Nutrition, Healthy
Conditions
Keywords
recommended intake of iodine, iodine balance study, thyroid diseases, elderly
Brief summary
Current Chinese dietary iodine reference intake (DRIs) standards lack direct data on recommended iodine intake (RNI) in the elderly. The elderly have a high prevalence of thyroid diseases. The risk threshold of iodine intake in the elderly is unknown. Identifying the appropriate iodine intake for the elderly to maintain optimal thyroid function to reduce the burden on medical resources is a public health issue requiring high attention. The iodine balance study is an important method for exploring physiological iodine requirements. Few iodine balance studies have been conducted in the elderly. This study aimed to conduct an iodine balance study and provide information on the appropriate iodine intake level for elderly people.
Detailed description
The investigators measured subjects' food and water intake throughout the day using weighing methods, and collected all urine and fecal samples. Food, drinking water, fecal and urine samples were taken to determine iodine concentrations. Each subject was required to participate in two phases of iodine balance studies. Each stage lasts 4 to 10 days. There was no intervention in the first half of the experiment, and there was an intervention of iodized salt/non-iodized salt consumption in the second half of the experiment. The appropriate level of iodine intake for the elderly was explored by fitting and analyzing the dose change relationship between iodine intake and iodine excretion.
Interventions
BEHAVIORALRestrict subjects' intake of iodine-containing foods
Replace subjects' iodized salt with non-iodized salt.
Sponsors
Tianjin Medical University General Hospital
Gansu Provincial Centre for Disease Control and Prevention
Wenxing Guo
Study design
Allocation
NA
Intervention model
SEQUENTIAL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
NONE
Intervention model description
When the first phase of the iodine balance study without intervention is completed. After an interval of 4 days, subjects who eat iodized salt will be included, the iodized salt will be replaced with non-iodized salt, and the second phase of the iodine balance experiment will begin.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
The target population of this study is elderly people over 60 years old. Adults living in the same household can also participate. Inclusion Criteria: 1. aged 18 and above; 2. at least 5 years of local residence.
Exclusion criteria
1. family genetic diseases； 2. special dietary habits； 3. taking iodine-containing drugs or supplements； 4. metabolic diseases; 5. thyroid diseases.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Iodine intake | Each phase of the iodine balance study lasts 4 to 10 days. | Daily iodine intake includes dietary iodine intake and drinking water iodine intake. |
| Iodine excretion | Each phase of the iodine balance study lasts 4 to 10 days. | Daily iodine excretion includes urinary iodine excretion and fecal iodine excretion. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| salivary iodine | 4 to 10 days | Every time the subject urinates, 2ml of saliva is collected. |
| thyroid function indexes | Within one week before the start of the experiment. | FT3、FT4、TSH、TPOAb、TGAb. Each subject was asked to collect venous blood twice (before the experiment and within one week after the intervention) to measure indicators of thyroid work. |
| fasting blood glucose | Within one week before the start of the experiment. | Subjects had their fasting blood glucose measured before and after the study. |
| blood pressure | Within one week before the start of the experiment. | Subjects had their blood pressure measured before and after the study. |
| thyroid volumn | Within one week before the start of the experiment. | Thyroid volume was measured using thyroid B-ultrasound. |
Countries
China
Contacts
Primary ContactWenxing Guo, doctor
Backup ContactZhangzhao Wang
Outcome results
None listed