Study: Prediabetes May Cause Persistent Fat Tissue Changes That Limit Weight Loss Benefits

New research suggests that prediabetes could be linked to lasting alterations in fat tissue that are not fully reversed by bariatric surgery and weight loss, potentially contributing to weight regain.

The findings were presented at the European Congress on Obesity in Istanbul (May 12-15) and examined changes in adipose tissue in women with severe obesity.

Study Design and Participants

The research involved 78 women with severe obesity (BMI 39-49 kg/m²) from the Hospital Clinic de Barcelona, Spain. Participants were divided into two groups for comparison:

• 43 women with normal glucose tolerance.
• 35 women with prediabetes.

Gene expression in subcutaneous fat tissue was analyzed at the time of bariatric surgery and again one year after surgery in a subgroup of 11 women from each group. Weight changes were tracked for up to three years.

Key Findings

Before Surgery

Before surgery, women with prediabetes had higher glucose and insulin responses, a higher prevalence of fatty liver (88% vs 57%), and less favorable lipid profiles compared to women with normal glucose tolerance.

One Year After Surgery

One year post-surgery, glycemic and metabolic parameters improved significantly in both groups. Short-term weight loss was similar between the groups (32.3% in the prediabetes group vs. 35.5% in the control group).

"Despite clinical improvement, gene activity in fat tissue remained distinct between groups one year post-surgery."

Crucially, the study found that women with prediabetes showed less active genes involved in lipid metabolism, including key genes like SREBF1 and FADS2. In contrast, women with normal glucose tolerance showed activation of genes involved in lipid metabolism and cholesterol handling.

Long-Term Weight Trajectory

Between years one and three after surgery, a notable difference in weight regain emerged:

• Women with prediabetes regained 5-6 kg on average.
• Women with normal glucose tolerance regained 1-2 kg on average.

Researcher Statements

"Our findings suggest that prediabetes is associated with persistent changes in fat tissue that may limit its ability to fully adapt after weight loss." – Camila Milad, study author.

"Our study shows that prediabetes is associated with persistent changes in fat tissue that are not fully reversed by bariatric surgery." – Dr. Ana de Hollanda, lead author.

Dr. de Hollanda added, "These alterations in lipid metabolism may reduce the ability of adipose tissue to adapt after weight loss, potentially contributing to weight regain over time."

Study Limitations

The authors noted several important limitations to their research:

• The observational study design does not establish causal relationships.
• The study included only women, predominantly of European origin.
• Behavioral factors like diet may also contribute to weight outcomes.
• Larger and more diverse studies are needed to confirm the results.