Eating processed meat could increase dementia risk
University of Leeds
Scientists from the University's Nutritional Epidemiology Group used data from 500,000 people, discovering that consuming a 25g serving of processed meat a day, the equivalent to one rasher of bacon, is associated with a 44% increased risk of developing the disease.
But
their findings also show eating some unprocessed red meat, such as beef, pork
or veal, could be protective, as people who consumed 50g a day were 19% less
likely to develop dementia.
The
researchers were exploring whether there is a link between consumption of meat
and development of dementia, a health condition which affects 5%-8% of over 60s
worldwide.
Their
results, titled Meat consumption and risk of incident dementia: cohort study of
493,888 UK Biobank participants, are published today in the American
Journal of Clinical Nutrition.
Lead researcher Huifeng Zhang, a PhD student from Leeds' School of Food Science and Nutrition, said: "Worldwide, the prevalence of dementia is increasing and diet as a modifiable factor could play a role.
"Our
research adds to the growing body of evidence linking processed meat
consumption to increased risk of a range of non-transmissible diseases."
The
research was supervised by Professors Janet Cade and Laura Hardie, both at
Leeds.
The
team studied data provided by UK Biobank, a database containing in-depth
genetic and health information from half a million UK participants aged 40 to
69, to investigate associations between consuming different types of meat and
risk of developing dementia.
The
data included how often participants consumed different kinds of meat, with six
options from never to once or more daily, collected in 2006-2010 by the UK
Biobank. The study did not specifically assess the impact of a vegetarian or
vegan diet on dementia risk, but it included data from people who said they did
not eat red meat.
Among
the participants, 2,896 cases of dementia emerged over an average of eight
years of follow up. These people were generally older, more economically
deprived, less educated, more likely to smoke, less physically active, more
likely to have stroke history and family dementia history, and more likely to
be carriers of a gene which is highly associated with dementia. More men than
women were diagnosed with dementia in the study population.
Some
people were three to six times more likely to develop dementia due to well
established genetic factors, but the findings suggest the risks from eating
processed meat were the same whether or not a person was genetically
predisposed to developing the disease.
Those
who consumed higher amounts of processed meat were more likely to be male, less
educated, smokers, overweight or obese, had lower intakes of vegetables and
fruits, and had higher intakes of energy, protein, and fat (including saturated
fat).
Meat
consumption has previously been associated with dementia risk, but this is
believed to be the first large-scale study of participants over time to examine
a link between specific meat types and amounts, and the risk of developing the
disease.
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
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."