Iron intake and associated factors in general Japanese population: NIPPON DATA80, NIPPON DATA90 and national nutrition monitoring

Oral Health and Nutritional Intake in Community-Dwelling 90-Year-Old Japanese People: A Cross-Sectional Study

INTRODUCTION

This study aimed to determine the relationship between dentition, mastication, salivation and nutritional intake in 90-year-old Japanese people.

METHODS

This cross-sectional study included 84 participants (39 men and 45 women) aged 90 years. We used questionnaires to collect demographic information, smoking status, nutritional intake and higher-level functional capacity. Nutritional intake was assessed using the validated Brief-Type Self-Administered Diet History Questionnaire, and higher-level functional capacity was assessed using the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG-IC) questionnaire. Oral examinations, masticatory performance tests, stimulated salivary flow rate (SSF) tests, blood tests, blood pressure tests and body mass index (BMI) assessments were conducted. Univariable and multivariable linear regression analyses were performed.

RESULTS

Multivariable linear regression analyses adjusted for sex, education, TMIG-IC and BMI ≤20 kg/m² showed that participants with masticatory performance <173 mg/dL had lower intake of folic acid and vitamin A than those with masticatory performance ≥173 mg/dL. SSF was positively associated with intake of vitamin A. The number of teeth was positively associated with the intake of β-carotene. With smaller effect sizes, masticatory performance, SSF and number of teeth were also associated with the intake of various micronutrients and carbohydrates.

CONCLUSION

Lower masticatory performance, lower SSF and fewer teeth were associated with a lower intake of several micronutrients, such as vitamin A, β-carotene and folic acids, in Japanese individuals of advanced age. Oral health practitioners should pay careful attention to the nutritional intake of older people with poor mastication, dry mouth and severe tooth loss.

Dietary iron overload enhances Western diet induced hepatic inflammation and alters lipid metabolism in rats sharing similarity with human DIOS

Hepatic iron overload is often concurrent with nonalcoholic fatty liver disease (NAFLD). Dysmetabolic iron overload syndrome (DIOS) is characterized by an increase in the liver and body iron stores and metabolic syndrome components. Increasing evidences suggest an overlap between NAFLD with iron overload and DIOS; however, the mechanism how iron is involved in their pathogenesis remains unclear. Here we investigated the role of iron in the pathology of a rat model of NAFLD with iron overload. Rats fed a Western (high-fat and high-fructose) diet for 26 weeks represented hepatic steatosis with an increased body weight and dyslipidemia. Addition of dietary iron overload to the Western diet feeding further increased serum triglyceride and cholesterol, and enhanced hepatic inflammation; the affected liver had intense iron deposition in the sinusoidal macrophages/Kupffer cells, associated with nuclear translocation of NFκB and upregulation of Th1/M1-related cytokines. The present model would be useful to investigate the mechanism underlying the development and progression of NAFLD as well as DIOS, and to elucidate an important role of iron as one of the "multiple hits" factors.

Non-Heme Iron Absorption and Utilization from Typical Whole Chinese Diets in Young Chinese Urban Men Measured by a Double-Labeled Stable Isotope Technique

BACKGROUND

This study was to observe the non-heme iron absorption and biological utilization from typical whole Chinese diets in young Chinese healthy urban men, and to observe if the iron absorption and utilization could be affected by the staple food patterns of Southern and Northern China.

MATERIALS AND METHODS

Twenty-two young urban men aged 18-24 years were recruited and randomly assigned to two groups in which the staple food was rice and steamed buns, respectively. Each subject received 3 meals containing approximately 3.25 mg stable 57FeSO4 (the ratio of 57Fe content in breakfast, lunch and dinner was 1:2:2) daily for 2 consecutive days. In addition, approximately 2.4 mg 58FeSO4 was administered intravenously to each subject at 30-60 min after dinner each day. Blood samples were collected from each subject to measure the enrichment of the 57Fe and 58Fe. Fourteen days after the experimental diet, non-heme iron absorption was assessed by measuring 57Fe incorporation into red blood cells, and absorbed iron utilization was determined according to the red blood cell incorporation of intravenously infused 58Fe SO4.

RESULTS

Non-heme iron intake values overall, and in the rice and steamed buns groups were 12.8 ±2.1, 11.3±1.3 and 14.3±1.5 mg, respectively; the mean 57Fe absorption rates were 11±7%, 13±7%, and 8±4%, respectively; and the mean infused 58Fe utilization rates were 85±8%, 84±6%, and 85±10%, respectively. There was no significantly difference in the iron intakes, and 57Fe absorption and infused 58Fe utilization rates between rice and steamed buns groups (all P>0.05).

CONCLUSION

We present the non-heme iron absorption and utilization rates from typical whole Chinese diets among young Chinese healthy urban men, which was not affected by the representative staple food patterns of Southern and Northern China. This study will provide a basis for the setting of Chinese iron DRIs.

Meat intake frequency and anemia in Japanese children and adolescents

The consumption of meat products is considered to be a feasible solution to prevent anemia, which is a critical health problem. The present study assessed hematological parameters and the prevalence of anemia in Japanese children and adolescents, and examined the association with the frequency of meat intake. Data from the Shunan Children Health Cohort Study were analyzed. The participants included male and female residents, 3373 children (aged 10-11 years), and 3085 adolescents (aged 13-14 years). The frequency of meat intake was determined with a questionnaire, and blood samples were analyzed. Anemia was defined according to the criteria of the World Health Organization. The prevalence of anemia in children was 3.6% and 2.5% in girls and boys, respectively, and in adolescents, it was 4.5% in girls and 0.8% in boys. The frequency of meat intake did not show a positive association with the hematological indices or the prevalence of anemia. These results suggest that the promotion of meat consumption is not an effective strategy to decrease anemia, and that other approaches are necessary to prevent anemia in this population.