Association between metabolic dysfunction-associated steatotic liver disease, vitamin D3, and diabetic gastric motility disorders in type 2 diabetes mellitus.

This letter comments on a study linking metabolic dysfunction-associated steatotic liver disease (MASLD), vitamin D3, and severe gastric autonomic neuropathy (diabetic gastric motility disorders) in type 2 diabetes mellitus (T2DM). We question the necessity of excluding patients with severe cataract (unable to complete fundus exams), as the focus on T2DM-MASLD correlation may render other T2DM complications less relevant. We emphasize vitamin D3's multifaceted relevance: It associates with T2DM (high-dose supplementation reduces onset risk), MASLD (serum levels predict risk), smooth muscle function, immunity, and T2DM-related fractures via advanced glycation end products. We propose correlating MASLD severity with vitamin D3 levels and diabetic gastric motility disorders in validation analyses (e.g., correlation, area under the curve) to refine factor analysis. Additionally, based on the authors' note of vitamin D3-tryptophan metabolism links, we call for deeper integration of metabolic pathways to clarify vitamin D3's role in smooth muscle electrophysiology, leveraging the team's prior research insights.