Higher flavonoid intake is associated with a lower progression risk of non-alcoholic fatty liver disease in adults: a prospective study.

Zhong, Qing-Wei; Wu, Yan-Yan; Xiong, Feng; Liu, Meng; Liu, Yu-Ping; Wang, Cheng; Chen, Yu-Ming

Flavonoid-rich foods have shown a beneficial effect against non-alcoholic fatty liver disease (NAFLD) in short-term randomized trials and animal experiments. It is uncertain whether the usual dietary intake of flavonoids may benefit patients with NAFLD. This study evaluated the association between the usual intake of total flavonoids and their subclasses and the risk of progression in NAFLD. The prospective study included 2694 adults from the Guangzhou Nutrition & Health Study. Face-to-face interviews using a 79-item food frequency questionnaire were administered to assess habitual dietary flavonoid intake, while abdominal ultrasonography was conducted to evaluate the presence and degree of NAFLD, with measurements conducted three years apart. After adjustment for potential confounders, higher flavonoid intakes were gradely associated with reduced risks of worsen NAFLD status. The relative risks (95% CI) of worsening (vs. non-worsening) NAFLD in the highest (vs. lowest) quintile were 0.71 (0.54, 0.93) for total flavonoids, 0.74 (0.57, 0.95) for flavanones, 0.74 (0.56, 0.96) for flavan-3-ols, 0.90 (0.68, 1.18) for flavonols, 0.73 (0.56, 0.93) for flavones, 0.79 (0.61, 1.02) for isoflavones and 0.74 (0.57, 0.96) for anthocyanins. Sub-group analysis found that the beneficial associations were evident only in overweight/obese participants (P-interactions=0.015). An L-shaped (non-linear) relationship was observed between total flavonoid intake and the risk of NAFLD progression. Path analyses showed that the association between flavonoids and NAFLD progression was mediated by decreases in serum cholesterol and HOMA-IR. This prospective study showed that higher flavonoids intake was associated with a lower risk of NAFLD progression in the elderly overweight/obese Chinese population.