Study design
inflammation, illness, A venous blood sample, fever
INFLAMMATION
This study follows a single-blinded, randomized, crossover design in which each subject consumes a sequence of 2 types of meals (biofortified and nonbiofortified potatoes). Each type of potato is labeled with a different stable iron isotope (A venous blood sample was collected on the first study day to determine the baseline iron isotopic composition as well as iron and inflammation status markers. Women began consuming the first randomly assigned potato meal labeled with 0.3 mg of the corresponding iron isotope: Study design for the potato study in Peru. Participants were randomly assigned to either the nonbiofortified or iron-biofortified test meals with iron isotopic administration (nonbiofortified test meal, Participants were blinded so they did not know the order in which the test meals were given. The first assigned test meal was consumed as breakfast for 10 consecutive days but was interrupted by a weekend break. On day 15, all participants switched over to the second test meal type, which they consumed for another 10 d. Each test meal consisted of 460 g of mashed potato served in 2 bowls of 230 g each. The test meals were weighed before and after consumption to calculate the intrinsic iron intake. The stable isotope solution was given in 50 mL water, which was drunk after the first 230-g portion had been consumed. In addition, each participant received 200 to 400 mL of mineral water.Meals were consumed under direct supervision by the study team after overnight fasting was confirmed. Participants were observed for 3 h after the test meals, and no food or drink was allowed other than mineral water (500 mL). Venous blood samples were collected by trained staff on days 15 and 40 to measure iron and markers of inflammation, and isotopic composition was measured in the days 1 and 40 samples. Subjects developing a fever or other symptoms of illness were discontinued from the study and advised to consult their medical doctor. The study was conducted under pandemic restrictions, respecting social distance, and all the measures adopted by the Peruvian government during the time of the study. The feeding trial had a duration of 20 wk (August to December 2021).