The Longevity Project » diet

Accruing evidence on benefits of adherence to the Mediterranean diet on health: an updated systematic review and meta-analysis.

CL — Sun, 27 Feb 2011 10:41:52 +0000

Am J Clin Nutr. 2010 Nov;92(5):1189-96. Epub 2010 Sep 1.

Sofi F, Abbate R, Gensini GF, Casini A.

Department of Medical and Surgical Critical Care, Thrombosis Centre, University of Florence, Florence, Italy. francescosofi@gmail.com

Abstract
BACKGROUND: The Mediterranean diet has long been reported to be protective against the occurrence of several different health outcomes.

OBJECTIVE: We aimed to update our previous meta-analysis of published cohort prospective studies that investigated the effects of adherence to the Mediterranean diet on health status.

DESIGN: We conducted a comprehensive literature search through electronic databases up to June 2010.

RESULTS: The updated review process showed 7 prospective studies published in the past 2 y that were not included in the previous meta-analysis (1 study for overall mortality, 3 studies for cardiovascular incidence or mortality, 1 study for cancer incidence or mortality, and 2 studies for neurodegenerative diseases). These recent studies included 2 health outcomes not previously investigated (ie, mild cognitive impairment and stroke). The meta-analysis for all studies with a random-effects model that was conducted after the inclusion of these recent studies showed that a 2-point increase in adherence to the Mediterranean diet was associated with a significant reduction of overall mortality [relative risk (RR) = 0.92; 95% CI: 0.90, 0.94], cardiovascular incidence or mortality (RR = 0.90; 95% CI: 0.87, 0.93), cancer incidence or mortality (RR = 0.94; 95% CI: 0.92, 0.96), and neurodegenerative diseases (RR = 0.87; 95% CI: 0.81, 0.94). The meta-regression analysis showed that sample size was the most significant contributor to the model because it significantly influenced the estimate of the association for overall mortality.

CONCLUSION: This updated meta-analysis confirms, in a larger number of subjects and studies, the significant and consistent protection provided by adherence to the Mediterranean diet in relation to the occurrence of major chronic degenerative diseases.

PMID: 20810976 [PubMed - indexed for MEDLINE]

Brain functional magnetic resonance imaging response to glucose and fructose infusions in humans.

CL — Sun, 27 Feb 2011 10:23:40 +0000

Diabetes Obes Metab. 2011 Mar;13(3):229-34. doi: 10.1111/j.1463-1326.2010.01340.x.

Purnell JQ, Klopfenstein BA, Stevens AA, Havel PJ, Adams SH, Dunn TN, Krisky C, Rooney WD.

Department of Medicine, Oregon Health & Science University, Portland, OR, USA. purnellj@ohsu.edu

Abstract
AIMS: In animals, intracerebroventricular glucose and fructose have opposing effects on appetite and weight regulation. In humans, functional brain magnetic resonance imaging (fMRI) studies during glucose ingestion or infusion have demonstrated suppression of hypothalamic signalling, but no studies have compared the effects of glucose and fructose. We therefore sought to determine if the brain response differed to glucose vs. fructose in humans independently of the ingestive process.

METHODS: Nine healthy, normal weight subjects underwent blood oxygenation level dependent (BOLD) fMRI measurements during either intravenous (IV) glucose (0.3 mg/kg), fructose (0.3 mg/kg) or saline, administered over 2 min in a randomized, double-blind, crossover study. Blood was sampled every 5 min during a baseline period and following infusion for 60 min in total for glucose, fructose, lactate and insulin levels.

RESULTS: No significant brain BOLD signal changes were detected in response to IV saline. BOLD signal in the cortical control areas increased during glucose infusion (p = 0.002), corresponding with increased plasma glucose and insulin levels. In contrast, BOLD signal decreased in the cortical control areas during fructose infusion (p = 0.006), corresponding with increases of plasma fructose and lactate. Neither glucose nor fructose infusions significantly altered BOLD signal in the hypothalamus.

CONCLUSION: In normal weight humans, cortical responses as assessed by BOLD fMRI to infused glucose are opposite to those of fructose. Differential brain responses to these sugars and their metabolites may provide insight into the neurologic basis for dysregulation of food intake during high dietary fructose intake.

Dietary pattern and depressive symptoms in middle age

TLP — Thu, 05 Nov 2009 15:12:36 +0000

BACKGROUND: Studies of diet and depression have focused primarily on individual nutrients. AIMS: To examine the association between dietary patterns and depression using an overall diet approach. METHOD: Analyses were carried on data from 3486 participants (26.2% women, mean age 55.6 years) from the Whitehall II prospective cohort, in which two dietary patterns were identified: ‘whole food’ (heavily loaded by vegetables, fruits and fish) and ‘processed food’ (heavily loaded by sweetened desserts, fried food, processed meat, refined grains and high-fat dairy products). Self-reported depression was assessed 5 years later using the Center for Epidemiologic Studies – Depression (CES-D) scale. RESULTS: After adjusting for potential confounders, participants in the highest tertile of the whole food pattern had lower odds of CES-D depression (OR = 0.74, 95% CI 0.56-0.99) than those in the lowest tertile. In contrast, high consumption of processed food was associated with an increased odds of CES-D depression (OR = 1.58, 95% CI 1.11-2.23). CONCLUSIONS: In middle-aged participants, a processed food dietary pattern is a risk factor for CES-D depression 5 years later, whereas a whole food pattern is protective.

Br J Psychiatry. 2009 Nov;195(5):408-13.

Akbaraly TN, Brunner EJ, Ferrie JE, Marmot MG, Kivimaki M, Singh-Manoux A.

Department of Epidemiology and Public Health, University College London, London WC1E 6BT, UK. tasnime.akbaraly@inserm.fr

Diet, lifestyle and risk of prostate cancer

TLP — Tue, 03 Jul 2007 18:22:41 +0000

Prostate cancer has become a major public health problem worldwide. Yet, the etiology of prostate cancer remains largely unknown. Dietary factors, dietary supplements, and physical activity might be important in the prevention of the disease. In the majority of studies, it was observed that high consumption of meat and dairy products has been linked to a greater risk. In contrast, frequent consumption of fatty fish and tomato products has been associated with a reduced risk. It has been shown consistently that high levels of circulating insulin-like growth factor 1 (IGF-1) are associated with an increased risk of prostate cancer. Dietary factors are also recognized as determinants of circulating IGF-1, thus changes in diet may influence IGF-1 concentrations in serum. Furthermore, increased intake of vitamin E and selenium (from supplements) has been shown in intervention studies to decrease the risk. Possibly, high level of physical activity is also associated with decreased risk of prostate cancer. The accumulated scientific evidence concerning the associations between diet, lifestyle, and risk of prostate cancer development suggests that there are some identified modifiable risk factors that it might be recommended to change in order to decrease the risk for this common cancer site.

Wolk A.

Division of Nutritional Epidemiology, the National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden. Alicja.Wolk@imm.ki.se

Acta Oncol. 2005;44(3):277-81.Links