Elderly men and women who consumed higher levels of calcium and vitamin D are significantly more likely to have greater volumes of brain lesions, regions of damage that can increase risk of cognitive impairment, dementia, depression and stroke.
Duke University scientist Dr. Martha Payne reported this finding at Experimental Biology 2007, in Washington, DC. Her presentation, on May 1, is part of the scientific program of the American Society for Nutrition.
Dr. Payne and her co-investigators from Duke and the University of North Carolina examined magnetic resonance imaging (MRI) scans from 232 men and women (79 men, 153 women) between the ages of 60 and 86 (average age 71). All the subjects had at least some brain lesions of varying sizes, including the extremely miniscule ones often seen in even healthy older persons, but those who reported consuming more calcium and vitamin D were markedly more likely to have higher total volume of brain lesions as measured across numerous MRI scans.
Age, hypertension, and other medical conditions - all factors related to the presence of brain lesions - were taken into account during statistical analysis (were controlled for) and were found not to account for the strong relationship between total lesion volume and high intake of calcium and vitamin D. Since the calcium/vitamin D research was part of a longitudinal study of late-life depression, almost half the subjects had been diagnosed with depression. However, the presence or absence of depression also did not appear to influence of relationship between calcium, vitamin D, and brain lesions.
In earlier studies, Dr. Payne's team had found that individuals who consumed more high-fat dairy products had more brain lesions than those who did not follow such a diet but that fat intake in general was not a significant factor. If not the fat, the researchers asked, what was it about a high fat dairy diet that accounts for the positive correlation with brain lesions? This new study points the finger to a prominent component of dairy - namely calcium - and the Vitamin D that is found in many dairy products and vitamin D-fortified foods.