Abstract
OBJECTIVES: Dietary recommendations to reduce blood pressure (BP) have been widely disseminated and residents who live on islands have unique dietary characteristics. Here, we identified associations between dietary intake and BP levels among island residents in China. DESIGN: Cross-sectional study. SETTING: The Changhai islands, which is an important island county in China. PARTICIPANTS: A total of 876 residents, 18-88 years old, of Changhai county. MEASUREMENTS: Dietary intake and BP measurements were assessed using standardized questionnaires and protocols, respectively. Dietary intake was compared across BP categories and linear regression analyses were performed between dietary intake and systolic blood pressure (SBP) and diastolic blood pressure (DBP). RESULTS: Participants previously diagnosed with hypertension consumed less salt than those with undiagnosed high BP (p < 0.01). After exclusion of participants previously diagnosed with hypertension, salt and meat consumption were positively and linearly associated with both SBP (p < 0.01 and < 0.001, respectively) and DBP (p = 0.03 and < 0.01, respectively), whereas consumption of marine products was inversely associated with SBP (p = 0.047). Mixed edible oil and edible oil consumption were associated with SBP (p < 0.01) and DBP (p = 0.021), respectively. In the multiple linear regression model, meat intake was positively associated with both SBP and DBP (β = 0.139, p < 0.001; β = 0.066, p = 0.047, respectively), whereas consumption of marine products was inversely associated with SBP (β = -0.102, p <0.001), while mixed edible oil was associated with SBP (β = 0.062, p = 0.03). CONCLUSION: Adherence to nutritional recommendations can be improved among hypertensive patients, even those aware of their conditions. In the general island population, eating habits regarding salt, meat, edible oil consumption, and use of mixed edible oil increased the risk of hypertension onset, whereas marine products were found to decrease this risk.