Apparently the daily calorie intake in midlife can affect your cognitive abilities and the risk for Alzheimer’s disease later on. On average the brain shrinks with age, but being overweight appears to accelerate the process.
Being overweight might shrink your brain
A prospective study that examined the relationship between obesity and brain shrinkage, followed a group of women for 24 years. Atrophy of the occipital, parietal, frontal, and temporal lobes were measured when the women were 70 – 84 years old.
Blue:Frontal lobe, yellow:Parietal lobe, green:Temporal lobe, red:Occipital lobe
The result showed that women with cerebral atrophy in the temporal lobes had higher body max index (BMI) at each of the four examinations years. Each 1 kg/m2 increase in BMI increased the odds of degeneration in the temporal lobes by 12-16%. In this research the brain shrinkage was restricted to the temporal lobes, but other research has shown cerebral atrophy in the frontal lobes, anterior cingulate gyrus, hippocampus and thalamus.
In addition to having an impact on brain structure, being overweight in midlife is associated with lower cognitive abilities and accelerated decline of those abilities later in life.
It is altogether possible that the fat-distribution on the body is relevant. One research showed stronger association between obesity and poor performance on tests that measured cognitive abilities, when the extra pounds park themselves around the midsection of the body.
Gender might also be of importance, as the association between cognitive abilities and BMI are, in some resarch, only seen in men but not women.
Excess calories and Alzheimer’s disease
Being overweight in midlife can increase the risk of Alzheimer’s disease later in life. Some studies show this to be true only for women, but others for both women and men. One research with over 10 thousand participants aged 40-45 showed, for example, that those who were overweight at that time, had three times more risk than people in normal weight for developing Alzheimer’s disease and five times more risk for developing vascular dementia, 30 years later. Another study showed that the risk for cognitive impairment and/or dementia was only increased if the accumulation of fat was around the waist.
Here is að video from YouTube, where dr. Larry McCleary discusses how obesity and brain health are related:
Dahl, A., Hassing, L. B., Fransson, E., Berg, S., Gatz, M., Reynolds, C. A. o.fl. (2010). Being overweight in midlife is associated with lower cognitive ability and steeper cognitive decline in late life. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 65A(1), 57-62.
Gustafson, D., Lissner, L., Bengtsson, C., Bjorkelund, C. og Skoog, I. (2004). A 24-year follow-up of body mass index and cerebral atrophy. Neurology, 63(10), 1876 – 1881.
Jeong, S. K., Nam, H. S., Son, M. H., Son, E. J. og Cho, K. H. (2005). Interactive effect of obesity indexes on cognition. Dementia and Geriatric Cognitive Disorders, 19(2-3), 91-96.
West, N. A. og Haan, M. N. (2009). Body adiposity in late Life and risk of dementia or cognitive impairment in a longitudinal community-based study. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences.
Whitmer, R. A., Gunderson, E. P., Quesenberry, C. P., Zhou, J. og Yaffe, K. (2007). Body mass index in midlife and risk of Alzheimer disease and vascular dementia. Current Alzheimer Research, 4, 103-109.