Objective:

Evaluate the feasibility of monthly 5-day fasting-mimicking diet (FMD) cycles for people with type 2 diabetes (T2D) in primary care.

Approach:

• Design: One hundred participants were randomly assigned to monthly FMD cycles plus usual care (n=51) or usual care alone (n=49) for 1 year.
• Participants: Participants were receiving metformin or no glucose-lowering medication.
• Evaluation: A mixed-methods assessment examined program completion, reasons for discontinuation, serum ketones, treatment satisfaction, and focus-group feedback from 20 participants.

Key Findings:

• Among participants assigned to FMD, 61% completed the 1-year program; 31% discontinued because of diet-related issues and 8% for other reasons.
• Serum ketone levels were higher in the FMD group than in the usual-care group; treatment satisfaction did not differ between groups.
• Reported adherence facilitators included convenience, short cycles, not feeling hungry, motivation, belief in benefits, perceived health improvements, and social support.
• Reported barriers included the diet’s taste, quantity, and frequency, as well as environmental temptations and lack of social support.

Interpretation:

The study assessed feasibility, not long-term clinical effectiveness. The authors noted that addressing identified facilitators and barriers might enhance adherence.

Limitations:

• The sample was relatively small.
• Participants were limited to those taking metformin or no glucose-lowering medication, limiting applicability to people receiving other therapies.
• The qualitative findings came from 20 participants, and 39% of the FMD group discontinued the program.

Sources:

• Clinical Nutrition Open Science