1.
The Impact of COVID-19-Related Living Restrictions on Eating Behaviours in Children and Adolescents: A Systematic Review.
Brakspear, L, Boules, D, Nicholls, D, Burmester, V
Nutrients. 2022;(17)
Abstract
The COVID-19 pandemic prompted the imposition of physical and social distancing measures worldwide. Emerging data suggest that younger age groups may be particularly vulnerable to the adverse mental health impacts of the pandemic. Since the start of the COVID-19 pandemic, there has been an unprecedented increase in demand for child and adolescent eating disorder services. The aim of this review was to systematically review and appraise the current literature on the impact of COVID-19-related living restrictions on the eating behaviours of children and adolescents. Searches of eight electronic databases were conducted in March 2021 and December 2021 for published and grey literature on eating behaviours of population samples of children and adolescents (aged 18 months to 18 years old) who were exposed to COVID-19-related living restrictions. Of 3165 retrieved references, sixteen studies were included in this review, comprising data from 125, 286 participants. There was a pattern towards healthier eating behaviours among children and adolescents during the COVID-19 lockdown. However, young people from lower socioeconomic groups showed a tendency towards more unhealthy eating behaviours, and there was an association between mood difficulties and greater changes in eating; this suggests that such groups may be more vulnerable to the adverse health consequences of lockdowns.
2.
Review of eating disorders and oxytocin receptor polymorphisms.
Burmester, V, Nicholls, D, Buckle, A, Stanojevic, B, Crous-Bou, M
Journal of eating disorders. 2021;(1):85
Abstract
BACKGROUND AND AIMS Oxytocin, a nine amino acid peptide synthesised in the hypothalamus, has been widely recognised for its role in anxiolysis, bonding, sociality, and appetite. It binds to the oxytocin receptor (OXTR)-a G-protein coupled receptor-that is stimulated by the actions of oestrogen both peripherally and centrally. Studies have implicated OXTR genotypes in conferring either a risk or protective effect in autism, schizophrenia, and eating disorders (ED). There are numerous DNA variations of this receptor, with the most common DNA variation being in the form of the single nucleotide polymorphisms (SNPs). Two OXTR SNPs have been most studied in relation to ED: rs53576 and rs2254298. Each SNP has the same allelic variant that produces genotypes AA, AG, and GG. In this critical review we will evaluate the putative role of rs53576 and rs2254298 SNPs in ED. Additionally, this narrative review will consider the role of gene-environment interactions in the development of ED pathology. FINDINGS The OXTR SNPs rs53576 and rs2254298 show independent associations between the A allele and restrictive eating behaviours. Conversely, the G allele of the OXTR rs53576 SNP is associated with binging behaviours, findings that were also evident in neuroanatomy. One study found the A allele of both OXTR SNPs to confer risk for more severe ED symptomatology while the G allele conferred some protective effect. An interaction between poor maternal care and rs2254298 AG/AA genotype conferred increased risk for binge eating and purging in women. CONCLUSIONS Individual OXTR SNP are unlikely in themselves to explain complex eating disorders but may affect the expression of and/or effectiveness of the OXTR. A growing body of G x E work is indicating that rs53576G homozygosity becomes disadvantageous for later mental health under early adverse conditions but further research to extend these findings to eating pathology is needed. The GWAS approach would benefit this area of knowledge.
3.
Oxytocin reduces post-stress sweet snack intake in women without attenuating salivary cortisol.
Burmester, V, Gibson, EL, Butler, G, Bailey, A, Terry, P
Physiology & behavior. 2019;:112704
Abstract
Intranasal oxytocin produces anorectic effects on snack intake in men when tested in the absence of deprivation-induced hunger, but its effects on food intake in women without eating disorders have not been reported. Oxytocin may reduce food intake by reducing stress eating, since it inhibits ACTH release. The present study adopted a double-blind, repeated measures and fully concealed crossover protocol in which 38 women self-administered 24 IU of oxytocin or placebo intranasally, ate lunch, and underwent two consecutive stress tests. Snack intake was assessed 15-20 min after lunch, via a sham taste test. Salivary cortisol was measured throughout the test period every 15 min. Oxytocin significantly reduced sweet fatty snack intake independently of any effect on salivary cortisol, which declined over time at a similar rate after either drug or placebo. Ratings of sweet taste were slightly reduced by oxytocin, but only in self-reported stress eaters. These results differ from previous studies with men that found an effect of oxytocin on postprandial cortisol levels. However, previous research assayed the less active form of plasma cortisol and did not control for protein intake, which can drive elevated cortisol. The finding that oxytocin reduces snack intake in females after acute stress has important implications for appetite regulation and its treatment in obese people and in those with eating disorders.
4.
Rapid-onset anorectic effects of intranasal oxytocin in young men.
Burmester, V, Higgs, S, Terry, P
Appetite. 2018;:104-109
Abstract
Although the neuropeptide oxytocin exhibits many of the characteristics that would support its use as an anorectic agent for overeaters, studies of oxytocin's effectiveness at reducing eating in humans remain limited. In a double-blind, placebo-controlled crossover study, under the pretext of examining oxytocin's effects on various aspects of sensory perception, 20 men were given 24 IU of oxytocin and took a taste test of sweet, salty, and neutral snacks 45 min later. Participants self-rated appetite, anxiety, and other mood parameters, and then were left alone for 10 min with the pre-weighed snack food and invited to help themselves. To minimize the influence of hunger-driven eating, lunch had been provided immediately after oxytocin administration. In line with Ott et al. (2013), oxytocin significantly reduced the consumption of sweet foods; however, it also reduced consumption of salty snacks. Self-reported anxiety did not differ across drug conditions. The study is the first to demonstrate an effect of oxytocin on snack eating at 45 min post administration and on salty snacks. The anorectic efficacy of oxytocin after 45 min cannot easily be explained by the same mechanism as the one presumed to underpin its effects in previous studies that adopted much longer intervals between drug administration and testing.