Abstract
BACKGROUND: More than one-fifth of the world’s population consumes Chinese cuisines regularly, but no evidence-based healthy diets fitting the Chinese food culture are available for implementation. METHODS: A multicenter, patient- and outcome assessor-blind, randomized feeding trial was conducted among 265 participants with 130 to 159 mmHg baseline systolic blood pressure (SBP) for 4 major Chinese cuisines (Shangdong, Huaiyang, Cantonese, Szechuan). After a 7-day run-in period on a control diet matching the usual local diets, participants were randomized to continue with the control diet or the cuisine-based Chinese heart-healthy diet for another 28 days. The primary outcome was SBP, and secondary outcomes included diastolic blood pressure and food preference score. Linear regression models were used to estimate the intervention effects and adjustments for the center. The incremental cost per 1 mmHg reduction in SBP was also calculated. RESULTS: A total of 265 participants were randomized (135 on the Chinese heart-healthy diet and 130 on the control diet), with 52% women, mean age of 56.5±9.8 years, and mean SBP and diastolic blood pressure of 139.4±8.3 and 88.1±8.0 mmHg, respectively, at baseline. The change in SBP and diastolic blood pressure from baseline to the end of the study in the control group was −5.0 (95% CI, −6.5 to −3.5) mmHg and −2.8 (95% CI, −3.7 to −1.9) mmHg, respectively. The net difference of change between the 2 groups in SBP and diastolic blood pressure were −10.0 (95% CI, −12.1 to −7.9) mmHg and −3.8 (95% CI, −5.0 to −2.5) mmHg, respectively. The effect size did not differ among cuisines (P for interaction=0.173). The mean food preference score was 9.5 (with 10 the best preferred) at baseline, and the net change during intervention was 0.1 (95% CI, −0.1 to 0.2; P=0.558). The incremental cost-effectiveness ratio per 1 mmHg SBP reduction was CNY 0.4 (USD 0.06) per day. No difference in the number of adverse events was found between the 2 groups (P=0.259), and none of the adverse events was associated with the intervention. CONCLUSIONS: The Chinese heart-healthy diet is effective, palatable, and cost-effective in reducing blood pressure in Chinese adults with high blood pressure, with a clinically significant effect applicable across major Chinese cuisine cultures.
Generated Summary
This study presents a multicenter, patient- and outcome assessor-blinded, randomized feeding trial designed to evaluate the efficacy and cost-effectiveness of a Chinese heart-healthy (CHH) diet in lowering blood pressure among adults in China. The study involved 265 participants with baseline systolic blood pressure (SBP) between 130 and 159 mmHg. Participants were randomly assigned to either continue their usual diet (control group) or consume a CHH diet tailored to four major Chinese cuisines (Shangdong, Huaiyang, Cantonese, Szechuan) for 28 days. The primary outcome was SBP, with secondary outcomes including diastolic blood pressure (DBP) and food preference. Linear regression models were used to estimate intervention effects and adjustments for the center. The study also calculated the incremental cost per 1 mmHg reduction in SBP. The research aimed to determine the CHH diet’s palatability, affordability, and health efficacy across major Chinese cuisine cultures, addressing the need for evidence-based dietary strategies to combat high blood pressure in China.
Key Findings & Statistics
- Participants: A total of 265 participants were randomized (135 on the Chinese heart-healthy diet and 130 on the control diet), with 52% women, mean age of 56.5±9.8 years.
- Baseline Blood Pressure: Mean SBP was 139.4±8.3 mmHg and mean DBP was 88.1±8.0 mmHg at baseline.
- Changes in Blood Pressure (Control Group): The change in SBP in the control group was -5.0 (95% CI, -6.5 to -3.5) mmHg and DBP was -2.8 (95% CI, -3.7 to -1.9) mmHg.
- Changes in Blood Pressure (CHH Diet Group): The net difference of change in SBP was -10.0 (95% CI, -12.1 to -7.9) mmHg and DBP was -3.8 (95% CI, -5.0 to -2.5) mmHg, respectively.
- Effect Size: Effect size did not differ among cuisines (P for interaction = 0.173).
- Food Preference: The mean food preference score was 9.5 (with 10 being the best preferred) at baseline, and the net change during intervention was 0.1 (95% CI, -0.1 to 0.2; P=0.558).
- Cost-Effectiveness: The incremental cost-effectiveness ratio per 1 mmHg SBP reduction was CNY 0.4 (USD 0.06) per day.
- Adverse Events: No difference in the number of adverse events was found between the 2 groups (P=0.259), and none of the adverse events was associated with the intervention.
- Subgroup Analysis: Female participants experienced a greater reduction in SBP (-12.0 [95% CI, −15.0 to −9.0] mmHg) than men (-7.6 [95% CI, −10.4 to −4.7] mmHg), with a P for interaction of 0.037.
- Nutrient Intake Changes (CHH Diet): The CHH diet increased the percentage of energy intake from carbohydrates and protein, and decreased it for fat. Increased fiber, potassium, magnesium, and calcium, and decreased sodium intakes (all P values <0.05).
- Urinary Excretion Changes: The net change in estimated 24-hour urinary sodium and potassium excretion was -2194 mg (95% CI, -2870 to -1517) and 941 mg (95% CI, 363 to 1519), respectively, in line with the changes in dietary sodium and potassium intake.
- Weight Change: The mean change in weight from the baseline to the end of the intervention was −0.6 (±1.0) kg and 0.1 (±1.0) kg in the CHH diet and control diet groups, respectively (P<0.001).
Other Important Findings
- The CHH diet effectively reduced SBP and DBP.
- The study found that the intervention effect applied to all 4 major cuisines of Chinese culture.
- The food variety defined by the number of food items consumed by study participants was, on average, 4.7 (95% CI, 4.4 to 5.1) more in the CHH diet group than in the control diet group.
- The average cost for food materials was CNY 24 and CNY 21 per day for the CHH and control diets, respectively.
Limitations Noted in the Document
- The study did not reach the planned recruitment target due to the COVID-19 pandemic and associated quarantine policies.
- The study may not have sufficient power to detect the effect of cuisine type on the effect.
- The study collected spot urine only in the morning for feasibility consideration.
- The study could not separate the effect of reducing sodium intake from those caused by changes in diet by design.
- The study did not use whole food analysis to measure nutrients contents in the actual meals.
- The study did not achieve the targets of calcium in the CHH diet during the intervention.
Conclusion
The DECIDE-Diet trial demonstrated that the cuisine-based CHH diet effectively reduced SBP and DBP among Chinese adults with mild hypertension. The diet’s palatability was comparable to the usual local diet, and the cost was low. According to the systematic review and meta-analysis, if the effect achieved by the CHH diet, is sustainable, it would lead to a 20% reduction in major cardiovascular disease, 28% reduction in heart failure, and 13% reduction in all-cause death. The study provides a strong scientific basis for implementing the “healthy eating” campaign in China. The CHH diet is the first healthy diet developed according to the Chinese food culture. The findings supported the concept that “food is medicine” and highlighted the importance of healthy diets in controlling hypertension and related cardiovascular diseases. The study demonstrated that the blood pressure-lowering effect could be substantial and compatible with medications while palatable and affordable. Clinicians should recommend that their Chinese patients with high blood pressure adopt a healthy diet with low sodium and high potassium, fiber, vegetables, and fruits as the first-line treatment.