Functional and nutraceutical foods provide an alternative way to improve immune function to aid in the management of various diseases. Traditionally, many medicinal products have been derived from natural compounds with healing properties. With the development of research into nutraceuticals, it is becoming apparent that many of the beneficial properties of these compounds are at least partly due to the presence of polyphenols. There is evidence that dietary polyphenols can influence dendritic cells, have an immunomodulatory effect on macrophages, increase proliferation of B cells, T cells and suppress Type 1 T helper (Th1), Th2, Th17 and Th9 cells. Polyphenols reduce inflammation by suppressing the pro-inflammatory cytokines in inflammatory bowel disease by inducing Treg cells in the intestine, inhibition of tumor necrosis factor-alpha (TNF-α) and induction of apoptosis, decreasing DNA damage. Polyphenols have a potential role in prevention/treatment of auto-immune diseases like type 1 diabetes, rheumatoid arthritis and multiple sclerosis by regulating signaling pathways, suppressing inflammation and limiting demyelination. In addition, polyphenols cause immunomodulatory effects against allergic reaction and autoimmune disease by inhibition of autoimmune T cell proliferation and downregulation of pro-inflammatory cytokines (interleukin-6 (IL-6), IL-1, interferon-γ (IFN-γ)). Herein, we summarize the immunomodulatory effects of polyphenols and the underlying mechanisms involved in the stimulation of immune responses.

The coronavirus disease is still spreading in the United Arab Emirates (UAE) with subsequent lockdowns and social distancing measures being enforced by the government. The purpose of this study was to assess the effect of the lockdown on eating habits and lifestyle behaviors among residents of the UAE. A cross-sectional study among adults in the UAE was conducted using an online questionnaire between April and May 2020. A total of 1012 subjects participated in the study. During the pandemic, 31% reported weight gain and 72.2% had less than eight cups of water per day. Furthermore, the dietary habits of the participants were distanced from the Mediterranean diet principles and closer to “unhealthy” dietary patterns. Moreover, 38.5% did not engage in physical activity and 36.2% spent over five hours per day on screens for entertainment. A significantly higher percentage of participants reported physical exhaustion, emotional exhaustion, irritability, and tension “all the time” during the pandemic compared to before the pandemic (p < 0.001). Sleep disturbances were prevalent among 60.8% of the participants during the pandemic. Although lockdowns are an important safety measure to protect public health, results indicate that they might cause a variety of lifestyle changes, physical inactivity, and psychological problems among adults in the UAE.

The COVID-19 pandemic is a major health crisis that has changed the life of millions globally. The purpose of this study was to assess the effect of the pandemic on mental health and quality of life among the general population in the Middle East and North Africa (MENA) region. A total of 6142 adults from eighteen countries within the MENA region completed an online questionnaire between May and June 2020. Psychological impact was assessed using the Impact of Event Scale-Revised (IES-R) and the social and family support impact was assessed with questions from the Perceived Support Scale (PSS). The IES-R mean score was 29.3 (SD = 14.8), corresponding to mild stressful impact with 30.9% reporting severe psychological impact. Most participants (45%–62%) felt horrified, apprehensive, or helpless due to COVID-19. Furthermore, over 40% reported increased stress from work and financial matters. Higher IES-R scores were found among females, participants aged 26–35 years, those with lower educational level, and participants residing in the North Africa region (p<0.005). About 42% reported receiving increased support from family members, 40.5% were paying more attention to their mental health, and over 40% reported spending more time resting since the pandemic started. The COVID-19 pandemic was associated with mild psychological impact while it also encouraged some positive impact on family support and mental health awareness among adults in the MENA region. Clinical interventions targeted towards vulnerable groups such as females and younger adults are needed.