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In this population, among those who progressed to dementia, 60% progressed to AD and 33% to VaD. Vascular risk factors influence incident mild cognitive impairment and the rate of progression to dementia.

Effect of satiation on brain activity in obese and lean women. Obes Res. 2001;9:676 -684. Objective: To investigate the response of the brains of women to the ingestion of a meal. Research Methods and Procedures:We used measures of regional cerebral blood flow (rCBF), a marker of neuronal activity, by positron emission tomography to describe the functional anatomy of satiation, i.e., the response to a liquid meal in the context of extreme hunger (36-hour fast) in 10 lean (BMI Յ 25 kg/m 2 ; 32 Ϯ 10 years old, 61 Ϯ 7 kg; mean Ϯ SD) and 12 obese (BMI Ն 35 kg/m 2 ; 30 Ϯ 7 years old, 110 Ϯ 14 kg) women. Results: In lean and obese women, satiation produced significant increases in rCBF in the vicinity of the prefrontal cortex (p Ͻ 0.005). Satiation also produced significant decreases in rCBF in several regions including the thalamus, insular cortex, parahippocampal gyrus, temporal cortex, and cerebellum (in lean and obese women), and hypothalamus, cingulate, nucleus accumbens, and amygdala (in obese women only; all p Ͻ 0.005). Compared with lean women, obese women had significantly greater increases in rCBF in the ventral prefrontal cortex and had significantly greater decreases in the paralimbic areas and in areas of the frontal and temporal cortex.Discussion: This study indicates that satiation elicits differential brain responses in obese and lean women. It also lends additional support to the hypothesis that the paralimbic areas participate in a central orexigenic network modulated by the prefrontal cortex through feedback loops.

BACKGROUND:Obesity results from a chronic imbalance between energy intake and energy expenditure. However, experimental evidence of the relative contribution of interindividual differences in energy intake and expenditure (resting or due to physical activity) to weight gain is limited. OBJECTIVE: To assess prospectively the association between baseline measurements of daily energy metabolism and weight changes by studying free-living adult Pima Indians, one of the most obese populations in the world. DESIGN: A study of the pathogenesis of obesity in the Pima Indians living in Southwestern Arizona. The participants were 92 nondiabetic Pima Indians (64M/28F, 35712 y, 3579% body fat; mean7s.d.). At baseline, free-living daily energy metabolism was assessed by doubly labeled water and resting metabolic rate (RMR) by indirect calorimetry. Data on changes in body weight (5.876.5 kg) over a follow-up period of 473 y were available in 74 (49M/25F) of the 92 subjects. RESULTS: The baseline calculated total energy intake (r ¼ 0.25, P ¼ 0.028) and RMR (r ¼ À0.28, P ¼ 0.016) were significantly associated with changes in body weight. The baseline energy expenditure due to physical activity was not associated with changes in body weight. CONCLUSION: Using state-of-the-art methods to assess energy intake and expenditure in free-living conditions, we show for the first time that the baseline calculated total energy intake is a determinant of changes in body weight in Pima Indians. These data also confirm that a low RMR is a risk factor for weight gain in this population.

Because the dorsolateral prefrontal cortex has been implicated in the inhibition of inappropriate behavior, satiety, and meal termination, differential responses of neuronal activity to food intake in this area may contribute to a propensity for obesity or to the difficulty in losing weight experienced by obese men.

These results suggest that SWLs show greater activation in frontal regions and primary and secondary visual cortices-a pattern consistent with greater inhibitory control in response to food cues and greater visual attention to the food cues. A greater engagement of inhibitory control regions in response to food cues as well as a greater monitoring of foods may promote control of food intake and successful weight-loss maintenance.

In an elderly population of Southern Italy with a typical Mediterranean diet, high MUFA intakes appeared to be protective against age-related cognitive decline. Prospective clinical trials are needed to evaluate the impact of specific dietary macronutrient intakes on the age-related changes of cognitive functions.

Objective: To investigate the possible role of diet in age-related cognitive decline (ARCD) and cognitive impairment of both degenerative (Alzheimer's disease, AD) and vascular (vascular dementia, VaD) origin. Design: Literature review. Results:In an elderly population of southern Italy with a typical Mediterranean diet, high energy intake of monounsaturated fatty acids (MUFA) appeared to be associated with a high level of protection against ARCD. In addition, dietary fat and energy in the elderly seem to be risk factors, while fish consumption and cereals are found to reduce the prevalence of AD in European and North American countries. Finally, the relative risk of dementia (AD and VaD) was lower in the subjects of a French cohort who drank three or four glasses of red wine each day compared with total abstainers.