Dementia is a broad term that includes Alzheimer’s disease, vascular dementia, and other forms of the condition. It is characterized by the loss of memory, language, problem-solving skills, and/or other aspects of cognitive function. Approximately 50 million people worldwide have dementia. A recent study investigated links between meat consumption and dementia risk.

Meat is rich in several essential nutrients, including protein, iron, zinc, and vitamin B12. Findings from epidemiological studies suggest that diets high in red and processed meats increase a person’s risk for type 2 diabetes, cardiovascular disease, cancer (particularly colorectal cancer), and all causes of premature death.

The present study involved more than 493,000 adults enrolled in the UK Biobank, a biomedical database containing health information about people living in the United Kingdom. The participants completed a food frequency questionnaire in which they provided answers about their meat consumption, to include processed meat, unprocessed poultry, and unprocessed red meat (beef, lamb, and pork). The authors of the study defined “processed meat” as bacon, ham, sausages, meat pies, kebabs, burgers, and chicken nuggets.

They found that eating unprocessed red meat was linked with a lower risk of dementia and Alzheimer’s disease, whereas eating processed meat was linked with higher risk. They did not identify any associations between poultry consumption and dementia risk. Each additional 50-gram per day increment in unprocessed red meat intake decreased their risk for all causes of dementia by 19 percent and decreased their risk for Alzheimer’s disease by 30 percent. In contrast, each additional 25-gram per day increment in processed meat intake increased a person’s risk for all types of dementia by 44 percent and increased their risk for Alzheimer’s disease by 52 percent.

High levels of protein and iron in unprocessed red meat may partially explain the link between unprocessed meat intake and lower risk of dementia. Adequate protein intake has been linked with lower dementia risk in older adults, and iron is necessary for many aspect of brain health, including the production of neurotransmitters and myelin. On the other hand, processed meat contains nitrites and N-nitroso compounds, which may promote oxidative stress, lipid peroxidation, and activation of proinflammatory cytokines or other mechanisms potentially involved in the development of dementia.

These findings suggest that eating processed meat increases a person’s risk for developing dementia but eating unprocessed meat does not. They also underscore the importance of distinguishing between processed and unprocessed meat in nutrition studies. This was a large, well-designed prospective study that accounted for multiple confounding factors, including age, gender, ethnicity, socioeconomic status, educational level, BMI, physical activity level, smoking status, typical sleep duration, stroke history, family history of dementia, and dietary factors (including consumption of vegetables, fruits, fish, tea, coffee, and alcohol).

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