Naomi Kakoschke1, Ian T Zajac1, Jeannie Tay2, Natalie D Luscombe-Marsh1, Campbell H Thompson3, Manny Noakes1, Jonathan D Buckley4, Gary Wittert3, Grant D Brinkworth5,6. 1. Commonwealth Scientific and Industrial Research Organisation-Health and Biosecurity, Adelaide, SA, Australia. 2. A-Star Singapore-Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore. 3. Freemasons Foundation Centre for Men's Health, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia. 4. Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA, Australia. 5. Alliance for Research in Exercise, Nutrition and Activity (ARENA), University of South Australia, Adelaide, SA, Australia. grant.brinkworth@csiro.au. 6. Commonwealth Scientific and Industrial Research Organisation-Health and Biosecurity, Riverside Corporate Park, 11 Julius Avenue, North Ryde, NSW, 2113, Australia. grant.brinkworth@csiro.au.
Abstract
AIMS: Very low-carbohydrate (LC) diets are popular for type 2 diabetes (T2DM) management; however, long-term effects on psychological health remain largely unknown. This study reports the effects of a LC diet on mood and cognitive function after 2 years and explores the potential predictors of changes in psychological health. METHODS: 115 adults (57% males; age: 58.5 ± 7.1 years) with obesity and T2DM were randomized to consume an energy reduced (~ 500 to 1000 kcal/day deficit), LC diet [14% energy as carbohydrate, 28% protein, 58% fat (< 10% saturated fat)] or an isocaloric high unrefined carbohydrate, low-fat diet [HC: 53% carbohydrate, 17% protein, 30% fat (< 10% saturated fat)] for 2 years. Both diets were combined with aerobic/resistance exercise (1 h, 3 days/week). Mood/well-being [Beck Depression Inventory (BDI), Spielberger State Anxiety Inventory (SAI), Profile of Mood States (POMS)], diabetes-related quality of life [Diabetes-39 (D-39)] and distress [Problem Areas in Diabetes (PAID) Questionnaire], and cognitive function were assessed during and post-intervention. RESULTS: 61 (LC: 33, HC: 28) participants completed the study. Weight loss was 9.1% after 12 months and 6.7% after 2 years with no difference between diet groups. There were no differences between the groups for the changes in any psychological health outcome (smallest p ≥ 0.19 for all time x diet interactions). Overtime, improvements in BDI, POMS [Total Mood Disturbance (TMD); four subscales], PAID, and D-39 (three subscales) scores occurred (p ≤ 0.05, time). Stepwise regression analysis showed improvements in BDI, POMS (TMD; two subscales), D-39, SAI, andPAID scores were significantly (p < 0.05) correlated with reductions in body weight and glycated hemoglobin. CONCLUSION: In adults with obesity and T2DM, energy-restricted LC and HC diets produced comparable long-term improvements on a comprehensive range of psychological health outcomes. The findings suggest both diets can be used as a diabetes management strategy as part of a holistic lifestyle modification program without concern of negative effects on mental well-being or cognition. TRIAL REGISTRATION: ACTRN12612000369820, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=362168&isReview=true . Data described in the manuscript, code book, and analytic code will not be made available because approval has not been granted by participants.
RCT Entities:
AIMS: Very low-carbohydrate (LC) diets are popular for type 2 diabetes (T2DM) management; however, long-term effects on psychological health remain largely unknown. This study reports the effects of a LC diet on mood and cognitive function after 2 years and explores the potential predictors of changes in psychological health. METHODS: 115 adults (57% males; age: 58.5 ± 7.1 years) with obesity and T2DM were randomized to consume an energy reduced (~ 500 to 1000 kcal/day deficit), LC diet [14% energy as carbohydrate, 28% protein, 58% fat (< 10% saturated fat)] or an isocaloric high unrefined carbohydrate, low-fat diet [HC: 53% carbohydrate, 17% protein, 30% fat (< 10% saturated fat)] for 2 years. Both diets were combined with aerobic/resistance exercise (1 h, 3 days/week). Mood/well-being [Beck Depression Inventory (BDI), Spielberger State Anxiety Inventory (SAI), Profile of Mood States (POMS)], diabetes-related quality of life [Diabetes-39 (D-39)] and distress [Problem Areas in Diabetes (PAID) Questionnaire], and cognitive function were assessed during and post-intervention. RESULTS: 61 (LC: 33, HC: 28) participants completed the study. Weight loss was 9.1% after 12 months and 6.7% after 2 years with no difference between diet groups. There were no differences between the groups for the changes in any psychological health outcome (smallest p ≥ 0.19 for all time x diet interactions). Overtime, improvements in BDI, POMS [Total Mood Disturbance (TMD); four subscales], PAID, and D-39 (three subscales) scores occurred (p ≤ 0.05, time). Stepwise regression analysis showed improvements in BDI, POMS (TMD; two subscales), D-39, SAI, and PAID scores were significantly (p < 0.05) correlated with reductions in body weight and glycated hemoglobin. CONCLUSION: In adults with obesity and T2DM, energy-restricted LC and HC diets produced comparable long-term improvements on a comprehensive range of psychological health outcomes. The findings suggest both diets can be used as a diabetes management strategy as part of a holistic lifestyle modification program without concern of negative effects on mental well-being or cognition. TRIAL REGISTRATION: ACTRN12612000369820, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=362168&isReview=true . Data described in the manuscript, code book, and analytic code will not be made available because approval has not been granted by participants.
Entities:
Keywords:
Diabetes; Diet; Macronutrient composition; Psychological well-being; Weight loss
Authors: Jeannie Tay; Ian T Zajac; Campbell H Thompson; Natalie D Luscombe-Marsh; Vanessa Danthiir; Manny Noakes; Jonathan D Buckley; Gary A Wittert; Grant D Brinkworth Journal: Br J Nutr Date: 2016-11-23 Impact factor: 3.718
Authors: Jeannie Tay; Campbell H Thompson; Natalie D Luscombe-Marsh; Thomas P Wycherley; Manny Noakes; Jonathan D Buckley; Gary A Wittert; William S Yancy; Grant D Brinkworth Journal: Diabetes Obes Metab Date: 2017-12-20 Impact factor: 6.577
Authors: G D Brinkworth; N D Luscombe-Marsh; C H Thompson; M Noakes; J D Buckley; G Wittert; C J Wilson Journal: J Intern Med Date: 2016-03-23 Impact factor: 8.989
Authors: Emma Sainsbury; Nathalie V Kizirian; Stephanie R Partridge; Timothy Gill; Stephen Colagiuri; Alice A Gibson Journal: Diabetes Res Clin Pract Date: 2018-03-06 Impact factor: 5.602