Potato consumption, by preparation method and meal quality, with blood pressure and body mass index: The INTERMAP study.

BACKGROUND AND AIMS: Previous studies have reported associations between higher potato intake and higher blood pressure (BP) and/or risk of hypertension and obesity. These studies rarely considered preparation methods of potatoes, overall dietary pattern or the nutrient quality of the meals. These factors may affect the association of potato intake with BP and body mass index (BMI). This study investigated potato consumption by amount, type of processing, overall dietary pattern, and nutrient quality of the meals in relation to BP and BMI. METHODS: Cross-sectional analyses were conducted among 2696 participants aged 40-59 y in the US and UK samples of the International Study of Macro- and Micro-Nutrients and Blood Pressure (INTERMAP). Nutrient quality of individual food items and the overall diet was assessed with the Nutrient-Rich Foods (NRF) index. RESULTS: No associations with BP or BMI were found for total potato intake nor for boiled, mashed, or baked potatoes or potato-based mixed dishes. In US women, higher intake of fried potato was associated with 2.29 mmHg (95% CI: 0.55, 3.83) higher systolic BP and with 1.14 mmHg (95% CI: 0.10, 2.17) higher diastolic BP, independent of BMI. Higher fried potato consumption was directly associated with a +0.86 kg/m2 difference in BMI (95% CI: 0.24, 1.58) in US women. These associations were not found in men. Higher intakes of fried potato meals with a lower nutritional quality (NRF index≤ 2) were positively associated with systolic (3.88 mmHg; 95% CI: 2.63, 5.53) and diastolic BP (1.62 mmHg; 95% CI: 0.48, 2.95) in US women. No associations with BP were observed for fried potato meals with a higher nutritional quality (NRF index> 2). CONCLUSIONS: Fried potato was directly related to BP and BMI in women, but non-fried potato was not. Poor-nutrient quality meals were associated with intake of fried potatoes and higher BP, suggesting that accompanied dietary choices are key mediators of these associations.