Iodine nutrition in Community-dwelling Older Persons from Norway

Abstract

Background: Older persons are vulnerable to malnutrition and inadequate micronutrient intake, including iodine deficiency.

Objectives: To assess urinary iodine concentration (UIC) and dietary iodine intake in a group of community-dwelling older persons receiving home care services in Oslo.

Method: One spot urine sample and two 24-hour dietary recalls were collected in 60 community-dwelling older persons (34 women and 26 men). UIC was analyzed by the Sandell-Kolthoff reaction and dietary iodine intake was calculated and compared to the provisional Average Requirement (AR). Multiple linear regression analyses were performed to find predictors for iodine intake.

Results: The median UIC (p25-p75) was 102 (64–168) μg/L and dietary iodine intake was 104 (69–173) μg/day. In total, 58% had iodine intakes below provisional AR. The main source of iodine was milk and dairy products, accounting for 42% of total iodine intake. In multiple linear regression analyses, iodine supplement use and oral supplement use were largely associated with iodine intake, (β, 95 % CI): 132 (76, 187) and 92 (23, 187), respectively. Increasing number of meals (β, 95 % CI): 48 (9, 86) and older age 2 (0, 4) was also associated with iodine intake.

Conclusions: Iodine status was found to be adequate at the group level, however, median iodine intake was below provisional AR. We found that the number of meals and total energy intake directly influenced iodine status. Most of the older persons consumed iodine-rich food items, thus the largest risk was not limited intake of iodine-rich food sources but limited energy intake.