Long-Term Adherence to a Mediterranean Diet 1-Year after Completion of the MedLey Study

Karen J Murphy; Kathryn A Dyer; Belinda Hyde; Courtney R Davis; Ella L Bracci; Richard J Woodman; Jonathan M Hodgson

doi:10.3390/nu14153098

Long-Term Adherence to a Mediterranean Diet 1-Year after Completion of the MedLey Study

Nutrients. 2022 Jul 28;14(15):3098. doi: 10.3390/nu14153098.

Authors

Karen J Murphy^{1

2}, Kathryn A Dyer^{2

3}, Belinda Hyde³, Courtney R Davis^{1

2}, Ella L Bracci^{1

2}, Richard J Woodman⁴, Jonathan M Hodgson^{5

6}

Affiliations

¹ Alliance for Research in Exercise, Nutrition and Activity, University of South Australia, GPO Box 2471, Adelaide, SA 5001, Australia.
² Clinical and Health Sciences, University of South Australia, GPO Box 2471, Adelaide, SA 5001, Australia.
³ Allied Health and Human Performance, University of South Australia, GPO Box 2471, Adelaide, SA 5001, Australia.
⁴ Flinders Centre for Epidemiology and Biostatistics, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia.
⁵ Nutrition and Health Innovation Research Institute, School of Medical and Health Sciences, Edith Cowan University, 35 Stirling Highway, Perth, WA 6000, Australia.
⁶ Medical School, University of Western Australia, 35 Stirling Highway, Perth, WA 6000, Australia.

Abstract

Mediterranean populations enjoy the health benefits of a Mediterranean diet (MedDiet), but is it feasible to implement such a pattern beyond the Mediterranean region? The MedLey trial, a 6-month MedDiet intervention vs habitual diet in older Australians, demonstrated that the participants could maintain high adherence to a MedDiet for 6 months. The MedDiet resulted in improved systolic blood pressure (BP), endothelial dilatation, oxidative stress, and plasma triglycerides in comparison with the habitual diet. We sought to determine if 12 months after finishing the MedLey study, the participants maintained their adherence to the MedDiet principles and whether the reduction in the cardiovascular disease (CVD) risk factors that were seen in the trial were sustained. Participants completed a food frequency questionnaire, and a 15-point MedDiet adherence score (MDAS; greater score = greater adherence) was calculated. Home BP was measured over 6 days, BMI was assessed, and fasting plasma triglycerides were measured. The data were analysed using intention-to-treat linear mixed effects models with a group × time interaction term, comparing data at baseline, 2, 4, and 18 months (12 months post-trial). At 18 months (12 months after finishing the MedLey study), the MedDiet group had a MDAS of 7.9 ± 0.3, compared to 9.6 ± 0.2 at 4 months (p < 0.0001), and 6.7 ± 0.2 (p < 0.0001), at baseline. The MDAS in the HabDiet group remained unchanged over the 18-month period (18 months 6.9 ± 0.3, 4 months 6.9 ± 0.2, baseline 6.7 ± 0.2). In the MedDiet group, the consumption of olive oil, legumes, fish, and vegetables remained higher (p < 0.01, compared with baseline) and discretionary food consumption remained lower (p = 0.02) at 18 months. These data show that some MedDiet principles could be adhered to for 12 months after finishing the MedLey trial. However, improvements in cardiometabolic health markers, including BP and plasma triglycerides, were not sustained. The results indicate that further dietary support for behaviour change may be beneficial to maintaining high adherence and metabolic benefits of the MedDiet.

Keywords: Australians; MedLey study; Mediterranean diet; dietary intervention trial.

Publication types

Clinical Trial

MeSH terms

Australia
Blood Pressure
Diet, Mediterranean*
Humans
Olive Oil
Triglycerides
Vegetables

Substances

Olive Oil
Triglycerides

Grants and funding

This research received no external funding.