The DASH (Dietary Approaches to Stop Hypertension) diet had been demonstrated to lower hs-cTnI, a biomarker of subclinical cardiac damage. However, the DASH diet’s effects on this biomarker had not been studied over time. The DASH-Sodium experiment was examined, a randomized controlled feeding study of healthy persons with a systolic blood pressure of 120 to 159 mm Hg and diastolic blood pressure of 80 to 95 mm Hg. The DASH diet or the average American diet was randomly given to participants (control). Participants in each trial arm were allocated three sodium levels in random order, which were varied every four weeks. Hs-cTnI was evaluated in serum at baseline, 4, 8, and 12 weeks of feeding. Throughout the study, energy intake was regulated to maintain body weight.

The final analysis comprised 411 individuals, with a mean age of 48 years, 56% of whom were women, and 56% were Black. At the start, the average systolic/diastolic blood pressure was 135/86 mm Hg. The control diet did not affect hs-cTnI compared to baseline at any time periods studied. The DASH diet, on the other hand, lowered hs-cTnI levels by 0.18 ng/l (95% CI: -0.32, -0.04) after 4 weeks, 0.14 ng/l (95% CI: -0.29, 0.00) after 8 weeks, and 0.33 ng/l (95% CI: -0.48, -0.18) after 12 weeks (Figure; P-trend = 0.025). At 4, 8, and 12 weeks, the percent-difference in mean change from baseline of hs-cTnI for DASH vs. control was -13.30% (95% CI: -25.34, 0.69), -10.47% (95% CI: -23.08, 4.21), and -17.78%(95% CI: -29.51, -4.09). The DASH diet lowered hs-cTnI within four weeks of feeding, with higher diet effects emerging after 12 weeks. The findings demonstrated that the DASH diet has both immediate and long-term impacts on subclinical heart damage.