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Dietetics, Nutrition and Biological Sciences

Permanent URI for this collectionhttps://eresearch.qmu.ac.uk/handle/20.500.12289/23

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Start date: 1990Subject: search.filters.subject.Obesity

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Now showing 1 - 5 of 5
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    Polyphenol supplementation and executive functioning in overweight and obese adults at risk of cognitive impairment: A systematic review and meta-analysis
    (Public Library of Science, 2023-05-25) Farag, Sara; Tsang, Catherine; Murphy, Philip N.
    Background and objectives Increasing evidence indicates a link between obesity and cognitive impairment. Furthermore, there is limited literature regarding the effect of polyphenols, a plant derived compounds, on executive functioning in an overweight/obese population at-risk of cognitive impairment. The aim of the present systematic review and meta-analysis of randomized controlled trials is to examine the effect of polyphenol supplementation on executive functions in overweight and/or obese populations at risk of cognitive impairment. Methods A comprehensive literature search was conducted from inception to March 2023 using four electronic databases: PubMed/Medline, PsycInfo, Scopus and Cochrane trials library. Published primary research studies in English that compared the effect of polyphenols with placebo on executive function in overweight/obese adults were considered eligible for the meta-analysis. Jadad scale was used for the methodological quality rating of the included studies. Hedges g with 95% confidence intervals (CI) for endpoints were calculated using random effect model where applicable. Rosenthal’s Fail-safe N, funnel plots, the Begg and Mazumdar’s rank correlation test (Kendall’s S statistic P-Q), Egger’s linear regression test, and Duval and Tweedie’s trim-and-fill test were identified for potential use as appropriate, to examine publication bias. Sensitivity analysis was conducted to examine the robustness of the results. Results and conclusion A total of 23 RCT studies involving N = 1,976 participants were included in the review. The results of the meta-analysis revealed a non-significant effect for polyphenol supplementation on executive function (g = 0.076, CI = -0.018 to 0.170). Observations from primary studies within the meta-analysis showed a potential positive effect of polyphenol supplementation in a younger population at-risk of cognitive impairment and it is recommended to investigate this further in future studies. Moreover, the variability of the tasks used to examine executive functions as well as the adequate reporting of supplement’s phenolic composition is a limitation that future work should also consider.
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    Effect of Polyphenol Supplementation on Memory Functioning in Overweight and Obese Adults: A Systematic Review and Meta-Analysis
    (MDPI, 2024-02-06) Farag, Sara; Tsang, Catherine; Al-Dujaili, Emad A. S.; Murphy, Philip N.
    Negative health consequences of obesity include impaired neuronal functioning and cell death, thus bringing the risk of impaired cognitive functioning. Antioxidant properties of polyphenols offer a possible intervention for overweight people, but evidence for their effectiveness in supporting cognitive functioning is mixed. This review examined evidence from randomized controlled trials concerning the effect of polyphenols on tasks requiring either immediate or delayed retrieval of learned information, respectively, thus controlling for differences in cognitive processes and related neural substrates supporting respective task demands. Searches of the PubMed/Medline, PsycInfo, and Scopus databases identified 24 relevant primary studies with N = 2336 participants having a BMI ≥ 25.0 kg/m2. The participants’ mean age for the 24 studies exceeded 60 years. Respective meta-analyses produced a significant summary effect for immediate retrieval but not for delayed retrieval. The present findings support a potential positive effect of chronic supplementation with polyphenols, most notably flavonoids, on immediate retrieval in participants aged over 60 years with obesity being a risk factor for cognitive impairment. We recommend further investigation of this potential positive effect in participants with such risk factors. Future research on all populations should report the phenolic content of the supplementation administered and be specific regarding the cognitive processes tested.
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    Prenatal programming of postnatal obesity: fetal nutrition and the regulation of leptin synthesis and secretion before birth
    (Cambridge University Press, 2004-08) Davidson, Isobel; Smith, Sara
    The introduction of the process of nutritional screening into clinical standards has been driven by the increasing awareness of the prevalence of undernutrition in acute and primary care, along with its associated morbidity and mortality. However, the increasing prevalence of obesity in the general population suggests that an increased number of patients admitted to hospital will be obese. Increased morbidity has also been reported in the injured obese patient and may be associated with poor nutritional support. This situation may occur because the profound metabolic disturbances accompanying trauma in this group are not recognised, and subsequent feeding practices are inappropriate. Screening tools currently classify patients by using simple markers of assessment at the whole-body level, such as BMI. Subsequently, patients are identified as at risk only if they are undernourished. Such comparisons would by definition classify injured obese patients as at minimal or no nutritional risk, and they would therefore be less likely to be re-screened. This approach could result in potential increases in morbidity, length of rehabilitation and consequent length of hospital stay. It is likely that the identification of potential risk in obese injured patients goes beyond the measurement of such indices as BMI and percentage weight loss, which are currently utilised by the majority of screening processes.
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    Intake of polyphenol-rich pomegranate pure juice influences urinary glucocorticoids, blood pressure and homeostasis model assessment of insulin resistance in human volunteers
    (2012-08) Tsang, Catherine; Smail, Nacer Foudil; Almoosawi, Suzana; Davidson, Isobel; Al-Dujaili, Emad A. S.
    Pomegranate juice (PJ; also known as pomegreat pure juice) provides a rich and varied source of polyphenolic compounds that may offer cardioprotective, anti-atherogenic and antihypertensive effects. The aim of this study was to investigate the effect of PJ consumption on glucocorticoids levels, blood pressure (BP) and insulin resistance in volunteers at high CVD risk. Subjects (twelve males and sixteen females) participated in a randomised, placebo-controlled cross-over study (BMI: 2677 (sd 336) kg/m2; mean age: 504 (sd 61) years). Volunteers were assessed at baseline, and at weeks 2 and 4 for anthropometry, BP and pulse wave velocity. Cortisol and cortisone levels in urine and saliva were determined by specific ELISA methods, and the cortisol/cortisone ratio was calculated. Fasting blood samples were obtained to assess plasma lipids, glucose, insulin and insulin resistance (homeostasis model assessment of insulin resistance). Volunteers consumed 500 ml of PJ or 500 ml of a placebo drink containing a similar amount of energy. Cortisol urinary output was reduced but not significant. However, cortisol/cortisone ratios in urine (P = 0009) and saliva (P = 0024) were significantly decreased. Systolic BP decreased from 1364 (sd 63) to 1289 (sd 51) mmHg (P = 0034), and diastolic BP from 803 (sd 429) to 755 (sd 517) mmHg (P = 0031) after 4 weeks of fruit juice consumption. Pulse wave velocity decreased from 75 (sd 086) to 744 (sd 094) m/s (P = 0035). There was also a significant reduction in fasting plasma insulin from 936 (sd 58) to 753 (sd 412) mIU/l (P = 0025) and of homeostasis model assessment of insulin resistance (from 2216 (sd 143) to 182 (sd 112), P = 0028). No significant changes were seen in the placebo arm of the study. These results suggest that PJ consumption can alleviate key cardiovascular risk factors in overweight and obese subjects that might be due to a reduction in both systolic and diastolic BP, possibly through the inhibition of 11_-hydroxysteroid dehydrogenase type 1 enzyme activity as evidenced by the reduction in the cortisol/cortisone ratio. The reduction in insulin resistance might have therapeutic benefits for patients with non-insulin-dependent diabetes, obesity and the metabolic syndrome.
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    Effectiveness of nutritional and exercise interventions to improve body composition and muscle strength or function in sarcopenic obese older adults: A systematic review
    (Elsevier, 2017-05-11) Theodorakopoulos, Christos; Jones, Jacklyn; Bannerman, Elaine; Greig, Carolyn
    Although sarcopenic obesity (SO) poses a major public health concern, a robust approach for the optimization of body composition and strength/function in SO has not yet been established. The purpose of this systematic review was to assess the effectiveness of nutritional (focusing on energy and protein modulation) and exercise interventions, either individually or combined, on body composition and strength/function in older adults with SO. MEDLINE, the Cochrane Central Register of Controlled Trials, CINAHL and SPORTDiscus were searched. Main inclusion criteria comprised sarcopenia as defined by the European Working Group on Sarcopenia in Older People (EWGSOP) and obesity defined as % body fat .40% (women) and .28% (men). Randomized controlled trials (RCTs), randomized controlled crossover trials and controlled clinical trials with older adults (mean age .65 years) following a nutritional regimen and/or an exercise training programwere considered. Out of 109 full text articles identified, only two RCTs (61 participants) met the inclusion criteria. One study was a nutritional intervention adding 15 g protein_Eday.1 (via cheese consumption) to the participants' habitual diet. The second study was a high-speed circuit resistance training intervention. Body composition did not change significantly in either of the studies. However,the exercise intervention improved significantly muscle strength and physical function. Although this review was limited by the small number of eligible studies, it provides evidence for the potential benefits of exercise and highlights the necessity for future research to develop effective interventions including dietary and exercise regimens to combat sarcopenic obesity.