Establishing heme iron values for the Canadian Nutrient File (CNF)

Objectives Heme iron, primarily from the hemoglobin and myoglobin of meat, poultry and fish (MFP) is better absorbed than non‐heme iron. Monsen et al. (1978) assumed that the proportion of heme iron contained in various meats averages 40%, while the remaining 60% is found in the less bioavailable non‐heme form. More recent evidence suggests that this ratio may vary depending on the type and cut of MFP. Currently, the CNF lists only total iron values. The objective of our research was to match heme iron values from the literature to foods within the CNF. Methods An extensive literature search was conducted to identify the heme content of different souces of MFP. Values from the literature were then matched to CNF foods with consideration of cuts and similarities to North American cooking methods. In order to match heme values from the literature to MFP foods, average values were often generated across cuts and cooking methods eg. ground chicken was an average of white and dark meat. Results and Discussion A broad range of heme values were observed across MFP types. The following heme values were attributed: 33–70% for beef cuts, 21–40% for fish, 27–66% for pork cuts, 26–37% for poultry, and 40–63% for veal. When no literature value for heme iron was found eg., game meats, and many types of fish, a value of 40% was used as a default. The heme content of beef, veal and some pork cuts are higher than 40%, while poultry and fish might have lower heme iron contents. Conclusion Incorporating heme iron values into the CNF that are reflective of various MFP provides useful data for assessing iron bioavailability from foods/diets and for developing future nutritional policies targeted at reducing iron deficiency.