J-shaped association between dietary zinc intake and new-onset hypertension: a nationwide cohort study in China / 医学前沿

We aimed to investigate the relationship of dietary zinc intake with new-onset hypertension among Chinese adults. A total of 12,177 participants who were free of hypertension at baseline from the China Health and Nutrition Survey were included. Dietary intake was assessed by three consecutive 24-h dietary recalls combined with a household food inventory. Participants with systolic blood pressure ≽ 140 mmHg or diastolic blood pressure ≽ 90 mmHg or diagnosed by a physician or under antihypertensive treatment during the follow-up were defined as having new-onset hypertension. During a median follow-up duration of 6.1 years, 4269 participants developed new-onset hypertension. Overall, the association between dietary zinc intake and new-onset hypertension followed a J-shape (P for non-linearity < 0.001). The risk of new-onset hypertension significantly decreased with the increment of dietary zinc intake (per mg/day: hazard ratio (HR) 0.93; 95% confidence interval (CI) 0.88-0.98) in participants with zinc intake < 10.9 mg/day, and increased with the increment of zinc intake (per mg/day: HR 1.14; 95% CI 1.11-1.16) in participants with zinc intake ≽ 10.9 mg/day. In conclusion, there was a J-shaped association between dietary zinc intake and new-onset hypertension in general Chinese adults, with an inflection point at about 10.9 mg/day.

Dietary zinc intake is inversely associated with systolic blood pressure in young obese women

Zinc may participate in blood pressure regulation and in the pathogenesis of hypertension. The study examined the relationship between zinc status and blood pressure in obese Korean women. Forty obese women (body mass index (BMI) > or = 25 kg/m2) aged 19-28 years participated in this study. Zinc intake was estimated from one 24 hour recall and 2-day diet records. Serum and urinary zinc concentrations were determined by atomic absorbance spectrophotometry. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using an automatic sphygmometer. Metabolic variables, such as waist circumference, triglyceride, high density lipoprotein (HDL) cholesterol, fasting glucose, and fasting insulin, were also measured. Dietary zinc intake of obese women was averagely 7.5 mg/day. Serum zinc and urinary zinc concentrations were 13.4 micromol/L and 378.7 microg/day, respectively. Averages of SBP and DBP were 119 mmHg and 78 mmHg. Dietary zinc intake was negatively correlated with SBP after adjusting for energy intake (P < 0.05), but serum and urinary zinc concentrations were not found to be correlated with SBP or DBP. Multivariate linear regression analysis showed that dietary zinc intake was inversely associated with SBP in obese women after adjusting for body weight, energy intake and sodium intake (P = 0.0145). The results show that dietary zinc intake may be an independent risk factor of elevated SBP in obese Korean women.

The Zinc Nutriture and Effect of Zinc supplementation on the Elderly Living in Ulsan / 대한지역사회영양학회지

This study was intended to examine the zinc status and effect of zinc supplementation on the zinc nutritional status of the elderly living in the Ulsan area. The zinc intake of 207 subjects(male 97, female 110) was measured by a 24-hour dietary recall and food frequency method. Biochemical analysis were conducted from blood and urine samples to evaluate the changes of zinc nutriture with zinc supplementation. The average dietary zinc intake of subjects was 7.7+/-2.8 mg for male and 7.5+/-2.6 mg for female, which were 51.3% and 62.3% of Korean RDA respectively. The first source of zinc was cereal and grain(36%), and the second was eggs and milk group(27%). After 8 weeks of zinc supplementation, the serum zinc content was significantly increased(p<0.01), although the serum copper content was not significantly decrease. Serum HDL-cholesterol level was not significantly decreased with zinc supplementation. Serum alkaline phosphatase(ALP) activity and urinary zinc excretion were significantly increased(p<0.05). The urinary Zn/Cr was not significantly increased. It is suggested from the results that the daily zinc supplementation can be effective to improve zinc nutriture.

Zine Status of Adult Female in the Taegu Region as Assessed by Dietary Intake and Urinary Excretion / 대한지역사회영양학회지

This study was intended to examine the zinc status of free-living adult women living in the Taegu region. Zine intake of 102 female subjects was measured by food frequency method for 3 consecutive days. Urinary zine was assessed from urine samples collected fir twenty four hours. Average dietary zinc intake of adult female subjects using food record was 5.9+/-1.8 mg which was 49% of Korean RDA. When zine intake by frequency method was higher than by food record. Average urinary zine intake by frequency method was higher than that by food record. Thus, it appeared that zinc intake by frequency method was higher than that by food record. Average urinary zinc excretion of 102 adult female subjects was 0.28+/-0.16 mg, which belonged to marginal zinc deficiency range. Fifty nine of 102 subjects showed marginal zinc deficiency as assessed by urinary zinc excretion. If we compare the zinc status of adult female subjects by age group, zinc intake in the 50s was significantly higher than any other age groups. However, there were no significant differences in zinc status according to BMI groups and BMI groups. Significant correlations were found between zinc intake and energy, protein, carbohydrate and fat intake. Based on dietary zinc intake and urinary zinc, we concluded that zinc status of adult female living in the Taegu region is marginally deficient.