Relationship between Frequency of Meals Comprising Staple Grain, Main, and Side Dishes and Nutritional Adequacy in Japanese Adults: A Cross-Sectional Study.

Meals comprising a staple grain, a main, and side dishes (SMS meals) promote good dietary intake, yet limited studies have examined their multifactorial relationship with dietary intake. We investigated how demographic characteristics, lifestyle, and dietary habits affect the relationship between SMS meal frequency and nutrient intake adequacy. This cross-sectional study analyzed survey data from 331 Japanese adults (208 men and 123 women) aged 30-69 years in February 2019. SMS meal frequency was evaluated according to respondents' answers to how many days a week they consumed ≥2 daily SMS meals. Dietary intake was evaluated using the brief self-administered diet history questionnaire. Differences in nutrient intake adequacy among groups according to SMS meal frequency were determined using multiple logistic regression. Less frequent SMS meals correlated with a lower intake of protein, water-soluble vitamins, and certain minerals, with more individuals falling below the estimated average requirement for nutrient intake. However, no relationship was found between SMS meal frequency and nutrient intake concerning tentative dietary goals for preventing lifestyle-related diseases. Our findings indicate that adopting SMS meals could achieve adequate intake of some nutrients and enhance overall diet quality among Japanese adults.

Evaluation of protein requirements using the indicator amino acid oxidation method: a scoping review.

BACKGROUND: The indicator amino acid oxidation (IAAO) method has been accepted as an approach to evaluate habitual protein requirements under free-living conditions. OBJECTIVES: This scoping review reports on literature that evaluated protein requirements in humans using the IAAO methods. METHODS: Three databases (PubMed/Medline, Web of Science, and ProQuest) were systematically searched to identify studies that evaluated protein requirements using the IAAO method published in English until 5 June, 2023. We evaluated the study quality using previously developed criteria. We extracted the characteristics of the study design and the results of protein requirements. Two reviewers conducted both reviews and quality assessments independently; any differences among them were resolved by consensus or agreement of all team members. RESULTS: We extracted 16 articles targeting children, young adults (including pregnant women, resistance training athletes, endurance-training athletes, and team sports), and older adults. In quality assessment, 14 studies were evaluated "strong," but the remaining 2 were "moderate." These studies were conducted in only 3 countries and did not include all sexes or life stages. The range of the estimated average protein requirements of each life stage was 1.30 g/kg body weight/d for children, 0.87 to 2.10 (0.87-0.93 for general young adults, 1.22-1.52 for pregnant women, 1.49-2.00 for resistance-trained athletes, 1.65-2.10 for endurance athletes, and 1.20-1.41 for team sports athletes) g/kg body weight/d for young adults, and 0.85 to 0.96 g/kg body weight/d for older adults. CONCLUSIONS: Protein requirements in 14 studies were higher than the current reference for each sex, life stage, and physical activity that are related to protein requirements. In the future, protein requirements of various populations including sex and life stage could be assessed using the IAAO methods worldwide.

Determination of Optimal Daily Magnesium Intake among Physically Active People: A Scoping Review.

Little is known about the optimal daily magnesium (Mg) intake for individuals with high levels of physical activity. The aim of this study was to clarify the optimal dietary Mg intake for people with high levels of physical activity in a scoping review. In this review, we searched MEDLINE and Japan Medical Abstracts Society for studies published up to May 31, 2020. We conducted two searches, one for studies using gold standard measurement methods such as the balance method and factorial calculation (Search 1), and the other for studies using estimation from daily food intake (Search 2). We also performed a meta-analysis of studies that compared the Mg intake among physically active people with the Mg intake among controls. After the primary and secondary screening, 31 studies were included in the final review. All of the included studies examined professional or recreational athletes. We found no studies that examined the optimal intake of Mg using gold standard measurement methods. The Mg intake among physically active individuals was below the recommended dietary allowance in most studies. In five studies that conducted meta-analyses, physically active individuals had significantly higher intakes of Mg than controls, although these levels were still below the recommended dietary allowance. The present review revealed that evidence regarding the optimal daily magnesium intake is currently scarce, and further studies are needed.

The frequency of cooking dinner at home and its association with nutrient intake adequacy among married young-to-middle-aged Japanese women: the POTATO Study.

Home cooking has been suggested as a key to healthy dietary intakes. However, little is known about the association between cooking behaviour and nutrient intake among young-to-middle-aged women. We aimed to investigate the association between home cooking frequency and nutrient intake adequacy among married Japanese women. Self-administered questionnaires were used to assess the weekly frequency of cooking dinner at home and habitual nutrient intake during the preceding month. We evaluated nutrient intake adequacy by comparing the self-reported intake with two indices of the dietary reference intakes for Japanese (2015): the estimated average requirement (EAR) of fourteen nutrients, and the 'tentative dietary goal for preventing lifestyle-related diseases' (DG) of seven nutrients. A total of 143 participants (25-44 years old) completed the questionnaires, with 32·9 % of participants reporting a weekly home cooking frequency of seven times/week. Women with a higher home cooking frequency (seven times/week) were more likely to have children (P = 0·001) than those with a lower home cooking frequency (0-6 times/week). Of the nutrients evaluated, there was no significant difference between the two groups in meeting EAR and DG. Our findings suggest that daily home cooking may not be necessary to achieve adequate nutrient intake, specifically among married, young-to-middle-aged Japanese women.

The presence of children in households was associated with dietary intake among Japanese married women: the POTATO study.

A growing body of evidence from Western countries shows that the presence of children in households is associated with the dietary intake of adults, but little is known about this relationship in non-Western countries with different food cultures. Our aim was to examine whether dietary intake was different with respect to the presence of young children in the home among Japanese married women. Subjects were Japanese married women (aged 23-44 years) living with children aged less than 5 years (n 73) and married women who did not have children (n 85). Data regarding habitual dietary intake were obtained using a validated, self-administered diet history questionnaire. A cross-sectional comparison between women with young children and women without children was conducted using ANCOVA adjusted for potential confounding factors. Women with young children had a significantly greater intake of protein, carbohydrates, Na, Zn and Cu than did women without children. Intake of cereals, pulses and sugar was significantly higher among mothers than among non-mothers. Intake of both alcoholic and non-alcoholic beverages was significantly higher among non-mothers than among mothers. Thus, the presence of young children at home might influence women's intake of macronutrients and some minerals, especially Na, and beverages among Japanese married women. Our findings suggest that effective dietary interventions among Japanese mothers with young children may differ from those of married women without children.

Cross-sectional observation of the relationship of depressive symptoms with lifestyles and parents' status among Japanese junior high school students.

OBJECTIVES: Students' depressive symptoms might be related to their own risk factors and to their parents' status. The objective of this cross-sectional study was to examine the relationship of depressive symptoms with lifestyle variables and parents' psychological and socio-demographic status among Japanese junior high school students. METHODS: Of 477 students and their parents, 409 (85.7 %) students and 314 (65.8 %) parents participated in the study. Students answered self-reported questionnaire on depressive symptoms, their heights and weights, subjective stress, body dissatisfaction, lifestyles including sleep duration and extracurricular physical activity in school and other physical activity outside the school, and nutritional intake. Parents responded to questionnaire on depressive symptoms and socio-demographic status. RESULTS: The prevalence of depressive symptoms was 24.9 %. Students with depressive symptoms were more likely to have stress. Students in shorter and longer sleep duration groups were more likely to have depressive symptoms. The students with depressive symptoms had smaller amount of energy intake than did those without depressive symptoms. Multiple logistic regression analysis revealed significant relationships between students' depressive symptoms and some independent variables. Sex, subjective stress, "almost-never"-categorized extracurricular physical activity in school and other physical activity outside the school, and having a parent with depressive symptoms were significantly associated with students' depressive symptoms. CONCLUSION: Reducing mental stress and taking care of lifestyles, especially, "almost-everyday"-categorized extracurricular physical activity in school and other physical activity outside the school, may have benefits for students' mental health, and having a parent with depressive symptoms may be associated with students' depressive symptoms.