A food diary is a written record of all the foods and beverages a patient consumes over a period of time. This record helps patients track the types and quantities of foods they eat. Food diaries can also reveal the times of day a person eats and habits that may potentially cause health problems, such as excessive snacking or late-night binging.

People with digestive system conditions such as irritable bowel syndrome (IBS), chronic diarrhea, colitis, flatulence, diverticulosis and inflammatory bowel disease (IBD) may use food diaries to uncover clues about which foods or ingredients trigger symptoms.

Such clues can also be important in diagnosing and treating a food allergy (which involves an immune-system reaction) or food intolerance (which does not involve the immune system). However, numerous and often subtle factors influence whether or not a person suffers a reaction. For this reason, food diaries alone often cannot pinpoint the nature of a person’s condition.

Food diaries can also be used to track the amount of calories, vitamins, minerals and protein consumed by patients. These results can be compared to guidelines established by the National Research Council in its recommended dietary allowances (RDAs). Patients can thus keep track of whether they are ingesting the appropriate amount and type of nutrients to remain healthy and adjust their diet to lose weight, if necessary.