Characterisation of breakfast, lunch, dinner and snacks in the Japanese context: an exploratory cross-sectional analysis

Effect of breakfast protein intake on muscle mass and strength in adults: a scoping review

BACKGROUND

The distribution of protein intake throughout the day is frequently skewed, with breakfast having the lowest protein intake across all age groups. There is no review that addresses the association between breakfast protein intake and muscle mass and strength.

OBJECTIVE

This scoping review aims to summarize the literature on the relationship between protein intake during breakfast and muscle mass and strength in adults.

METHODS

This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. Two independent reviewers screened and appraised the articles identified from 3 electronic databases (Medline, Web of Science, and Scopus) that focused on protein intake per meal and its impact on muscle-related outcomes.

RESULTS

A total of 14 763 articles were retrieved from 3 databases, and after the screening process, 15 articles were included for analysis. Approximately 58.8% of findings from 11 studies examining the association between high protein intake during breakfast and muscle mass indicated an increase in muscle mass among participants. Half of 6 studies (50.0%) exploring the relationship between high protein intake at breakfast and muscle strength demonstrated an increase in muscle strength. Consuming high amounts of protein at breakfast or more protein in the morning than in the evening was associated with an increase in the skeletal muscle index and lean body mass.

CONCLUSION

Protein consumption at breakfast revealed potential benefits in increasing muscle mass across 5 studies involving an elderly population and 2 studies encompassing middle-aged women and young men in our review. However, the relationship between protein intake at breakfast and muscle strength remains unclear. Further high-quality randomized controlled trials are required to examine whether adults can preserve skeletal muscle health outcomes by consuming higher amounts of protein at breakfast.

Relative validity of three diet quality scores derived from the Brief-type Self-administered Diet History Questionnaire and Meal-based Diet History Questionnaire in Japanese adults

No study has validated questionnaires for assessing easily calculable diet quality scores in Japan. The Brief-type self-administered Diet History Questionnaire (BDHQ) is widely used to assess dietary intake in Japan, while the Meal-based Diet History Questionnaire (MDHQ) assesses dietary intake for each meal (breakfast, lunch, dinner and snacks) and overall dietary intake. This study examined the relative validity of the BDHQ and MDHQ for assessing three diet quality scores in Japanese adults. A total of 111 women and 111 men aged 30-76 years completed the web MDHQ and BDHQ, followed by 4-non-consective-day weighed dietary records. The diet quality scores examined included the Diet Quality Score for Japanese (DQSJ), Dietary Approaches to Stop Hypertension (DASH) score and Alternate Mediterranean Diet (AMED) score. The means of the three scores for overall diet from the BDHQ were not significantly different from those from the dietary records in both sexes, whereas those from the MDHQ were higher than those from the dietary records, except for the DASH and AMED in women. Pearson's correlation coefficients between both questionnaires and dietary records were 0·57-0·63 for DQSJ, 0·49-0·57 for DASH and 0·31-0·49 for AMED across both sexes and both questionnaires. For each meal, Pearson's correlation coefficients between the MDHQ and dietary records ranged from 0·01 (DASH for snacks in women) to 0·55 (DQSJ for breakfast in men), with a median of 0·35. This study showed that the ability of the BDHQ and MDHQ to rank individuals was good for DQSJ and DASH and acceptable for AMED.

Association between meal context and meal quality: an ecological momentary assessment in Japanese adults

PURPOSE

The purpose was to assess the relationship between the quality of meals and its context.

METHODS

We conducted a cross-sectional study of 222 Japanese adults aged 30-76 years in 2021. The following information was obtained from the 4-d weighed dietary records: the recording day (working or not), meal type (breakfast, lunch, or dinner), eating companions (alone or with someone), eating location (at home or away from home), and screen-based activity (yes or no). The nutritional quality of each meal was evaluated using the Healthy Eating Index 2020 (HEI-2020).

RESULTS

The analysis included 1,295 meals for males and 1,317 for females. The mean HEI-2020 ranged from 43.0 (lunch) to 51.9 (dinner) in males and from 45.7 (breakfast) to 52.0 (dinner) in females. Multilevel linear regression showed that, in males, lunch had a significantly lower HEI-2020 score compared to breakfast (β = -1.81, 95% confidence interval [CI]: -3.42, - 0.20), while dinner had a significantly higher HEI-2020 score (β = 6.77, 95% CI: 5.34, 8.20). Eating with someone was significantly associated with a higher HEI-2020 score (β = 2.22, 95% CI: 0.76, 3.67). Among females, dinner had a higher HEI-2020 score than breakfast (β = 5.21, 95% CI: 3.72, 6.70). Eating away from home was associated with higher HEI-2020 scores (β = 2.14, 95% CI: 0.04, 4.24).

CONCLUSION

Meal type, location, and eating companions were associated with meal quality in this population, with differences between males and females. Incorporating these factors in nutrition education and interventions can enhance diet quality.

Self-perceived food literacy in relation to the quality of overall diet and main meals: A cross-sectional study in Japanese adults

This cross-sectional study aimed to assess the relationship between self-perceived food literacy (SPFL) and quality of overall diet and main meals in Japanese adults. In total, 5998 adults aged 20-79 years were included in this analysis. The SPFL was assessed using the Japanese version of the 29-item Dutch SPFL scale (score range 1-5). Using validated dietary information, the Healthy Eating Index-2015 (HEI-2015) was calculated (score range 0-100). The mean SPFL was 3.18; the internal consistency of the overall scale was considered good (Cronbach's alpha: 0.80). The mean HEI-2015 for overall diet was 50.4. The SPFL was significantly and positively associated with the HEI-2015. Using multiple linear regression, one point increase of SPFL corresponded to an increase in HEI-2015 by a point of 4.8 for overall diet, 6.2 for breakfast, 4.6 for lunch, and 3.6 for dinner (all P < 0.0001). Six of the eight domains of SPFL (i.e., food preparation skills, resilience and resistance, healthy snack styles, examining food labels, healthy budgeting, and healthy food stockpiling) were significantly associated with the HEI-2015 for overall diet. When the HEI-2015 for each meal was examined, the domains showing significant associations with all three meals included food preparation skills, healthy snack styles, and healthy budgeting. The healthy food stockpiling was associated with the HEI-2015 for breakfast and lunch, but not dinner. The social and conscious eating and daily food planning were associated with the breakfast HEI-2015 only, with the resilience and resistance associated with the dinner HEI-2015 only. In conclusion, the SPFL was cross-sectionally associated with the quality of overall diet and main meals in Japanese adults. Further observation and intervention studies are needed to confirm the associations observed here.

The Nutritional Characteristics of Usual Lunches Consumed Among Japanese Workers: Comparison Between Different Lunch-Type Groups

OBJECTIVE

This study investigated whether the nutritional characteristics of lunches consumed by Japanese workers differ by where the meal is usually prepared or eaten.

METHODS

This cross-sectional study included 620 employees (aged 20 to 75 years) from eight business offices in Tokyo, Japan. Dietary data were collected using the validated Meal-based Diet History Questionnaire. The Healthy Eating Index 2015 and dietary intakes from lunch were compared between workers classified by usual lunch type: homemade (n = 190), staff canteen (n = 77), restaurant (n = 109), and takeaway (n = 244).

RESULTS

Healthy Eating Index 2015 for lunch was highest in the staff canteen group, followed by the homemade group. The staff canteen group had higher intakes of total vegetables, potatoes, fish, and several vitamins from lunch than the restaurant or takeaway groups.

CONCLUSIONS

Homemade and canteen lunches are relatively healthy options for lunch for Japanese workers.

Associations of food choice values and food literacy with overall diet quality: a nationwide cross-sectional study in Japanese adults

To date, a limited number of studies have examined aspects of food choice values and food literacy in relation to some aspects of dietary behaviours. The aim of this cross-sectional study was to comprehensively examine the associations of food choice values and food literacy with diet quality. In total, 2231 Japanese adults aged 19-80 years completed questionnaires asking about food choice values (accessibility, convenience, health/weight control, tradition, sensory appeal, organic, comfort and safety) and food literacy characterised by nutrition knowledge, cooking skills, food skills and eating behaviours (hunger, food responsiveness, emotional overeating, enjoyment of food, satiety responsiveness, emotional undereating, food fussiness and slowness in eating). As a measure of diet quality, the Healthy Eating Index-2015 (HEI-2015) was calculated using a brief-type diet history questionnaire (BDHQ) or a food combination questionnaire (FCQ). In males, after adjustment for potential confounding factors (including age, BMI and the ratio of reported energy intake to estimated energy requirement), the HEI-2015 derived from BDHQ and that derived from FCQ were associated significantly (P ≤ 0·02) and positively with the food choice values of organic and inversely with food fussiness. In females, the HEI-2015 showed positive associations with the food choice values of health/weight control, nutrition knowledge and cooking skills and an inverse association with food fussiness, irrespective of the dietary assessment questionnaire (P ≤ 0·03). In conclusion, this study suggests that several aspects of food choice values and food literacy were associated with diet quality, and the aspects related differed between males and females.

Meat or meatless meals at lunch and dinner – exploring the associated factors and transition between meals

This study aimed to explore the factors associated with the consumption of meat vs. meatless meals and to assess the applicability of a multi-state model to describe transitions between lunch and dinner. Fifteen thousand four hundred and eight main meals (lunch and dinner) from a sample of adults (18-84 years, n = 3852) from the Portuguese Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016) were categorised as meat, fish, ovolactovegetarian or snack. Adjusted generalised-mixed-effects models were used to explore the associations and a time-homogeneous Markov-multi-state model was applied to study the transitions. Women, older and higher educated individuals presented higher odds of consuming meatless meals and lower hazard of transitioning to meat in the following main meal. Strategies for replacing meat with more sustainable foods should be specific towards different population groups. Studying transitions across main meals, using multi-state models, can support the development of feasible, realistic and group-specific strategies to replace meat and promote dietary variety.

Food Categories for Breakfast and Mental Health among Children in Japan: Results from the A-CHILD Study

There is limited evidence that what children eat for breakfast contributes to their mental health. This study aimed to examine the associations between food categories for breakfast and mental health among children in Japan. A proportion of participants aged 9-10 years in the Adachi Child Health Impact of Living Difficulty (A-CHILD) study in Japan who consumed breakfast daily were included (n = 281). Foods eaten for breakfast were reported by the children each morning for 7 consecutive days, and defined according to the food categories in the Japanese Food Guide Spinning Top. Child mental health was assessed by caregivers using the Strength and Difficulties Questionnaire. The mean intake frequencies per week were six times for grain dishes, two times for milk products, and one time for fruits. Linear regression analysis revealed an inverse association between the frequent intake of grain dishes, whether rice or bread, and problem behaviors after adjustment for potential confounders. However, confectionaries, which mainly consisted of sweet breads or pastries, were not associated with problem behaviors. The intake of non-sweet grain dishes at breakfast may be effective for preventing behavioral problems in children.

Chrononutrition is associated with melatonin and cortisol rhythm during pregnancy: Findings from MY-CARE cohort study

Chrononutrition has been suggested to have an entrainment effect on circadian rhythm which is crucial for metabolic health. Investigating how chrononutrition affects maternal circadian rhythm can shed light on its role during pregnancy. This study aims to determine chrononutrition characteristics of healthy primigravida during pregnancy and its association with melatonin and cortisol rhythm across gestation. A total of 70 healthy primigravidas were recruited from ten randomly selected government maternal and child clinics in Kuala Lumpur, Malaysia. During the second and third trimesters, chrononutrition characteristics including meal timing, frequency, eating window, breakfast skipping, and late-night eating were determined using a 3-day food record. Pregnant women provided salivary samples at five time-points over a 24 h period for melatonin and cortisol assay. Consistently across the second and third trimesters, both melatonin and cortisol showed a rhythmic change over the day. Melatonin levels displayed an increment toward the night whilst cortisol levels declined over the day. Majority observed a shorter eating window (≤12 h) during the second and third trimesters (66 and 55%, respectively). Results showed 23 and 28% skipped breakfast whereas 45 and 37% ate within 2 h pre-bedtime. During the third trimester, a longer eating window was associated with lower melatonin mean (β = -0.40, p = 0.006), peak (β = -0.42, p = 0.006), and AUC_G (β = -0.44, p = 0.003). During both trimesters, a lower awakening cortisol level was observed in pregnant women who skipped breakfast (β = -0.33, p = 0.029; β = -0.29, p = 0.044). Only during the second trimester, breakfast-skipping was significantly associated with a greater cortisol amplitude (β = 0.43, p = 0.003). Findings suggest that certain chrononutrition components, particularly eating window and breakfast skipping have a significant influence on maternal melatonin and cortisol rhythm. Dietary intervention targeting these characteristics may be useful in maintaining maternal circadian rhythm.

Food combination questionnaire for Japanese: relative validity regarding food and nutrient intake and overall diet quality against the 4-day weighed dietary record

The aim of this cross-sectional study was to examine the relative validity of food and nutrient intakes and overall diet quality scores derived using a newly developed dietary assessment questionnaire (food combination questionnaire, FCQ). Dietary data were collected from 222 Japanese adults (111 for each sex) aged 30-76 years using the online FCQ and then the 4-non-consective-day weighed dietary record (DR). The median of Spearman correlation coefficients for sixteen food groups was 0⋅32 among women and 0⋅38 among men. The median of Pearson correlation coefficients for forty-six nutrients was 0⋅34 among women and 0⋅31 among men. The Pearson correlation coefficient between the total scores of Healthy Eating Index-2015 (HEI-2015) derived from the DR and FCQ was 0⋅37 among women and 0⋅39 among men. The corresponding value for the Nutrient-Rich Food Index 9.3 (NRF9.3) total scores was 0⋅39 among women and 0⋅46 among men. Bland-Altman plots for these diet quality scores showed poor agreement at the individual level, although mean difference was small for the HEI-2015 (but not NRF9.3). Similar results were obtained using the paper version of FCQ, which was answered after conducting the DR, except for somewhat high Pearson correlation coefficients for the total scores of HEI-2015 (0⋅50 among both women and men) and NRF9.3 (0⋅37 among women and 0⋅53 among men). In conclusion, this analysis may lend support to the possible use of the FCQ as a rapid dietary assessment tool in large-scale epidemiologic studies in Japan, but further refinement of this tool should be pursued.

Association between meal frequency with others and psychological distress during the COVID-19 pandemic: A cross-sectional study

Aim

Previous studies evaluated the association between eating alone and mental health mainly in older people and adolescents. This study aimed to evaluate the association between dinner frequency with others and psychological distress during the COVID-19 outbreak among the Japanese working population.

Methods

Data were acquired from a prospective online cohort study (the Employee Cohort Study in the COVID-19 pandemic in Japan) conducted in February 2021 as a cross-sectional design. Dinner frequency with others was categorized into five groups: "almost daily," "4-5 times per week," "2-3 times per week," "once per week," and "less than once per week," setting them as a predictor variable. Modified Poisson regression was performed to calculate the prevalence ratio of psychological distress with multiple imputation for missing data. Global fear and worry about COVID-19 were adjusted as a covariate.

Results

A total of 1171 participants completed the questionnaire. Respondents who ate dinner with others "almost daily" had the least psychological distress than those who ate with others "4-5 times," "2-3 times," and "once per week" in the crude model (prevalence ratio (95% CI): 1 [reference], 1.34 [1.08-1.67], 1.40 [1.15-1.69], 1.44 [1.12-1.85], respectively). The association was comparable after adjusting for global fear and worry about COVID-19.

Conclusions

Among those who ate dinner with others at least once a week, those who ate with others "almost daily" had the least psychological distress. The association was comparable after adjusting for global fear and worry about COVID-19. Further study is needed on why those who eat with others less than once a week may have a lower prevalence ratio of having mental distress.

Relative Validity of the Meal-Based Diet History Questionnaire for Estimating Nutrient Intake among Japanese Women and Men aged 30–76 Years

The purpose of this study was to examine the relative validity of the Meal-based Diet History Questionnaire (MDHQ) for estimating nutrient intake. Dietary data were obtained from 111 Japanese women and 111 Japanese men, using the online MDHQ and the 4-non-consecutive-day weighed dietary record (DR). The number of nutrients (total n = 46) showing no significant mean differences between estimates from the online MDHQ and DR (with energy adjustment by the density model) was 17 among women and 12 among men. The median value (25th and 75th percentiles) of the Pearson correlation coefficients between the online MDHQ and DR estimates was 0.54 (0.35–0.57) among women and 0.45 (0.25–0.53) among men. Bland–Altman plots for energy-providing nutrients indicated wide limits of agreement (and proportional bias for protein) with overall underestimation of protein and fat and overestimation of carbohydrate by the online MDHQ. Similar results were found when the paper version of the MDHQ (completed after the DR) was examined. For example, the median value of the Pearson correlation coefficients was 0.54 for women and 0.45 for men. This study suggests that the MDHQ has an acceptable ability to rank individuals according to intakes of a wide range of nutrients.

Relative Validity of Food Intake in Each Meal Type and Overall Food Intake Derived Using the Meal-Based Diet History Questionnaire against the 4-Day Weighed Dietary Record in Japanese Adults

We examined the relative validity of food intake for each meal type (breakfast, lunch, dinner, and snacks) and overall food intake obtained through the Meal-based Diet History Questionnaire (MDHQ). In total, 222 Japanese adults (111 for each sex) aged 30–76 years completed the web version of the MDHQ and then the 4-non-consecutive-day weighed dietary record (DR). The number of major food groups (n = 24 in total) for which no statistically significant difference was observed between median intakes estimated using the DR and MDHQ ranged from 8 (snacks) to 12 (dinner) among women, and from 8 (breakfast) to 13 (lunch) among men. The median values of the Spearman’s correlation coefficients between the MDHQ and DR estimates ranged from 0.28 (dinner) to 0.54 (breakfast) among women, and from 0.24 (dinner) and 0.60 (breakfast) among men. Bland–Altman analyses generally showed wide limits of agreement and proportional bias. Similar results were obtained using the paper version of the MDHQ, which was completed after conducting the DR. In conclusion, the MDHQ has a satisfactory ability to estimate median intake and rank individuals according to consumption for many food groups, despite a limited ability to estimate food group intakes on an individual level.

Association of daily nutrient intake with breakfast and snack consumption among young Japanese adults aged 20-39 years: data from the 2012 National Health and Nutrition Survey

Eating frequency has been associated with nutrient intake and diet quality. The aim of this study was to examine the association between daily nutrient and food group intake and consumption of breakfast and/or snacks among young Japanese adults, as secondary analysis of the 2012 National Health and Nutrition Survey in Japan involved 1420 men and 1659 women aged 20-39 years. Dietary intake data were collected using a one-day semi-weighed household dietary record. Participants were classified into four groups based their breakfast and snack consumption, defined as the consumption of any food or beverage that contained energy based on participant-defined eating occasions; both breakfast and snack consumption (B+S+), breakfast consumption without snacking (B+S-), breakfast skipping and snack consumption (B-S+) and breakfast skipping without snacking (B-S-). The proportion of breakfast skippers among men and women was 11·8 % and 6·6 %, whereas that of snack consumers among men and women was 55·3 % and 68·2 %, respectively. Energy, Mg potassium (in both sexes), vitamin B2, Ca, (only men) and folate and dietary fibre (only women) intakes were higher among breakfast and snack consumers than in the B+S- group. The nutrient intake level of the B+S- group was similar to that of the B-S+ group, whereas the B-S- group had lower energy (both sexes), Cu, dietary fibre and potassium (only women) intakes than the B+S- group. Snack consumption could supplement nutrients that may not be adequately consumed by three meals among young Japanese adults.

Eating patterns in a nationwide sample of Japanese aged 1-79 years from MINNADE study: eating frequency, clock time for eating, time spent on eating and variability of eating patterns

OBJECTIVE

Although there is growing evidence suggesting that eating patterns are important determinants of health status, comprehensive information on patterning of eating behaviours is almost lacking. The aim of this cross-sectional study was to describe eating patterns in Japan.

DESIGN

Information on actual eating behaviours was collected using 2-d dietary record in each season over a year (total 8 d). Eating occasions were defined as any discrete intake occasion (with a discrete start clock time and name) except for eating occasions consisting of water only, which were excluded.

SETTING

Japan.

PARTICIPANTS

A nationwide sample of 4032 Japanese aged 1-79 years.

RESULTS

The mean value of eating frequency of meals (i.e. breakfast, lunch and dinner), snacks and total eating occasions was 2·94, 1·74 and 4·68 times/d, respectively. The mean clock time for the start of breakfast, lunch and dinner was 07.24, 12.29 and 19.15 h, respectively. The mean time spent consuming breakfast, lunch, dinner and snacks was 19, 25, 34 and 27 min/d, respectively. On average, variability (i.e. average of absolute difference from mean) of meal frequency was small compared with that of snack frequency and total eating frequency. Both mean variability of clock time for the start of eating (<1 h) and mean variability of time spent on meals (<10 min/d) were also small. Conversely, mean variability of time spent on snacks was large (>18 min/d).

CONCLUSION

The present findings serve as both a reference and an indication for future research on patterning of eating behaviours.

Development of a Digital Photographic Food Atlas as a Portion Size Estimation Aid in Japan

This study aimed to develop a digital photographic food atlas as a portion size estimation aid. Commonly consumed foods were identified from the 5512-day weighed dietary records of 644 Japanese adults. Portion sizes were determined based on the market research and distribution of food consumption in the dietary records. Each food item was classified into one of two photo types: a series of photographs showing gradually increasing portion sizes or guide photographs representing a range of portion sizes and food varieties in one photograph. Photographs of the food were taken at an angle of 42°, along with appropriate reference objects such as chopsticks. In total, 209 food and dish items were included in the food atlas. Series of photographs were taken for 105 items that are not usually served in predetermined amounts (e.g., rice and pasta), whereas guide photographs were taken for 104 items usually served in predetermined amounts (e.g., bananas and cookies). Moreover, photographs were taken for 12 kinds of household measurement items, such as cups and glasses. The food atlas could be a valuable tool for estimating the portion size in dietary surveys. Evaluating the validity of this food atlas for portion size estimation is warranted.

Food Choice Values and Food Literacy in a Nationwide Sample of Japanese Adults: Associations with Sex, Age, and Body Mass Index

This cross-sectional study of 2231 Japanese adults described food choice values and food literacy in relation to sex, age, and body mass index. We assessed eight food choice values (accessibility, convenience, health/weight control, tradition, sensory appeal, organic, comfort, and safety, using a 25-item scale), as well as food literacy, which was characterized by nutrition knowledge (using a validated 143-item questionnaire), cooking and food skills (using 14- and 19-item scales, respectively), and eight eating behaviors (hunger, food responsiveness, emotional overeating, enjoyment of food, satiety responsiveness, emotional undereating, food fussiness, and slowness in eating, using the 35-item Adult Eating Behavior Questionnaire). Females had higher means of all the variables than males, except for food fussiness. Compared to participants aged 19-39 and/or 40-59 years, those aged 60-80 years had low means of some food choice values (accessibility, convenience, sensory appeal, and comfort), nutrition knowledge, and all the food approach behaviors (hunger, food responsiveness, emotional overeating, and enjoyment of food) and high means of other food choice values (tradition, organic, and safety) and slowness in eating. Age was inversely associated with cooking and food skills in males, whereas the opposite was observed in females. The associations with body mass index were generally weak. These findings serve as both a reference and an indication for future research.

Web-Based Personalized Nutrition System for Delivering Dietary Feedback Based on Behavior Change Techniques: Development and Pilot Study among Dietitians

Given the complex and varied nature of individual characteristics influencing dietary behaviors, personalized dietary advice may be more effective than generalized “one-size-fits-all” advice. In this paper, we describe a web-based personalized nutrition system for improving the quality of overall diet in the general adult population. The development process included identification of appropriate behavior change techniques, modification of dietary assessment method (Meal-based Diet History Questionnaire; MDHQ), selection of dietary components, and a personalized dietary feedback tool. A pilot study was conducted online among 255 dietitians. Each completed the MDHQ, received his/her own dietary feedback report, and evaluated the relevance of the report based on 12 questions using a 5-point Likert scale from “totally disagree” (score 1) to “totally agree” (score 5). The mean value of overall acceptability score of dietary feedback report was 4.2. The acceptability score was, on average, higher in plausible energy reporters (compared with implausible energy reporters), participants who printed out the report (compared with those who did not), and those spending ≥20 min to read the report (compared with those spending <20 min). This is the first attempt to develop a web-based personalized nutrition system in Japan, where dietitians were broadly supportive of the dietary feedback report.

Identification of Dish-Based Dietary Patterns for Breakfast, Lunch, and Dinner and Their Diet Quality in Japanese Adults

We identified dish-based dietary patterns for breakfast, lunch, and dinner and assessed the diet quality of each pattern. Dietary data were obtained from 392 Japanese adults aged 20–69 years in 2013, using a 4 d dietary record. K-means cluster analysis was conducted based on the amount of each dish group, separately for breakfasts (n = 1462), lunches (n = 1504), and dinners (n = 1500). The diet quality of each dietary pattern was assessed using the Healthy Eating Index 2015 (HEI-2015) and Nutrient-Rich Food Index 9.3 (NRF9.3). The extracted dietary patterns were as follows: ‘bread-based’ and ‘rice-based’ for breakfast; ‘bread’, ‘rice-based’, ‘ramen’, ‘udon/soba’, and ‘sushi/rice bowl dishes’ for lunch; and ‘miscellaneous’, ‘meat dish and beer’, and ‘hot pot dishes’ for dinner. For breakfast, the HEI-2015 and NRF9.3 total scores were higher in the ‘rice-based’ pattern than the ‘bread-based’ pattern. For lunch, the HEI-2015 and NRF9.3 total scores were relatively high in the ‘rice-based’ pattern and low in the ‘ramen’ pattern. For dinner, the HEI-2015 total score was the highest in the ‘meat dish and beer’ pattern, and the NRF9.3 total score was higher in the ‘hot pot dishes’ than the ‘miscellaneous’ pattern. These results suggested that breakfast, lunch, and dinner have distinctive dietary patterns with different diet qualities.