Processed Meats Increase Risk of Dementia

A recent study published in Neurology on 11 February 2025, led by researchers from Brigham and Women’s Hospital, has investigated the relationship between long-term red meat consumption and the risk of dementia and cognitive decline in U.S. adults. The study utilised data from the Nurses’ Health Study and the Health Professionals Follow-Up Study, encompassing approximately 170,000 participants over a 43-year period. 

Key Findings:

  • Processed Red Meat and Dementia Risk: Individuals with the highest intake of processed red meats—such as bacon, sausages, and hot dogs—exhibited a 13% higher risk of developing dementia compared to those with lower consumption levels.
  • Cognitive Decline: High consumption of processed red meats was associated with a 14% increase in subjective cognitive decline, indicating a perceived worsening of cognitive abilities over time.
  • Unprocessed Red Meat: The study found that unprocessed red meats, such as beef, lamb, and pork, also contributed to cognitive risks, potentially due to harmful substances like nitrates, sodium, and saturated fats present in these meats.

Mechanisms Behind the Findings:

The detrimental effects of processed red meats on cognitive health are believed to be linked to several factors:

  • Nitrates and Nitrites: Commonly used as preservatives in processed meats, these compounds can form nitrosamines, which have been implicated in neurodegenerative processes.
  • High Sodium Content: Elevated sodium levels can lead to hypertension, a known risk factor for vascular dementia.
  • Saturated Fats: High levels of saturated fats in processed meats are associated with cardiovascular diseases, which can indirectly affect brain health.

Dietary Recommendations:

Based on the findings, the researchers suggest several dietary modifications to mitigate dementia risk:

  • Reduce Processed Red Meat Intake: Limiting the consumption of processed meats can lower the risk of cognitive decline.
  • Substitute with Healthier Protein Sources: Replacing processed red meats with alternatives such as fish, poultry, nuts, and legumes has been associated with a reduced risk of dementia. For instance, substituting processed red meat with fish was linked to a 28% reduction in dementia risk.
  • Adopt Brain-Healthy Diets: Diets like the Mediterranean, DASH, and MIND diets, which are low in red meat and rich in fruits, vegetables, whole grains, and healthy fats, have been associated with decreased dementia risks.

Conclusion:

This extensive study underscores the importance of dietary choices in maintaining cognitive health. Limiting the intake of processed red meats and opting for healthier protein sources may significantly reduce the risk of dementia and support long-term cognitive function.