and risk of death. For example, those who increased their total weekly consumption of red meat by 3.5 servings or more over the first eight-year period also displayed a 10% higher risk of death over the following eight years.
 
The effects of different red meats were also analysed further, with those who increased their intake of processed red meat – items such as bacon, sausages and salami – by 3.5 servings a week, experiencing a 13% higher risk of death, while those who increased intake of unprocessed red meat showed a 9% higher risk.
 
Conversely, there was an associative effect of reducing consumption of red and processed meats. For example, one fewer serving of red meat a day – replaced by foods such as chicken, fish, legumes and vegetables – resulted in a 17% lowered risk of death over the next eight years.
 
Given the study is an observational one, its authors have been careful to acknowledge it can establish only association, not cause. They also recognise other limitations, including participants being restricted to health professionals, and a lack of exploration of why participants’ consumption habits may have changed, which may have had some influence over the results.
 
However, the study also repeatedly assessed diet and lifestyle factors, adjusted for age, and followed participants over a long period of time. As such, researchers believe it is safe to conclude that life span can be increased by changing the source of protein in a diet or increasing consumption of plant-based foods.

Diet nutrition plant-based red meat consumption risk factors