Maintaining a regular pancreatic fat content could reduce the risk of metabolic diseases like type 2 diabetes.
Obesity and physical inactivity are major risk factors for developing type 2 diabetes. Obesity leads to the accumulation of abnormal fat in multiple organs such as the heart and liver, and the accumulation of pancreatic fat may contribute to the development of beta-cell dysfunction.2 Dysfunction of these cells is already present before hyperglycemia develops; therefore, the pancreas is already functioning abnormally before a person receives a type 2 diabetes diagnosis. Exercise is known to improve whole-body insulin sensitivity, but its effects on pancreatic fat and beta-cell function are unknown. Physical activity has a vital role in type 2 diabetes prevention and management; maintaining a regular pancreatic fat content could reduce the risk of metabolic diseases.
A recently published parallel-group randomized controlled trial aimed to assess whether exercise training would have similar effects on the pancreas in healthy men and men with pre-diabetes or type 2 diabetes. This study by Heiskanen et al. also looked at whether different types of exercise would yield the same result in men and women. Included subjects were 40-55 years old because this is the typical range for a type 2 diabetes diagnosis. Individuals were randomized to either spring interval training (SIT) or moderate-intensity continuous training (MICT). The primary outcome was pancreatic fat content, determined by proton magnetic resonance spectroscopy (MRS). The secondary outcomes were pancreatic glucose and fatty acid uptake, studied by positron emission tomography (PET).
Results showed that exercise training decreased pancreatic fat similarly in healthy men (4.4% to 3.6%) and men with pre-diabetes or type 2 diabetes (8.7% to 6.7%), p = 0.036. Pancreatic fatty acid and glucose uptake were similar in both of these groups as well. When looking at SIT vs. MICT, results showed that both types of exercise reduced pancreatic fat, and these findings were similar between men and women. This study showed for the first time that exercise training, either continuous or interval, decreases pancreatic fat content regardless of baseline glucose tolerance. The exercise training protocol utilized in this study lasted only two weeks, but was able to show changes as substantial as 31% in men who had fatty pancreas to start. A significant limitation was the use of MRS to measure fat content, which cannot distinguish intracellular fat accumulation in beta cells.
An even more recent study by Chiang et al. specifically examined blood glucose response to a 12-week moderate-intensity exercise program in patients with type 2 diabetes. At each session, before-exercise blood glucose (BEBG) and post-exercise blood glucose (PEBG) were tested and used to calculate exercise-induced blood glucose response (EIGR). Analysis showed that BEBG, PEBG, and EIGR all significantly declined (β= -1.76, P< 0.001; β= -1.10, P< 0.001; β= -0.59, P< 0.001) over time as the exercise sessions increased. Results also showed that afternoon or evening exercise significantly predicted lower EIGR compared to morning exercise. Overall, this study was able to show that a 12-week moderate exercise program progressively reduces blood glucose levels. Improved metabolic control achieved through exercise interventions led to enhanced blood glucose levels.
Although the sample size of these studies was small, the findings are impactful. Reducing ectopic fat and reducing blood glucose levels in patients with type 2 diabetes will potentially lead to fewer pharmaceutical interventions and improved overall long-term health consequences associated with diabetes. Exercise stimulates metabolism, promotes glucose uptake, increases insulin sensitivity, and much more.1 Physical activity is consistently encouraged for patients with type 2 diabetes, but patients do not commonly follow this recommendation. However, the hard findings from previously discussed studies may assist providers and patients by providing a better understanding of the impactful changes exercise alone can make.
- A two-week exercise regimen in 40-55-year-old subjects showed a uniform reduction in pancreatic fat among healthy men and men with pre-diabetes or type 2 diabetes.
- Pre- and post-exercise blood glucose levels significantly declined throughout a 12-week moderate-intensity exercise program, and morning exercise is associated with the highest blood glucose level changes.
- Increased insulin sensitivity, decreased ectopic fat, and improvements in metabolism and blood glucose are all beneficial effects of exercise, especially for patients with type 2 diabetes.
1. Chiang, Shang-Lin et al. “Effects of a 12-week moderate-intensity exercise training on blood glucose response in patients with type 2 diabetes: A prospective longitudinal study.” Medicine vol. 98,36 (2019): e16860. doi:10.1097/MD.0000000000016860
2. Heiskanen, Marja A et al. “Exercise training decreases pancreatic fat content and improves beta-cell function regardless of baseline glucose tolerance: a randomized controlled trial.” Diabetologia vol. 61,8 (2018): 1817-1828. doi:10.1007/s00125-018-4627-x
Stephanie Anderson, PharmD Candidate 2021, Skaggs School of Pharmacy and Pharmaceutical Sciences