Dietary phytochemical index is inversely associated with the occurrence of hypertension in adults: a 3-year follow-up (the Tehran Lipid and Glucose Study).

BACKGROUND/OBJECTIVE: The epidemiological association of phytochemical-rich foods with the risk of hypertension is unclear. This study aimed to determine the association of dietary phytochemical index (PI) with the occurrence of hypertension (HTN) after 3 years of follow-up in Tehranian adults. SUBJECTS/METHODS: This prospective study was conducted on 1546 nonhypertensive subjects, aged 20-70 years. Dietary intake was collected by validated semiquantitative food frequency questionnaire (FFQ). Dietary PI was calculated as (dietary energy derived from phytochemical-rich foods (kcal)/total daily energy intake (kcal)) × 100. Blood pressure was measured at baseline and after 3 years of follow-up and HTN was defined by Joint National Committee on prevention, detection, evaluation and treatment of high blood pressure criteria. The odds of HTN after 3 years in each quartile category of dietary PI were estimated by logistic regression model and adjusted for potential variables. RESULTS: The mean age of participants was 38.0±12.0 years and 43% were male. The mean dietary PI was 29.1±11.8. After 3 years of follow-up, 265 (17.1%) new cases of HTN were identified. No significant changes were observed in the systolic and diastolic blood pressure across quartile categories of dietary PI. After adjustment for confounders, the odds (95% confidence interval) of HTN across quartiles of dietary PI were 1.00, 0.97 (0.62-1.38), 0.69 (0.45-1.07) and 0.52 (0.32-0.84) (P for trend=0.004). CONCLUSIONS: Consumption of phytochemical-rich foods may prevent the development of HTN. Further investigations are, however, recommended.

Efficacy of flour fortification with folic acid in women of childbearing age in Iran.

BACKGROUND: Flour fortification with folic acid is one of the main strategies for improving folate status in women of childbearing age. No interventional trial on the efficacy of folic acid fortification has been conducted so far in Iran. OBJECTIVES: To study the effects of flour fortification with folic acid on any reduction in neural tube defects (NTDs) and folate status of women of childbearing age. METHODS: In a longitudinal hospital-based study, 13,361 postpartum women were studied after admission for childbirth before and after fortification. In addition, two cross-sectional surveys were conducted before (2006) and after flour fortification (2008). The cluster sampling method was used and 580 women, 15-49 years old, were studied as a representative sample of Golestan province in the north of Iran. Fasting blood samples were collected to measure serum vitamin B(12), folate and plasma homocysteine. Sociodemographic data, health characteristics and dietary intake were determined. RESULTS: The mean daily intakes of folate from natural food before and after flour fortification were 198.3 and 200.8 µg/day, respectively. The total folate intake increased significantly from 198.3 to 413.7 µg/day after fortification (p < 0.001). Folate intake increased by an average of 226 µg/day from fortified bread. The mean serum folate level increased from 13.6 to 18.1 nmol/l; folate deficiency decreased from 14.3 to 2.3% (p < 0.001). The incidence rate of NTDs declined by 31% (p < 0.01) in the post-fortification period (2.19 per 1,000 births; December 2007 to December 2008) compared to the pre-fortification period (3.16 per 1,000 births; September 2006 to July 2007). CONCLUSIONS: Implementation of mandatory flour fortification with folic acid can lead to a significant increase in serum folate and a significant decrease in NTDs.