Contribution of fortified foods and dietary supplements to total nutrient intakes and their adequacy in Japanese adults.

Background: This study examined how fortified foods and dietary supplements contributed to total nutrient intakes and their adequacy in Japanese adults.

Methods: Nutrient intake was estimated from 4-day dietary records of 392 adults (20-69 years) in total intake considering intakes from fortified foods and dietary supplements and in base diets without considering their intake. Users were defined as participants who used at least one fortified foods and/or dietary supplements during the 4-day recording period. The proportion of participants whose intake was below the Estimated Average Requirements (EAR) or exceeded the Tolerable Upper Intake Level (UL) provided in the Dietary Reference Intakes for Japanese was calculated.

Results: In 122 identified users (31% of participants) of fortified foods and/or dietary supplements, the mean contributions of fortified foods and dietary supplements to total intake were < 4% and < 21%, respectively, for all 25 examined nutrients. Users were more likely to meet the EAR than non-users for six nutrients in the base diets and nine nutrients in the total intake. Among the users, the prevalence of participants below the EAR decreased by ≥ 10% in the total intake compared with the base diet for five nutrients. No nutrient intake from the base diet exceeded the UL in users and non-users; however, vitamin B₆ intake in 2% of users exceeded the UL of their total intake.

Conclusion: Although the users of fortified foods and/or dietary supplements had better nutrient intake than non-users in base diets, fortified foods and dietary supplements helped the Japanese users achieve adequate intakes of certain nutrients without a risk of excessive intake (except for vitamin B₆).