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]

1INSERM, U872, équipe 7 Nutriomique, Université Pierre et Marie Curie-Paris 6, Centre de Recherche des Cordeliers, UMR S 872, Paris, 75006 France.
2Centre de Recherche Nutrition Humaine, Ile de France, Assistance Publique-Hôpitaux de Paris, Hôpital Pitié-Salpêtrière, Département de Nutrition et d’Endocrinologie, Paris, 75013 France.

Correspondence
salwa.rizkalla@psl.aphp.fr
Abstract

This paper reviews evidence in the context of current research linking dietary fructose to health risk markers.
Fructose intake has recently received considerable media attention, most of which has been negative. The assertion has been that dietary fructose is less satiating and more lipogenic than other sugars. However, no fully relevant data have been presented to account for a direct link between dietary fructose intake and health risk markers such as obesity, triglyceride accumulation and insulin resistance in humans. First: a re-evaluation of published epidemiological studies concerning the consumption of dietary fructose or mainly high fructose corn syrup shows that most of such studies have been cross-sectional or based on passive inaccurate surveillance, especially in children and adolescents, and thus have not established direct causal links. Second: research evidence of the short or acute term satiating power or increasing food intake after fructose consumption as compared to that resulting from normal patterns of sugar consumption, such as sucrose, remains inconclusive. Third: the results of longer-term intervention studies depend mainly on the type of sugar used for comparison. Typically aspartame, glucose, or sucrose is used and no negative effects are found when sucrose is used as a control group.
Negative conclusions have been drawn from studies in rodents or in humans attempting to elucidate the mechanisms and biological pathways underlying fructose consumption by using unrealistically high fructose amounts.
The issue of dietary fructose and health is linked to the quantity consumed, which is the same issue for any macro- or micro nutrients. It has been considered that moderate fructose consumption of =50g/day or ~10% of energy has no deleterious effect on lipid and glucose control and of =100g/day does not influence body weight. No fully relevant data account for a direct link between moderate dietary fructose intake and health risk markers.