title: A low glycaemic load breakfast can attenuate cognitive impairments observed in middle aged obese females with impaired glucose tolerance.
abstract: OBJECTIVE
  There has been no systematic investigation of the individual and combined effects of impaired glucose tolerance (IGT) and obesity on cognitive function in the absence of ageing. The aims were to examine the effects of IGT and increased waist circumference on cognitive function in ostensibly healthy adults, and to investigate whether a low glycaemic load (GL) breakfast can attenuate cognitive impairments in these populations.
  
  
  RESULTS
  Sixty five females aged 30-50 years were classified into one of four groups following waist circumference (WC) measurements and an oral glucose tolerance test: NGT/low WC (n = 25), NGT/high WC (n = 22), IGT/low WC (n = 9), IGT/high WC (n = 9). Memory, psychomotor and executive functions were examined 30 and 120 min after consuming low GL, high GL and water breakfasts according to a randomised, crossover, counterbalanced design. IGT was associated with impairment of verbal and spatial memory, and psychomotor function relative to females with NGT, independent of waist circumference. Increased waist circumference was associated with impairment of verbal memory and executive function relative to females with low WC, independent of IGT. Consumption of the LGL breakfast attenuated verbal memory impairment in the IGT/high WC group relative to the HGL breakfast and no energy control.
  
  
  CONCLUSIONS
  Increased central adiposity and abnormalities in glucose tolerance preceding type 2 diabetes can have demonstrable negative effects on cognitive function, even in ostensibly healthy, middle-aged females. The potential for GL manipulations to modulate glycaemic response and cognitive function in type 2 diabetes and obesity merits further investigation.
authors.affiliation: Institute of Psychological Sciences, University of Leeds, Woodhouse Lane, Leeds LS29JT, UK; School of Psychology and Clinical Language Sciences, Earley Gate, Whiteknights, University of Reading, Reading, UK. Electronic address: d.j.lamport@reading.ac.uk.
authors.forename: D J
authors.initials: DJ
authors.lastname: Lamport
authors.affiliation: Institute of Psychological Sciences, University of Leeds, Woodhouse Lane, Leeds LS29JT, UK.
authors.forename: H K
authors.initials: HK
authors.lastname: Chadwick
authors.affiliation: Institute of Psychological Sciences, University of Leeds, Woodhouse Lane, Leeds LS29JT, UK.
authors.forename: L
authors.initials: L
authors.lastname: Dye
authors.affiliation: St James's Hospital Centre for Diabetes, St James's University Hospital, Leeds LS97TF, UK.
authors.forename: M W
authors.initials: MW
authors.lastname: Mansfield
authors.affiliation: Institute of Psychological Sciences, University of Leeds, Woodhouse Lane, Leeds LS29JT, UK.
authors.forename: C L
authors.initials: CL
authors.lastname: Lawton
mesh_terms: D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D015992:Body Mass Index; D062408:Breakfast; D003072:Cognition Disorders / Q000097:blood / Q000178:diet therapy* / Q000517:prevention & control; D018592:Cross-Over Studies; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy*; D005260:Female; D018149:Glucose Intolerance / Q000178:diet therapy*; D005951:Glucose Tolerance Test; D038321:Glycemic Index; D006801:Humans; D008875:Middle Aged; D056128:Obesity, Abdominal / Q000097:blood*; D017697:Premenopause; D055105:Waist Circumference
chemical_list: D001786:Blood Glucose
keywords: Cognition; Cognitive performance; Glycaemic index; Glycaemic load; Impaired glucose tolerance; Obesity; Type 2 diabetes; Waist circumference