Raisins and increased walking affect lipoprotein metabolism, reduce inflammation and alter satiety hormones

Abstract

Raisins are a significant source of dietary fiber and polyphenols, which may reduce cardiovascular disease (CVD) risk by affecting lipoprotein metabolism and inflammation. Walking represents a low intensity exercise intervention that may also reduce CVD risk. The purpose of this study was to determine the effects of consuming raisins, increasing steps walked, or a combination of these interventions on plasma apolipoproteins and inflammatory cytokines. Thirty‐four men and postmenopausal women were matched for weight and gender and randomly assigned to consume 1 cup raisins/d (RAISIN), increase the amount of steps walked/d (WALK) or a combination of both interventions (RAISIN + WALK). The subjects completed a 2 wk run‐in period, followed by a 6 wk intervention. Plasma apolipoproteins (apo), inflammation markers and appetite hormones were measured at baseline and post‐intervention. Plasma apo CIII was decreased for WALK (P < 0.05), which most likely contributed to the reduction in plasma triglycerides (TG) concentrations from 1.49 mmol/L to 1.2 mmol/L for WALK (P < 0.05 for group effect). Plasma TNF‐α was decreased from 3.5 ng/L to 2.1 ng/L for RAISIN (P < 0.025 for time and group X time effect). All subjects had a reduction in plasma sICAM‐1 (P < 0.01). Plasma ghrelin was increased for both the RAISIN and the RAISIN + WALK groups (P < 0.05), possibly related to an increase in leptin due to raisin intake (P< 0.01). This research shows that simple lifestyle modifications such as adding raisins to the diet or increasing steps walked can alter lipoprotein metabolism and decrease inflammation, resulting in distinct beneficial effects on CVD risk [Supported by the California Raisin Marketing Board]