Changes in liver health biomarkers following consumption of energy restricted diets containing almonds compared with carbohydrate-rich snack foods for 9 months
Energy restricted diets improve liver function(1) and habitual nut consumption has been associated with a lower prevalence of fatty liver(2). This study examined the effect of incorporating almonds in an energy restricted diet on liver health biomarkers. One Hundred and forty adults (42M:98F, 47.5 ± 10.8 years, BMI 30.7 ± 2.3 kg/m2) enrolled in a 9-month (9M) dietary intervention comprising 3 months (3M) weight loss (30% energy restriction) followed by 6 months (6M) of weight maintenance. Participants were randomly assigned to consume almonds (n = 68, AED) or isocaloric carbohydrate-rich snacks (n = 72, CRD) which provided 15% of total daily energy. At baseline (BL), 3M and 9M, fatty liver index (FLI) scores (0-100)(3) were calculated using body mass index (BMI), waist circumference (WC), fasting serum gamma-glutamyl transferase (GGT) and triglyceride (TAG) levels, and other liver health biomarkers were assessed by ultrasound (volume, visual appearance and elastography (a marker of stiffness due to fibrosis)). Intention to treat analyses were conducted using mixed effects modelling (fixed effects group and time, with participants as the random effect). Significant reductions from BL occurred over time (all p<0.001 for 3M and 9M) with no difference between groups (AED vs CRD, P>0.05) in BMI (3M: −2.44 ± 0.20 vs −2.32 ± 0.20, 9M: −2.83 ± 0.19 vs −2.81 ± 0.19 kg/m2), WC (3M: −8.04 ± 0.79 vs −7.00 ± 0.81, 9M: −8.72 ± 0.83 vs −9.14 ± 0.81 cm), TAG (3M: −0.24± 0.08 vs −0.22 ± 0.09, 9M: −0.37 ± 0.09 vs −0.21 ± 0.09 mmol/L), FLI score (3M: −23.8 ± 2.0 vs −17.6 ± 2.1, 9M: −23.8 ± 2.0 vs −17.6 ± 2.1), and liver volume (3M: −134.56 ± 38.30 vs −100.96 ± 37.25, 9M: −113.68 ± 37.42 vs −110.64 ± 35.47cm3). Significantly greater reductions occurred for AED compared to CRD at 3M and 9M in GGT (p = 0.003) (3M: −9.68 ± 1.93 vs −0.01 ± 2.00, 9M: −7.75 ± 2.06 vs −2.78 ± 2.15 IU/L) and liver visual assessment scores (p = 0.03) (3M: −0.58 ± 0.24 vs −0.45 ± 0.23, 9M: −1.33 ± 0.23 vs −0.50 ± 0.22). There were no significant changes in liver elastography over time or between groups. Energy restriction improved body composition and reduced the extent of fatty liver and liver size but did not change liver stiffness. The inclusion of almonds in an energy restricted diet demonstrated additional benefits to some liver health biomarkers providing support for almonds being incorporated into lifestyle interventions to improve liver function. https://doi.org/10.1017/S0029665124000636
Anti-inflammatory effects of the Mediterranean diet: the experience of the PREDIMED study
Several epidemiological and clinical studies have evaluated the effects of a Mediterranean diet (Med-Diet) on total cardiovascular mortality; and all concluded that adherence to the traditional Med-Diet is associated with reduced cardiovascular risk. However; the molecular mechanisms involved are not fully understood. Since atherosclerosis is nowadays considered a low-grade inflammatory disease; recent studies have explored the anti-inflammatory effects of a Med-Diet intervention on serum and cellular biomarkers related to atherosclerosis. In a pilot study of the PREvencion con DIeta MEDiterranea (PREDIMED) trial; we analyzed the short-term effects of two Med-Diet interventions; one supplemented with virgin olive oil and another with nuts; on vascular risk factors in 772 subjects at high risk for CVD; and in a second study we evaluated the effects of these interventions on cellular and serum inflammatory biomarkers in 106 high-risk subjects. Compared to a low-fat diet; the Med-Diet produced favorable changes in all risk factors. Thus; participants in both Med-Diet groups reduced blood pressure; improved lipid profile and diminished insulin resistance compared to those allocated a low-fat diet. In addition; the Med-Diet supplemented with virgin olive oil or nuts showed an anti-inflammatory effect reducing serum C-reactive protein; IL-6 and endothelial and monocytary adhesion molecules and chemokines; whereas these parameters increased after the low-fat diet intervention. In conclusion; Med-Diets down-regulate cellular and circulating inflammatory biomarkers related to atherogenesis in subjects at high cardiovascular risk. These results support the recommendation of the Med-Diet as a useful tool against CVD.