Largest review of all available evidence to date finds clear link between eating red or processed meat and a higher risk of coronary heart disease.
Besides being major contributors of greenhouse gas emissions, deforestation and biodiversity loss, there is an established link between even moderate intakes of red/processed meat and an increased risk of bowel cancer.
Our new study, published in Critical Reviews in Food Science and Nutrition, demonstrates that regular consumption of red/processed meat also increases the risk of coronary heart disease, caused by narrowed arteries that supply the heart with blood.
Globally, coronary heart diseases are the leading cause of death, claiming around nine million lives each year. Even when they are not fatal, they can be highly debilitating and severely reduce quality of life. So preventing coronary heart diseases is just as important as treating them.
We reviewed the evidence from thirteen large-scale prospective cohort studies: investigations that track a group of people over time. In total, these involved over 1.4 million people. All the participants in these studies completed detailed dietary assessments, and their health was tracked for up to 30 years.
Our main findings were:
- Each 50 g/day higher intake of processed meat (e.g. bacon, ham, and sausages) increased the risk of coronary heart disease by 18%.
- Each 50 g/day higher intake of unprocessed red meat (such as beef, lamb and pork) increased the risk of coronary heart disease by 9%.
- There was no clear link between eating poultry (such as chicken and turkey) and an increased risk of coronary heart disease.
Combining these with results of other studies suggests that the best diet for good heart health is a plant-based diet, with lots of fruit and vegetables, and limited alcohol. But just reducing your intake of red and processed meat could make a difference.
Based on current coronary heart disease statistics and dietary intakes in the UK, our study suggests that if 100 people reduced their unprocessed red meat intake by three-quarters: for example from four times a week to once a week, or if they stopped consuming processed meat altogether, deaths from coronary heart disease would decrease from 10 in 100 down to 9 in 100. This may not sound like a lot at an individual level but it relieves pressure on health services, and having this information allows people to make their own choices.
There are lots of other things people can do to reduce their risk of coronary heart disease. These include being physically active, maintaining a healthy weight, not smoking and avoiding high blood pressure.
Our latest results give a further incentive for people to limit their consumption of red and processed meat, though more research is needed to understand how red and processed meat increase the risk of coronary heart disease.