title: Weight loss is associated with improvements in cognitive function among overweight and obese people: A systematic review and meta-analysis.
abstract: Whilst obesity is associated with a higher risk of cognitive impairment, the influence of weight loss on cognitive function in obese/overweight people is equivocal. We conducted a meta-analysis of randomized controlled trials (RCTs) and longitudinal studies evaluating the influence of voluntary weight loss on cognitive function in obese/overweight individuals. Articles were acquired from a systematic search of major databases from inception till 01/2016. A random effect meta-analysis of weight loss interventions (diet, physical activity, bariatric surgery) on different cognitive domains (memory, attention, executive functions, language and motor speed) was conducted. Twenty studies (13 longitudinal studies=551 participants; 7 RCTs=328 treated vs. 140 controls) were included. Weight loss was associated with a significant improvement in attention and memory in both longitudinal studies and RCTs, whereas executive function and language improved in longitudinal and RCT studies, respectively. In conclusion, intentional weight loss in obese/overweight people is associated with improvements in performance across various cognitive domains. Future adequately powered RCTs are required to confirm/refute these findings.
authors.affiliation: Department of Medicine, DIMED, University of Padova, Padova, Italy; Institute of Clinical Research and Education in Medicine (IREM), Padova, Italy. Electronic address: ilmannato@gmail.com.
authors.forename: Nicola
authors.initials: N
authors.lastname: Veronese
authors.affiliation: Department of Medicine, DIMED, University of Padova, Padova, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Facchini
authors.affiliation: Physiotherapy Department, South London and Maudsley NHS Foundation Trust, Denmark Hill, London SE5 8AZ, United Kingdom; Health Service and Population Research Department, Institute of Psychiatry, Psychology and Neuroscience, King's College London, De Crespigny Park, London, Box SE5 8AF, United Kingdom; Faculty of Health, Social Care and Education, Anglia Ruskin University, Chelmsford, United Kingdom.
authors.forename: Brendon
authors.initials: B
authors.lastname: Stubbs
authors.affiliation: Unit of Surgical Pathology, Santa Chiara Hospital, Trento, Italy; Department of Pathology and Diagnostics, Verona University and Hospital Trust, Verona, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Luchini
authors.affiliation: Institute of Clinical Research and Education in Medicine (IREM), Padova, Italy; Department of Neurosciences, University of Padova, Via Giustiniani, 5, 35128 Padova, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Solmi
authors.affiliation: Department of Medicine, DIMED, University of Padova, Padova, Italy; Aging Section, Institute of Neurosciences, Italian Research Council, Padova, Italy.
authors.forename: Enzo
authors.initials: E
authors.lastname: Manzato
authors.affiliation: Department of Medicine, DIMED, University of Padova, Padova, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Sergi
authors.affiliation: Aging Section, Institute of Neurosciences, Italian Research Council, Padova, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Maggi
authors.affiliation: MRC Unit for Lifelong Health and Ageing, London, United Kingdom.
authors.forename: Theodore
authors.initials: T
authors.lastname: Cosco
authors.affiliation: Division of Geriatrics and Nutritional Sciences and Center for Human Nutrition, Washington University School of Medicine, St. Louis, MO, USA; Department of Clinical and Experimental Sciences, Brescia University, Brescia, Italy; CEINGE Biotecnologie Avanzate, Napoli, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Fontana
mesh_terms: D003071:Cognition; D015444:Exercise; D006801:Humans; D009765:Obesity; D050177:Overweight; D015431:Weight Loss
keywords: Attention; Cognition; Memory; Meta-analysis; Nutrition; Obesity; Physical activity; Weight loss