Diabetes Core Update – October 2025

Podcast: Diabetes Core Update
Release Date: October 3, 2025
Hosts: Dr. Neil Skolnik & Dr. John J. Russell
Special Guest: Dr. Rebecca Graves (segment one)

Overview

This episode provides a concise, insightful review of newly published research from major diabetes journals, with a focus on clinically relevant evidence that can inform practice for providers treating diabetes and related metabolic conditions. Topics explored include the impact of ultra-processed foods on women with gestational diabetes, mortality risk reduction from plant-based diets, novel pharmacotherapy in chronic kidney disease and type 2 diabetes, risk of phimosis with SGLT2 inhibitors, and ocular safety signals with GLP-1 receptor agonists.

Key Discussion Points & Insights

1. Ultra-Processed Foods, Diet Quality, and Type 2 Diabetes Risk in Gestational Diabetes Survivors

(Diabetes Care)
Featuring: Dr. Rebecca Graves ([00:03]–[10:07])

• Background:

  • Women with gestational diabetes (GDM) are at higher subsequent risk for type 2 diabetes.
  • Ultra-processed food (UPF) consumption is increasingly scrutinized for its metabolic impact.

• Study Design:

  • Nurses’ Health Study II cohort; n=4,207 women with history of GDM; ~30-year longitudinal follow-up.
  • Used NOVA classification for UPFs and Alternate Healthy Eating Index (AHEI) for diet quality.

• Findings:

  • Strong dose-response: Higher UPF intake linked with increased weight gain and higher T2D risk.
  • “Increased habitual consumption of ultra processed food led to diabetes, basically to type 2 diabetes. Even if that person has a higher healthy consumption score.” — Dr. Graves [04:47]
  • Weight gain difference relatively modest (1 kg more over 30 years for highest UPF quartile), but diabetes risk increase substantial: 20–25% elevation in highest vs. lowest UPF groups.

• Clinical Implications:

  • UPF intake should be a central component in dietary counseling for women after GDM.
  • Substitution effect: “The consumption of ultra processed foods often substitutes the consumption of healthy foods.” — Dr. Graves [07:59]
  • Additional concerns: UPF packaging (plastics/chemicals linked to endocrine disruption), non-nutritive food burden, impacts on gut microbiome.

• Memorable Quotes:

  • “UPF [ultra processed food] consumption is a critical factor in assessing diet quality for optimal cardiometabolic health.” — Dr. Graves [06:14]
  • “Most ultra processed foods are often non-nutritive, they often have zero nutritional contribution to our diets.” — Dr. Graves [08:49]

2. Plant-Based Diets and Mortality in Diabetes

(Diabetes Care)
Summary by hosts ([10:10]–[11:58])

• Study Overview:

  • UK Biobank cohort, >4,800 T2D patients, >11 years median follow-up.
  • Assessed “Plant Diet Index” (PDI), healthy PDI, and unhealthy PDI.

• Major Results:

  • Highest adherence to healthy PDI: 21% lower all-cause mortality; unhealthy PDI: 24% higher risk.
  • Effects even greater in patients with poor glycemic control, central adiposity, early-onset, or long-duration diabetes.

• Clinical Perspective:

  • “We’re looking at mortality, all cause mortality as the major endpoint and seeing a 20% difference over 11 years. That is...really big and important.” — Dr. Skolnik [11:58]
  • Plant-based healthy diets should be an aspirational goal in diabetes care, though dietary adherence remains challenging in today’s food environment.

3. Combination Therapy: Finerenone with Empagliflozin in T2D and CKD

(New England Journal of Medicine)
Summary by hosts ([11:58]–[15:49])

• Study Details:

  • Randomized trial; patients with T2D, CKD, albuminuria, on background renin-angiotensin system inhibition.
  • Compared finerenone, empagliflozin, and their combination (180-day outcome: UACR reduction).

• Outcomes:

  • Combination decreased urinary albumin-to-creatinine ratio by 29–32% more than either agent alone.
  • Adverse events (hypotension, AKI, hyperkalemia) were rare and comparable between groups.

• Practice Takeaway:

  • Early interventions in CKD3/CKD4 stages are pivotal to altering the course of kidney disease and its cardiac consequences.
  • “Protecting the kidneys is a cardiac event…has effects on the heart which everyone can see outcomes and mortality with that.” — Dr. Russell [15:49]

4. Phimosis Risk with SGLT2 Inhibitors vs. GLP-1 RA

(Diabetes Care)
Summary by hosts ([15:49]–[20:14])

• Study Recap:

  • Danish cohort, men starting SGLT2 inhibitors or GLP-1RAs (all metformin users).
  • SGLT2s: 32,000+ users; GLP-1: ~15,000. Median 4-year follow-up.

• Key Results:

  • SGLT2 inhibitors had higher risk: 1-year risk of phimosis 0.9% vs. 0.5%; 8-year risk ~4.8% vs. 3.6% (RR 1.36).
  • Penile cancer numerically higher (not significant) in SGLT2 group.

• Population Considerations:

  • Risk more pertinent in countries with lower circumcision prevalence (e.g., Denmark ~5–10% vs. US ~80%).

• Commentary:

  • “These are significant increases in risk and an absolute incidence of close to 5% over five years is real and important.” — Dr. Skolnik [20:14]

5. GLP-1 Receptor Agonists and Sight-Threatening Eye Complications in Type 2 Diabetes

(JAMA Network Open)
Summary by hosts ([20:14]–[26:25])

• Study Recap:

  • Retrospective cohort, >185,000 adults with T2D (US Trinex database, 2015–2022).
  • GLP-1 RA use associated with:
    • Slight increase in diabetic retinopathy diagnosis (HR 1.07).
    • In existing retinopathy cases, no increase in progression to proliferative retinopathy or macular edema, but reduction in vitreous hemorrhage (HR 0.70), neovascular glaucoma (HR 0.78), and blindness (HR 0.77).

• Expert Take:

  • “Science is not static. Science kind of evolves and we have to continue to look to things to make care better and make care safer.” — Dr. Russell [23:11]
  • The clinical significance of small, statistically marginal safety signals must be weighed against overall cardiovascular and glycemic benefits, especially in the context of broadening GLP-1 RA use (e.g., non-diabetic populations).

Notable Quotes & Memorable Moments

• “[Ultra processed food] consumption is a critical factor in assessing diet quality for optimal cardiometabolic health.” — Dr. Rebecca Graves [06:14]
• “Here we’re looking at mortality, all cause mortality as the major endpoint and seeing a 20% difference over 11 years. That is...really big and important.” — Dr. Neil Skolnik [11:58]
• “Protecting the kidneys is a cardiac event…has effects on the heart which everyone really can linear see the outcomes and mortality with that.” — Dr. John Russell [15:49]
• “Science is not static...we have to continue to look to things to make care better and make care safer.” — Dr. John Russell [23:11]

Timestamps for Major Segments

| Segment/Article | Timestamps | |---------------------------------------------------------------------------------------|--------------| | Ultra-Processed Foods in Gestational Diabetes (Graves interview) | 00:03–10:07 | | Plant-Based Diet & Mortality in T2D | 10:10–11:58 | | Finerenone + Empagliflozin in T2D & CKD | 11:58–15:49 | | Phimosis risk: SGLT2i vs. GLP-1s | 15:49–20:14 | | GLP-1 RAs and Eye Complications | 20:14–26:25 | | Rebranding Announcement & Closing | 26:25–27:31 |

Podcast Update

Announcement: Starting next month, the podcast will be rebranded as "Diabetes, Obesity and Cardiometabolic Update" (Doc Update) to reflect the expanded focus on the full spectrum of cardiometabolic health. Same format, broader scope.

For full articles and more resources, visit diabetesjournals.org.