Pharmacokinetic (PK) Study of Phytochemicals in Whole Grains (WGs)- Corn

Days 0-7: Healthy volunteers were recruited and instructed to avoid consuming any whole-grain products beginning one week before the intervention and continuing throughout the study period.

Day 8 - Pharmacokinetic (PK) Visit 1: Participants consumed two servings of either whole-grain or refined-grain (46 g of raw grain per serving; 92 g total). Blood and urine samples were collected at multiple time points over 48 hours, and baseline fecal samples were collected the day before the intervention.

Day 15 - Pharmacokinetic (PK) Visit 2: After a 6-day washout period, participants crossed over to the alternate treatment. Blood and urine samples were again collected at multiple time points over 48 hours.

Inclusion criteria

• Adults aged 25-70 years
• Body mass index (BMI) between 18 and 30 kg/m²
• Able to read, speak, and understand English
• No known allergy or intolerance to the test foods
• Normal blood and urine biochemical parameters
• No antibiotic use within the past 6 months
• Willing and able to comply with all study procedures, including dietary restrictions throughout the study period
• No medical conditions or lifestyle factors that, in the opinion of the investigators, would interfere with the study objectives

Exclusion criteria

• Active disease, including gout, heart disease, peripheral vascular disease, kidney disease, liver disease, cancer, diabetes, gastrointestinal disorders, or endocrine disorders that may interfere with the study
• Current smoker or use of tobacco products
• Unwilling or unable to comply with the required dietary restrictions during the study period