Background: Since the beginning of the COVID-19 pandemic, access to fresh food has been restricted, and people are spending more time inside and have limited their physical activity. However, more time at home may have resulted in some positive habits including an increase in cooking. The aim of this review was to assess dietary changes during the first lockdown. Themes and patterns were considered and associations with other lifestyle factors were assessed.Methods: Between June and July 2020, the PubMed, Google Scholar, and Science Direct databases were searched, and results were screened for eligibility based on title, abstract, and full text. The inclusion criteria of this search included: papers published (or in pre-print) in the year 2020; studies that investigated the impact of COVID-19 lockdown on diet; papers published in English. Exclusion criteria were as follows: papers examining dietary changes in those following a structured diet based on diagnosed conditions or dietetic advice; literature, systematic, or narrative studies reviewing previous research. Researchers agreed on the study characteristics for extraction from final papers.Results: Four thousand three hundred and twenty-two studies were originally considered with 23 final full-text papers included. Four themes were identified: dietary patterns, dietary habits (favorable), dietary habits (unfavorable), and other (includes physical activity levels, weight gain). A total of 10 studies reported an increase in the number of snacks consumed, while six studies found that participants increased their meal number and frequency during quarantine. Eleven studies reported favorable changes in dietary habits with an increase in fresh produce and home cooking and reductions in comfort food and alcohol consumption. However, nine studies found a reduction in fresh produce, with a further six reporting an increase in comfort foods including sweets, fried food, snack foods, and processed foods. Two studies reported an increase in alcohol consumption. In eight studies participants reported weight gain with seven studies reporting a reduction in physical exercise.Conclusion: The effect of COVID-19 lockdown both negatively and positively impacted dietary practices throughout Europe and globally, and negative diet habits were associated with other poor lifestyle outcomes including weight gain, mental health issues, and limited physical activity. Both in the short term and if sustained in the long term, these changes may have significant impacts on the health of the population.

OBJECTIVETo identify, localize, and determine M1/M2 polarization of epidydimal adipose tissue (eAT) macrophages (Φs) during high-fat diet (HFD)-induced obesity.RESEARCH DESIGN AND METHODSMale C57BL/6 mice were fed an HFD (60% fat kcal) or low-fat diet (LFD) (10% fat kcal) for 8 or 12 weeks. eATMΦs (F4/80+ cells) were characterized by in vivo fluorescent labeling, immunohistochemistry, fluorescence-activated cell sorting, and quantitative PCR.RESULTSRecruited interstitial macrophage galactose-type C-type lectin (MGL)1+/CD11c− and crown-like structure–associated MGL1−/CD11c+ and MGL1med/CD11c+ eATMΦs were identified after 8 weeks of HFD. MGL1med/CD11c+ cells comprised ∼65% of CD11c+ eATMΦs. CD11c+ eATMΦs expressed a mixed M1/M2 profile, with some M1 transcripts upregulated (IL-12p40 and IL-1β), others downregulated (iNOS, caspase-1, MCP-1, and CD86), and multiple M2 and matrix remodeling transcripts upregulated (arginase-1, IL-1Ra, MMP-12, ADAM8, VEGF, and Clec-7a). At HFD week 12, each eATMΦ subtype displayed an enhanced M2 phenotype as compared with HFD week 8. CD11c+ subtypes downregulated IL-1β and genes mediating antigen presentation (I-a, CD80) and upregulated the M2 hallmark Ym-1 and genes promoting oxidative metabolism (PGC-1α) and adipogenesis (MMP-2). MGL1med/CD11c+ eATMΦs upregulated additional M2 genes (IL-13, SPHK1, CD163, LYVE-1, and PPAR-α). MGL1med/CD11c+ ATMΦs expressing elevated PGC-1α, PPAR-α, and Ym-1 transcripts were selectively enriched in eAT of obese mice fed pioglitazone for 6 days, confirming the M2 features of the MGL1med/CD11c+ eATMΦ transcriptional profile and implicating PPAR activation in its elicitation.CONCLUSIONSThese results 1) redefine the phenotypic potential of CD11c+ eATMΦs and 2) suggest previously unappreciated phenotypic and functional commonality between murine and human ATMΦs in the development of obesity and its complications.

Adipose tissue (AT) inflammation promotes insulin resistance (IR) and other obesity complications. AT inflammation and IR are associated with oxidative stress, adipocyte death, and the scavenging of dead adipocytes by proinflammatory CD11c+ AT macrophages (ATMPhi). We tested the hypothesis that supplementation of an obesitogenic (high-fat) diet with whole blueberry (BB) powder protects against AT inflammation and IR. Male C57Bl/6j mice were maintained for 8 wk on 1 of 3 diets: low-fat (10% of energy) diet (LFD), high-fat (60% of energy) diet (HFD) or the HFD containing 4% (wt:wt) whole BB powder (1:1 Vaccinium ashei and V. corymbosum) (HFD+B). BB supplementation (2.7% of total energy) did not affect HFD-associated alterations in energy intake, metabolic rate, body weight, or adiposity. We observed an emerging pattern of gene expression in AT of HFD mice indicating a shift toward global upregulation of inflammatory genes (tumor necrosis factor-alpha, interleukin-6, monocyte chemoattractant protein 1, inducible nitric oxide synthase), increased M1-polarized ATMPhi (CD11c+), and increased oxidative stress (reduced glutathione peroxidase 3). This shift was attenuated or nonexistent in HFD+B-fed mice. Furthermore, mice fed the HFD+B were protected from IR and hyperglycemia coincident with reductions in adipocyte death. Salutary effects of BB on adipocyte physiology and ATMPhi gene expression may reflect the ability of BB anthocyanins to alter mitogen-activated protein kinase and nuclear factor-kappaB stress signaling pathways, which regulate cell fate and inflammatory genes. These results suggest that cytoprotective and antiinflammatory actions of dietary BB can provide metabolic benefits to combat obesity-associated pathology.