Viral infections have afflicted human health and despite great advancements in scientific knowledge and technologies, continue to affect our society today. The current coronavirus (COVID-19) pandemic has put a spotlight on the need to review the evidence on the impact of nutritional strategies to maintain a healthy immune system, particularly in instances where there are limited therapeutic treatments. Selenium, an essential trace element in humans, has a long history of lowering the occurrence and severity of viral infections. Much of the benefits derived from selenium are due to its incorporation into selenocysteine, an important component of proteins known as selenoproteins. Viral infections are associated with an increase in reactive oxygen species and may result in oxidative stress. Studies suggest that selenium deficiency alters immune response and viral infection by increasing oxidative stress and the rate of mutations in the viral genome, leading to an increase in pathogenicity and damage to the host. This review examines viral infections, including the novel SARS-CoV-2, in the context of selenium, in order to inform potential nutritional strategies to maintain a healthy immune system.

Iron plays a crucial role in many physiological processes, including oxygen transport, bioenergetics, and immune function. Iron is assimilated from food and also recycled from senescent red blood cells. Iron exists in two dietary forms: heme (animal based) and non-heme (mostly plant based). The body uses iron for metabolic purposes, and stores the excess mainly in splenic and hepatic macrophages. Physiologically, iron excretion in humans is inefficient and not highly regulated, so regulation of intestinal absorption maintains iron homeostasis. Iron losses occur at a steady rate via turnover of the intestinal epithelium, blood loss, and exfoliation of dead skin cells, but overall iron homeostasis is tightly controlled at cellular and systemic levels. Aging can have a profound impact on iron homeostasis and induce a dyshomeostasis where iron deficiency or overload (sometimes both simultaneously) can occur, potentially leading to several disorders and pathologies. To maintain physiologically balanced iron levels, reduce risk of disease, and promote healthy aging, it is advisable for older adults to follow recommended daily intake guidelines and periodically assess iron levels. Clinicians can evaluate body iron status using different techniques but selecting an assessment method primarily depends on the condition being examined. This review provides a comprehensive overview of the forms, sources, and metabolism of dietary iron, associated disorders of iron dyshomeostasis, assessment of iron levels in older adults, and nutritional guidelines and strategies to maintain iron balance in older adults.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent liver disease in the United States. Food-insecure individuals often depend on low-cost, energy-dense but nutritionally poor foods, resulting in obesity and chronic diseases related to NAFLD. To determine whether food insecurity is associated with NAFLD in a cohort of HIV and hepatitis C virus (HCV) infected and uninfected adults. We conducted a cross-sectional analysis of low-income, middle-aged adults from the Miami Adult Studies on HIV (MASH) cohort without a history of excessive alcohol consumption. Food security was assessed with the USDA's Household Food Security Survey. MRIs were used to assess liver steatosis and fibrosis. Metabolic parameters were assessed from fasting blood, anthropometrics, and vitals. Of the total 603 participants, 32.0% reported food insecurity. The prevalences of NAFLD, fibrosis, and advanced fibrosis were 16.1%, 15.1%, and 4.6%, respectively. For every 5 kg/m2 increase in BMI, the odds of NAFLD increased by a factor of 3.83 (95% CI, 2.37-6.19) in food-insecure participants compared to 1.32 (95% CI, 1.04-1.67) in food-secure participants. Food insecurity was associated with increased odds for any liver fibrosis (OR, 1.65; 95% CI, 1.01-2.72) and advanced liver fibrosis (OR, 2.82; 95% CI, 1.22-6.54), adjusted for confounders. HIV and HCV infections were associated with increased risks for fibrosis, but the relationship between food insecurity and liver fibrosis did not differ between infected and uninfected participants. Among low-income, middle-aged adults, food insecurity exacerbated the risk for NAFLD associated with a higher BMI and independently increased the risk for advanced liver fibrosis. People who experience food insecurity, particularly those vulnerable to chronic diseases and viral infections, may be at increased risk for liver-related morbidity and mortality. Improving access to adequate nutrition and preventing obesity among low-income groups may lessen the growing burden of NAFLD and other chronic diseases.

Background: Socioeconomic disadvantages and potential immunocompromise raise particular concerns for people living with HIV (PLWH) and other marginalized communities during the COVID-19 pandemic. In this study, we explored COVID-19 testing and the impact of the pandemic among participants from the Miami Adult Studies on HIV cohort, predominantly composed of low-income minorities living with and without HIV. Methods: Between July and August 2020, a telephone survey was administered to 299 Miami Adult Studies on HIV participants to assess COVID-19 testing, prevention behaviors, and psychosocial stressors. Health care utilization, antiretroviral adherence, food insecurity, and substance use during the pandemic were compared with those of their last cohort visit (7.8 ± 2.9 months earlier). Results: Half of surveyed participants had been tested for COVID-19, 8 had tested positive and 2 had been hospitalized. PLWH (n = 183) were 42% times less likely than HIV-uninfected participants to have been tested. However, after adjustment for age, employment, COVID-19 symptoms, mental health care, and substance use, the effect of HIV status was no longer significant. PLWH were more likely to have seen a health care provider, use face coverings, and avoid public transportation and less likely to be food insecure and drink hazardously. There were significant changes in substance use patterns during the pandemic when compared with those before. Conclusion: PLWH, compared with their HIV-uninfected peers, were more likely to engage in preventive measures and health care during the pandemic, potentially reducing their exposure to COVID-19. There were no reported changes in antiretroviral adherence or health care utilization, but there were changes in substance use; these need to be monitored as this crisis progresses.

Objective: This study evaluated whether food insecurity (US Adult Food Security Survey) was associated with chronic pain (≥ 3 months) and high-impact chronic pain (i.e. pain that limits work and life) among US adults. Design: Cross-sectional analysis. Setting: Nationally representative sample of non-institutionalised adults in the USA. Participants: 79 686 adults from the National Health Interview Survey (2019–2021). Results: Marginal, low and very low food security were associated with increased prevalence odds of chronic pain (OR: 1·58 (95 % CI 1·44, 1·72), 2·28 (95 % CI 2·06, 2·52) and 3·37 (95 % CI 3·01, 3·78), respectively) and high-impact chronic pain (OR: 1·28 (95 % CI 1·14, 1·42), 1·55 (95 % CI 1·37, 1·75) and 1·90 (95 % CI 1·65, 2·18), respectively) in a dose–response fashion (P-trend < 0·0001 for both), adjusted for sociodemographic, socio-economic and clinically relevant factors. Participation in Supplemental Nutrition Assistance Program (SNAP) and age modified the association between food insecurity and chronic pain. Conclusions: These findings illustrate the impact of socio-economic factors on chronic pain and suggest that food insecurity may be a social determinant of chronic pain. Further research is needed to better understand the complex relationship between food insecurity and chronic pain and to identify targets for interventions. Moreover, the consideration of food insecurity in the clinical assessment of pain and pain-related conditions among socio-economically disadvantaged adults may be warranted.