There are several methods to measure dietary intake, each with its advantages and limitations:
24-hour dietary recall: Participants recall all foods and beverages consumed in the past 24 hours. It is quick but may not represent usual intake. Food frequency questionnaire (FFQ): Participants report the frequency of consumption of specific foods over a defined period. It is useful for assessing habitual intake but relies on memory and may be less precise. Dietary records: Participants record all foods and beverages consumed over several days. It provides detailed information but can be burdensome and may alter eating behavior. Biomarkers: Biological samples (e.g., blood, urine) measure nutrient levels, offering objective data but often at a higher cost.
