High-fat meals followed by prolonged sitting bad for the heart

Prolonged, uninterrupted sitting right after eating a high-fat meal triggers elevations in cardiovascular disease markers, a recent study has found.

Thirteen young, healthy men were randomly assigned to eat a high-fat (61 g) or low-fat (10 g) meal, both of which were followed by 180 minutes of uninterrupted sitting. Meal allotments were then crossed over for the next experiment session. Cardiovascular disease markers assessed included carotid-femoral (cf) and femoral-ankle (fa) pulse wave velocity (PWV) and aortic-femoral stiffness gradient (af-SG), among others.

After eating a low-fat meal, participants showed significant change in cfPWV over the 180-minute sitting period (post-hoc mean difference [MD], 0.14 m·s^–1, 95 percent confidence interval [CI], 0.05–0.34; Cohen’s d=0.44). The high-fat meal, on the other hand, triggered a significant increase during prolonged siting (post-hoc MD, 0.59 m·s^–1, 95 percent CI, 0.28–0.89; Cohen’s d=1.12).

No such significant interactions and main effects were reported for faPWV. Meanwhile, af-SG showed no significant group effect, suggesting that diet fat content was unrelated to observed changes. However, there was a significant time effect, indicating that af-SG significantly worsened over time in both scenarios.

In terms of blood triglyceride concentration, participants saw significant increases with time after the high-fat meal (170 min: MD, 65 mg/dL, 95 percent CI, 11–120; Cohen’s d=1.52), as expected. There was no significant between-group difference in blood pressure.

“Collectively, these findings indicate that consuming a meal high in saturated fat prior to a period of uninterrupted prolonged sitting may cause additional stress on the cardiovascular system beyond sitting alone,” the researchers said.