Iodine nutrition improves in Latin America.
Iodine deficiency has been a public health problem in most Latin American countries. Massive programs of salt iodization have achieved great progress toward its elimination but no consistent monitoring has been applied. We used the ThyroMobil model to visit 163 sites in 13 countries and assess randomly selected schoolchildren of both genders 6-12 years of age. The median urinary iodine concentration (8208 samples) varied from 72 to 540 microg/L. One national median was below the recommended range of 100-200 microg/L; five were 100-200 microg/L, and seven were higher than 200 microg/L, including three greter than 300 microg/L. Urinary iodine concentration correlated with the iodine content of salt in all countries. Median values of thyroid volume were within the normal range for age in all countries, but the goiter prevalence varied markedly from 3.1% to 25.0% because of scatter. The median iodine content of salt from local markets (2734 samples) varied from 5.9 parts per million (ppm) to 78 ppm and was greater than 15 ppm in 83.1% of all samples. Only seven countries had higher than 15 ppm iodine in 80% of the samples, and only three had greater than 15 ppm in at least 90%. Iodized salt was available at retail level in all countries but its median iodine content was within the recommended range (20-40 ppm) in only five. This study, the first to apply a standardized assessment strategy to recent iodine nutrition in Latin America, documents a remarkable success in the elimination of iodine deficiency by iodized salt in all but 1 of the 13 countries. Some iodine excess occurs, but side effects have not been reported so far, and two countries have already decreased their legal levels of salt iodization and improved the quality control of iodized salt, in part because of our results. The present work should be followed by regular monitoring of iodine nutrition and thyroid function, especially in the countries presently exposed to iodine excess.
International Council for the Control of Iodine Deficiency Disorders, Instituto de Investigaciones de la Altura, Universidad Peruana Cayetano Heredia, Lima, Perú. epretell@terra.com.pe
Eduardo A
EA
Pretell
Francois
F
Delange
Ulrike
U
Hostalek
Sandro
S
Corigliano
Luis
L
Barreda
Ana María
AM
Higa
Noe
N
Altschuler
Derek
D
Barragán
José L
JL
Cevallos
Ofelia
O
Gonzales
Jorge A
JA
Jara
Geraldo
G
Medeiros-Neto
José A
JA
Montes
Santiago
S
Muzzo
Víctor M
VM
Pacheco
Luis
L
Cordero
D002648:Child; D019587:Dietary Supplements; D005260:Female; D006043:Goiter, Endemic / Q000178:diet therapy* / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D007455:Iodine / Q000008:administration & dosage* / Q000172:deficiency* / Q000652:urine; D007843:Latin America / Q000453:epidemiology; D008297:Male; D009749:Nutrition Surveys; D015995:Prevalence; D011634:Public Health; D012492:Salts / Q000008:administration & dosage; D013020:South America / Q000453:epidemiology
D012492:Salts; D007455:Iodine