Red-fleshed apples are the ones with red skin and flesh. They belong to the Red Sun variety derived from commercial cultivation of red-fleshed “Redlove” apples originating in Switzerland, and in Catalonia they are mainly grown in Mollerussa. This red fruit stands out for its high anthocyanin content, a pigment from the flavonoid family that has been associated with beneficial health properties. Research led by investigators at Rovira i Virgili University (URV) and the University of Lleida in partnership with the Eurecat technology centre has revealed the benefits of eating these apples: they enhance endothelial function, reduce inflammation and modulate the immune system in people who have high cholesterol. The results were recently published in the scientific journal Food and Function.
This study, conducted as part of the AppleCOR project and performed at Eurecat’s facilities in Reus, involved 121 people who were divided into three groups: one group ate red-fleshed apples; another ate white-fleshed apples (which do not contain anthocyanins) and the third group consumed an infusion of Aronia melanocarpa, which has anthocyanin content equivalent to red-fleshed apples. The inclusion of this third group made it possible to test whether anthocyanins varied the effect on people’s cardiovascular health depending on whether the anthocyanins were in the apple or the infusion.
After six weeks, the findings suggested that red-fleshed apples improved ischemic reactive hyperaemia, a parameter used to assess endothelial function, and vascular health, which shows how blood vessels dilate in response to the restoration of blood flow. The group of people who consumed red-fleshed apples also had lower levels of C-reactive protein and interleukin-6, both of which are associated with inflammation. There was additionally an improvement in the lipid profile and a reduction in complementary system proteins and immunoglobulins. All these indicators correlate with improved cardiovascular health and reduced chronic inflammation, which may lessen the risk of developing cardiovascular disease, inflammatory disorders and other immune-related conditions.
The anthocyanin-rich Aronia infusion also reduced inflammation and improved lipid profile. However, red-fleshed apples led to greater improvements in inflammation, possibly due to the synergy of anthocyanins with other bioactive compounds present in the apples. In contrast, dietary supplementation with an Aronia infusion enhanced modulation of the lipid profile, which is thought to be related to increased bioavailability of anthocyanins.
The study also found that white-fleshed apples and the Aronia infusion helped improve immune system responses. They did this by modulating the expression of complement system proteins and immunoglobulins, which are key components in the body’s defences against infection.
“The results of this research are significant as they support the evidence for the beneficial effects of anthocyanins from apple consumption on metabolic disorders and cardiovascular health,” says the research team. The data also heighten interest in new naturally biofortified red-fleshed apple crops as a promising and attractive source of bioactive flavanoids with beneficial effects on health.
The researchers taking part in the study were from Rovira i Virgili University, the University of Lleida, Eurecat’s Nutrition and Health Unit and its Centre for Omic Sciences (COS), the Institute of Vine and Wine Sciences (CSIC, University of La Rioja), the Biochemistry and Biotechnology Department in the URV’s Faculty of Medicine and Health Sciences, the Pere Virgili Health Research Institute (IISPV), the CIBER Physiopathology of Obesity and Nutrition (CIBEROBN) and the Biomedical Research Unit at Sant Joan de Reus University Hospital.
References: Pedret A, Companys J, Calderón-Pérez L, Llauradó E, Pla-Pagà L, Salamanca P, Sandoval-Ramírez BA, Catalán Ú, Fernández-Castillejo S, Yuste S, Macià A, Gutiérrez-Tordera L, Bulló M, Camps J, Canela N, Valls RM, Rubió-Piqué L, Motilva MJ, Solà R. A red-fleshed apple rich in anthocyanins improves endothelial function, reduces inflammation, and modulates the immune system in hypercholesterolemic subjects: the AppleCOR study. Food Funct. 2024 Jun 4;15(11):5825-5841. doi: 10.1039/d3fo05114e. PMID: 38751340.
