Processed meat consumption increases dementia risk, finds study
UK: Consumption of a 25g serving of processed meat per day increases the risk of dementia development by 44%, finds a recent study in the American Journal of Clinical Nutrition.
Findings indicate that intake of some unprocessed red meat such as pork or veal, beef, could be protective -- people who consumed 50g a day were 19% less likely to develop dementia.
The prevalence of dementia is increasing worldwide and diet could play a role. In cross sectional studies, meat consumption has been shown to be associated with dementia risk, but there is no proper understanding of the specific amounts and types related to risk of incident dementia. Huifeng Zhang, University of Leeds, Leeds, UK, and colleagues aimed to investigate associations between meat consumption and risk of incident dementia in the UK Biobank cohort.
For the purpose, the researchers estimated meat consumption using a short dietary questionnaire at recruitment and repeated 24-h dietary assessments. Using electronic linkages to hospital and mortality records, they identified incident all-cause dementia comprising Alzheimer disease (AD) and vascular dementia (VD).
HRs for each meat type in relation to each dementia outcome were estimated in Cox proportional hazard models. Interactions between meat consumption and the apolipoprotein E (APOE) ε4 allele were additionally explored.
There are around 50 million dementia cases globally, with around 10 million new cases diagnosed every year. Alzheimer's Disease makes up 50% to 70% of cases, and vascular dementia around 25%. Its development and progression are associated with both genetic and environmental factors, including diet and lifestyle.
Ms Zhang said: "Further confirmation is needed, but the direction of effect is linked to current healthy eating guidelines suggesting lower intakes of unprocessed red meat could be beneficial for health."
Professor Janet Cade said: 'Anything we can do to explore potential risk factors for dementia may help us to reduce rates of this debilitating condition. This analysis is a first step towards understanding whether what we eat could influence that risk."
Key findings of the study include:
- Among 493,888 participants included, 2896 incident cases of all-cause dementia, 1006 cases of AD, and 490 cases of VD were identified, with mean ± SD follow-up of 8 ± 1.1 y.
- Each additional 25 g/day intake of processed meat was associated with increased risks of incident all-cause dementia (HR: 1.44) and AD (HR: 1.52).
- In contrast, a 50-g/d increment in unprocessed red meat intake was associated with reduced risks of all-cause dementia (HR: 0.81) and AD (HR: 0.70).
- The linear trend was not significant for unprocessed poultry and total meat. Regarding incident VD, there were no statistically significant linear trends identified, although for processed meat, higher consumption categories were associated with increased risks.
- The APOE ε4 allele increased dementia risk by 3 to 6 times but did not modify the associations with diet significantly.
"These findings highlight processed-meat consumption as a potential risk factor for incident dementia, independent of the APOE ε4 allele," concluded the authors.
The study titled, "Meat consumption and risk of incident dementia: cohort study of 493,888 UK Biobank participants," is published in the American Journal of Clinical Nutrition.