Monthly fasting-mimicking diet cycles may be feasible for patients with type 2 diabetes (T2D) in primary care. However, diet-related difficulties may have caused a high discontinuation rate, highlighting challenges associated with maintaining the dietary regimen.
Researchers evaluated the feasibility of periodic fasting-mimicking diet (FMD) cycles among 100 patients with T2D who were randomly assigned to monthly 5-day FMD cycles plus usual care (n = 51) or usual care alone (n = 49) for 1 year. Eligible participants were receiving metformin or no glycemic control medication. The mixed-methods evaluation combined quantitative data on program completion, reasons for discontinuation, serum ketone levels, and treatment satisfaction with qualitative findings from focus group discussions.
Among participants assigned to the FMD group, 61% completed the 1-year program, while 31% and 8% discontinued because of diet-related issues and other reasons, respectively.
Serum ketone levels were higher in the FMD group compared with the usual-care group. Treatment satisfaction did not differ between groups, providing additional information about the feasibility of following the dietary program.
Focus groups involving 20 participants identified several facilitators of adherence, including convenience, short dietary cycles, not feeling hungry, internal motivation, belief in beneficial effects, perceived health improvements, and social support.
Participants also reported barriers related to the taste, quantity, and frequency of the FMD. Environmental temptations and lack of social support were additional challenges to maintaining the dietary regimen.
The findings should be interpreted in light of the study's relatively small sample and restricted treatment population. Participants were receiving metformin or no medication for glycemic control, which may limit the applicability of the results to patients receiving other glucose-lowering therapies. The qualitative component involved 20 participants, and the 39% discontinuation rate demonstrated that the program was not sustainable for everyone. The study evaluated feasibility rather than establishing long-term clinical effectiveness.
"Adherence might be enhanced by addressing identified facilitators and barriers," wrote lead study author Marjolein P. Schoonakker, of the Department of Public Health and Primary Care at Leiden University Medical Center in The Netherlands, and colleagues.
The study authors declared no conflicts of interest.
Source: Clinical Nutrition Open Science