Dietary raw spinach intake inversely linked to NAFLD: BMC
Several mechanisms have been proposed to explain leafy greens' protective effects, such as spinach on NAFLD. However, it seems that nitrate and polyphenols' contents play a crucial role in this relationship. Supplementing the breakfast with spinach among older women resulted in an increase in the plasma values of polyphenols and carotenoids, including lutein, zeaxanthin, and β-carotene, compared with the control group also higher than strawberries and red wine .
Polyphenols are an important group of bioactive ingredients which a lot of advantageous effects such as hypolipidemic, anti-inflammatory, anti-fibrotic, and insulin-sensitizing properties . It has also been demonstrated that polyphenols inhibit de novo lipogenesis via SREBP1c downregulation and stimulate β-oxidation in the NAFLD models . Nitrate is another important bioactive compound that estimated about 80–95% of its dietary intake supplied through vegetables, mainly green leafy vegetables like spinach . Previous studies have demonstrated that dietary nitrate has protective effects against inflammation and oxidative stress through its ability to activate AMPK via a rise in the xanthine oxidase-dependent NO production, and cGMP signaling declines superoxide levels through NADPH oxidases.
A recent study, published in BMC Gastroenterology, found an inverse association between total and raw spinach intake with the odds of developing nonalcoholic fatty liver disease.
"The present study found an inverse association between total and raw spinach intake with the odds of NAFLD. However, there was no significant association between higher boiled spinach intake and odds of NAFLD."the team highlighted.
Spinach has high antioxidants and polyphenols and showed protective effects against liver diseases in experimental studies. Researchers aimed to assess the association between dietary intake of spinach and odds of nonalcoholic fatty liver disease (NAFLD) in a case–control study among Iranian adults.
For the study design, 225 newly diagnosed NAFLD patients and 450 controls, aged 20–60 years, were recruited in this study. Participants' dietary intakes were collected using a valid and reliable 168-item semi-quantitative food frequency questionnaire (FFQ). The logistic regression test was used for assessing the association between total, raw, and boiled dietary spinach with the odds of NAFLD.
Data analysis revealed the following facts.
- The mean (SD) age and BMI of participants (53% male) were 38.1 (8.8) years and 26.8 (4.3) kg/m2, respectively. In the final adjusted model for potential confounders, the odds (95% CI) of NAFLD in individuals in the highest tertile of daily total and raw spinach intake was [0.36 (0.19–0.71), P_trend = 0.001] and [0.47 (0.24–0.89), P_trend = 0.008], respectively compared with those in the lowest tertile.
- Furthermore, in the adjusted analyses, an inverse association was observed between the highest yearly intake versus no raw spinach consumption and odds of NAFLD [(OR 0.41; 95% CI 0.18–0.96), P for trend = 0.013].
- However, there was no significant association between higher boiled spinach intake and odds of NAFLD.
"Spinach is one of the richest sources of ingredients such as polyphenol and antioxidants. If its beneficial effects on chronic disease are approved in future studies, it could easily be used as a powder to enrich the nutritional values of homemade foods or products such as dairy or other foods. We suggest that our hypothesis of the association between dietary spinach and NAFLD odds be examined in more studies with higher design power, like large cohort studies and clinical trials". the team concluded.
For full article follow the link: https://doi.org/10.1186/s12876-021-01784-8
Primary source: BMC Gastroenterology