ABSTRACT
Aims/Introduction
To determine the association of irregular dietary habits with HbA1c and body mass index (BMI) in people with diabetes.
Materials and Methods
We included 4,421 people with diabetes aged 20–74 years (type 1 diabetes (T1D), 19.1%) who answered a questionnaire at mealtime. Adjusted least square means in HbA1c and BMI in patients with irregular dietary habits: “irregular mealtimes (irregular),” “skipping breakfast (SB),” and “late dinner (LD)” were compared to those with “regular dietary habits (regular).” Multivariable logistic regression analyses were performed to examine the association of irregular dietary habits with HbA1c ≥ 7% and BMI ≥25 kg/m2.
Results
HbA1c was significantly higher for “irregular” in both sexes and for “LD” in women than those of “regular” in people with T1D. HbA1c was significantly higher for “LD,” and BMI was higher for almost all irregular dietary habits than those of “regular” in people with type 2 diabetes (T2D). Odds ratios (ORs) for HbA1c ≥7% were 3.20 (95% confidence interval (CI), 1.30–7.89) for T1D women with “irregular” and 1.73 (1.20–2.49) and 2.20 (1.14–3.65) for T2D men and women with “LD,” respectively. ORs for BMI ≥25 kg/m2 were 1.60 (95% CI, 1.15–2.22) for T2D men with “irregular” and 1.43 (1.02–2.01) and 2.11 (1.21–3.65) for T2D women and men with “LD,” respectively.
Conclusions
Irregular mealtimes are associated with poor glycemic control in T1D women and are associated with obesity in T2D men. Furthermore, a late dinner was associated with high HbA1c levels and BMI in people with T2D.
Keywords: Body mass index, Dietary habits, HbA1c
To determine the association between irregular dietary habits and HbA1c and body mass index (BMI) in people with diabetes.
INTRODUCTION
Regular and healthy dietary habits are important for the management of lifestyle‐related diseases such as diabetes. However, in recent years, people have often skipped meals or had irregular mealtimes owing to the amount and type of work. According to the National Health and Nutrition Survey of 2019, the percentage of obese persons [body mass index (BMI) ≥ 25 kg/m2] was 33.0% for men and 22.3% for women 1 . Furthermore, 15.5% of men and 9.1% of women skipped breakfast 1 . According to the 2008 National Health and Nutrition Survey, approximately 12% of Japanese aged 15 years older have dinner after 9 p.m. 2 . Among adults, the percentages of those who had dinner after 9 p.m. were 28.6% for men in their 20s, 33.9% for men in their 30s, 29.8% for men in their 40s, and 17.4% for women in their 20s 2 . In addition, according to the 2011 Basic Survey on Social Life, 10.6% of the participants had dinner after 9 p.m., indicating that there has been no improvement in late dinner time 3 .
Irregular dietary habits are associated with type 2 diabetes mellitus (T2D) and obesity 4 , 5 . Previous studies have shown that skipping breakfast causes a significant increase in the peak blood glucose level after lunch (the second meal phenomenon) 6 , and that late dinner is associated with poor glycemic control in T2D 7 , 8 . There have been several studies on the relationship of dietary habits with glucose metabolism, and obesity in people with T2D; however, there have been few studies on sex differences of dietary habits with glycemic and weight control in people with T2D. In addition, few studies have investigated the association of dietary habits with glycemic control or obesity in people with type 1 diabetes (T1D) 9 , 10 . Therefore, we investigated the association between irregular dietary habits (skipping breakfast, eating dinner late, and irregular mealtimes), glycemic control, and weight in people with T1D and T2D.
MATERIALS AND METHODS
Study participants
A questionnaire on the dietary habits was administered to individuals aged 20–74 years with T1D and T2D who participated in a large cohort study (DIACET) at the Tokyo Women's Medical University Diabetes Center from 2012 to 2013. We obtained 5,258 responses with the response rate of 90.9%. Of these, 844 (299 males and 545 females) had T1D and 3,577 (2,132 males and 1,445 females) had T2D after excluding those with pregnancy (n = 10), stage 4 nephropathy or post‐renal transplantation (n = 136), missing data (n = 554), missing lunch or dinner (n = 57) and overlapping two or more of following; irregular mealtime, skipping breakfast or late dinner (n = 80). A total of 4,421 people (844 with T1D and 3,577 with T2D) were included in the analysis.
Measurements
DIACET is an ongoing single‐center prospective observational cohort study targeting Japanese patients with diabetes who visit the Division of Diabetes and Metabolism at Tokyo Women's Medical University Hospital.
In the DIACET, self‐administered questionnaires were distributed at the time of the examination and collected either by bringing them at the next visit or by sending them through mail. For eating habits, the following question was asked. There were no questions about snacks and late‐night meals.
“What time did you start your meal at least three times per week over a recent month?”
Breakfast time: 1. 4:00–5:00, 2. 5:00–6:00, 3. 6:00–7:00, 4. 7:00–8:00, 5. 8:00–9:00, 6. after 9:00 a.m., 7. irregular, 8. skip.
Lunch time: 1. 11:00–12:00, 2. 12:00–13:00, 3. 13:00–14:00, 4. 14:00–15:00, 5. after 15:00 p.m., 6. irregular, 7. skip.
Dinner time: 1. 17:00–18:00, 2. 18:00–19:00, 3. 19:00–20:00, 4. 20:00–21:00, 5. 21:00–22:00, 6. after 22:00 p.m., 7. irregular, 8. skip.
Based on the responses to each question, eating habits were classified into four categories: “regular dietary habits,” “irregular mealtime,” “skipping breakfast,” and “late dinner”. Regular dietary habits were defined as not missing meals, regular mealtimes, and dinner time before 9:00 p.m. 2 . Irregular mealtime was defined as one or more of the three meals at irregular times (selected ‘7’ in breakfast or dinner and ‘6’ in lunch). Late dinner was defined as dinner after 9 p.m. 2 .
Data on age, sex, type of diabetes, anthropometric measurements, HbA1c levels, duration of diabetes, and the use of glucose‐lowering agents were obtained from medical records. BMI was calculated as weight divided by height in meters squared (kg/m2). HbA1c values were measured using high‐performance liquid chromatography (Adams A1c HA‐8160; Arkray) and reported as percentages according to the National Glycohemoglobin Standardization Program 11 .
Statistical analysis
Data were analyzed and reported separately for each type of diabetes. Continuous variables were presented as means ± SD, and categorical data were expressed as proportions. A χ2‐test was used to compare proportions, and Mann–Whitney U‐test was employed to compare the continuous variables between T1D and T2D clinical measurements.
A one‐way anova was performed to compare the mean values of age, duration of diabetes, HbA1c, BMI, and insulin use rate (T2D only) between “regular dietary habits” and the three irregular dietary habits of “irregular mealtime,” “skipping breakfast,” and “late dinner” by type of diabetes and sex. In those cases where there were significant differences, we further compared “regular dietary habits” as a reference with the other three dietary habits by using the Dannett's test.
Next, analysis of covariance (ancova) was used to calculate the least squares mean changes in HbA1c and BMI between “regular dietary habits” and the other three patterns of dietary habits, after adjustment for the following covariates: age, HbA1c, BMI, duration of diabetes, and insulin use (only T2D).
To understand the effect on poor glycemic control (HbA1c ≥ 7%) or obesity (BMI ≥ 25 kg/m2) of each dietary habit compared to “regular dietary habits”, multivariable logistic regression analyses were performed to calculate odds ratios (ORs) and their 95% confidence intervals (95% CIs). To determine the effects of multicollinearity on logistic regression analyses and subsequent conclusion, Kendall's tau rank correlation was used. The Hosmer‐Lemeshow test was used to evaluate the goodness‐of‐fit of the logistic regression analyses. A P‐value of >0.05 was considered a good fit.
All statistical analyses were performed using the R software (version 4.3.1; R Foundation for Statistical Computing, Austria). The P‐values were based on two‐sided tests, and the cutoff point for statistical significance was set at 0.05.
Ethical considerations
This study was approved by the Ethics Review Committee of Tokyo Women's Medical University (approval no. 2481‐R3; dated November 4, 2023). All the clinical investigations were conducted in accordance with the tenets of the Declaration of Helsinki.
RESULTS
Characteristics of study participants
The mean age, BMI, and HbA1c were 58 years, 25.0 kg/m2, and 7.5%, respectively. The clinical characteristics of the patients are summarized in Table 1. Participants with T1D were younger and had a lower proportion of men, a longer duration of diabetes, lower BMI, and higher HbA1c levels than those with T2D (P < 0.001). The distribution of each eating habit was as follows: “regular dietary habits”, 82.7%; “irregular mealtimes”, 7.4%; “skipping breakfast”, 2.1%; and “late dinner”, 7.8%. The proportion of late dinners was significantly higher in patients with T1D than in those with T2D (P < 0.001).
Table 1.
Characteristics of study participants
| Type 1 diabetes | Type 2 diabetes | P value | |
|---|---|---|---|
| N | 844 | 3,577 | |
| Age, years | 46 ± 14 | 61 ± 10 | <0.001 |
| Sex, men % | 299 (35.4) | 2,132 (59.6) | <0.001 |
| Duration of diabetes, years | 18 ± 12 | 14 ± 10 | <0.001 |
| BMI, kg/m2 | 22.8 ± 3.3 | 24.9 ± 4.4 | <0.001 |
| HbA1c, % | 7.7 ± 1.3 | 7.4 ± 1.2 | <0.001 |
| Insulin, N (%) | 844 (100) | 1,291 (36.2) | <0.001 |
| Non‐insulin glucose lowering agents, N (%) | |||
| Metformin | – | 1,145 (32.1) | |
| Sulfonylurea | – | 1,252 (35.1) | |
| DPP‐4 inhibitors | – | 1,405 (39.3) | |
| Thiazolidinediones | – | 317 (8.9) | |
| GLP‐1 RAs | – | 42 (1.2) | |
| α‐GIs | 35 (4.2) | 634 (17.8) | <0.001 |
| Glinides | – | 67 (1.9) | |
| Dietary habits, N (%) | |||
| Regular dietary habits | 655 (77.6) | 3,000 (83.9) | <0.001 |
| Irregular mealtime | 67 (7.9) | 261 (7.3) | 0.568 |
| Skipping breakfast | 19 (2.3) | 72 (2.0) | 0.741 |
| Late dinner after 9 p.m. | 103 (12.2) | 244 (6.8) | <0.001 |
Data are presented as mean ± SD. BMI, body mass index; DPP‐4, dipeptidyl peptidase 4; GLP‐1 RAs, glucagon‐like peptide 1 receptor agonists; α‐GIs, α‐glucosidase inhibitors.
Table 2 shows participants' characteristics by dietary habits, type of diabetes, and sex. For T1D, men in the group of “skipping breakfast” and “late dinner” and women in the group of “irregular mealtime” were significantly younger than those in the group of “regular dietary habits”. Men and women with T1D in the group of “late dinner” showed significantly shorter duration of diabetes than those in the group of “regular dietary habits”. For T2D, men and women in the group of three irregular dietary habits showed significantly younger age and higher BMI than those in the group of “regular dietary habit”, except for “skipping breakfast” in men. Men and women in the group of “late dinner” showed significantly higher HbA1c than those in the group of “regular dietary habits”.
Table 2.
Characteristics of study participants by dietary habits
| Regular dietary habits (Reference) | Irregular mealtime | Skipping breakfast | Late dinner after 9 p.m. | |
|---|---|---|---|---|
| Type 1 diabetes | ||||
| Men | ||||
| N (%) | 204 (68.2) | 21 (7.0) | 9 (3.0) | 65 (21.7) |
| Age, years | 51 ± 14 | 45 ± 8 | 37 ± 16** | 44 ± 10** |
| BMI, kg/m2 | 23.2 ± 3.2 | 23.2 ± 3.4 | 22.2 ± 3.3 | 23.7 ± 3.4 |
| HbA1c, % | 7.6 ± 1.2 | 8.3 ± 1.8* | 7.4 ± 0.7 | 7.4 ± 1.3 |
| Duration of diabetes, years | 20 ± 12 | 17 ± 13 | 13 ± 11 | 11 ± 9*** |
| Women | ||||
| N (%) | 451 (82.8) | 46 (8.4) | 10 (1.8) | 38 (7.0) |
| Age, years | 46 ± 14 | 36 ± 11*** | 41 ± 7 | 43 ± 13 |
| BMI, kg/m2 | 22.6 ± 3.3 | 22.3 ± 3.5 | 23.4 ± 4.5 | 23.2 ± 3.5 |
| HbA1c, % | 7.7 ± 1.6 | 8.2 ± 1.7 | 7.3 ± 1.0 | 8.2 ± 2.1 |
| Duration of diabetes, years | 20 ± 12 | 17 ± 11 | 15 ± 12 | 14 ± 8* |
| Type 2 diabetes | ||||
| Men | ||||
| N (%) | 1,724 (80.9) | 172 (8.1) | 60 (2.8) | 176 (8.2) |
| Age, years | 63 ± 9 | 57 ± 11*** | 58 ± 10*** | 54 ± 9*** |
| BMI, kg/m2 | 24.6 ± 3.9 | 26.5 ± 4.6*** | 25.4 ± 3.6 | 26.0 ± 4.2*** |
| HbA1c, % | 7.3 ± 1.1 | 7.3 ± 1.2 | 7.5 ± 1.4 | 7.6 ± 1.3*** |
| Duration of diabetes, years | 15 ± 10 | 14 ± 10 | 11 ± 8* | 14 ± 9 |
| Insulin, N (%) | 592 (34.4) | 53 (31.0) | 15 (25.0) | 52 (29.5) |
| Women | ||||
| N (%) | 1,276 (88.3) | 89 (6.2) | 12 (0.8) | 68 (4.7) |
| Age, years | 62 ± 10 | 57 ± 12*** | 50 ± 13*** | 54 ± 12*** |
| BMI, kg/m2 | 24.6 ± 4.7 | 26.6 ± 5.5*** | 28.3 ± 7.2* | 26.5 ± 6.0** |
| HbA1c, % | 7.5 ± 1.2 | 7.8 ± 1.5 | 7.4 ± 0.5 | 8.0 ± 1.6** |
| Duration of diabetes, years | 14 ± 9 | 15 ± 10 | 17 ± 9 | 14 ± 9 |
| Insulin, N (%) | 515 (40.4) | 28 (31.8) | 2 (16.7) | 34 (50.7) |
Data are presented as mean ± SD. *P < 0.05, **P < 0.01, ***P < 0.001 vs regular dietary habits. BMI, body mass index.
Comparison of adjusted HbA1c and BMI by dietary habits in T1D and T2D
The adjusted means of HbA1c and BMI for each dietary habit were compared according to the type of diabetes and sex (Table 3). In T1D, adjusted HbA1c was significantly higher in the group of “irregular mealtime” for both sexes and in the group of “late dinner” for women than the group of “regular dietary habits”. In T2D, adjusted HbA1c was significantly higher in the group of “late dinner” for both sexes than the group of “regular dietary habits”. The adjusted BMI was significantly higher in almost all three irregular dietary habits than the group of “regular dietary habits”, except for the group of “skipping breakfast” in men.
Table 3.
Adjusted means of HbA1c and body mass index by dietary habits
| Regular dietary habits (Reference) | Irregular mealtime | Skipping breakfast | Late dinner after 9 p.m. | |
|---|---|---|---|---|
| Type 1 diabetes † | ||||
| Men | ||||
| HbA1c, % | 7.6 (0.2) | 8.4 (0.3)** | 7.6 (0.4) | 7.6 (0.2) |
| BMI, kg/m2 | 23.8 (0.4) | 23.6 (0.8) | 22.9 (1.1) | 24.5 (0.5) |
| Women | ||||
| HbA1c, % | 7.9 (0.2) | 8.5 (0.3)* | 7.6 (0.5) | 8.5 (0.3)* |
| BMI, kg/m2 | 23.2 (0.4) | 22.6 (0.6) | 24.2 (1.1) | 23.8 (0.7) |
| Type 2 diabetes ‡ | ||||
| Men | ||||
| HbA1c, % | 7.4 (0.1) | 7.3 (0.1) | 7.5 (0.1) | 7.6 (0.2)*** |
| BMI, kg/m2 | 24.7 (0.1) | 25.9 (0.3)*** | 24.6 (0.4) | 24.8 (0.3)*** |
| Women | ||||
| HbA1c, % | 7.6 (0.1) | 7.7 (0.1) | 7.3 (0.3) | 7.9 (0.1)*** |
| BMI, kg/m2 | 24.7 (0.1) | 25.8 (0.5)*** | 27.0 (1.3)** | 25.2 (0.5)*** |
Data are presented as least square means (standard error). *P < 0.05, **P < 0.01, ***P < 0.001 vs regular dietary habits.
Adjusted for age, duration of diabetes in type 1 diabetes.
Adjusted for age, duration of diabetes and insulin use in type 2 diabetes.
BMI, body mass index.
Association of each dietary habit with poor glycemic control and obesity
Table 4 shows the association of each dietary habit with HbA1c ≥7% and BMI ≥25 kg/m2. As for T1D, the adjusted OR of HbA1c ≥7% for “irregular mealtime” was 3.20 (95% CI 1.30–7.89) in women with T1D.
Table 4.
Association between dietary habits and high level of HbA1c and body mass index
| Regular dietary habits | Irregular mealtime | Skipping breakfast | Late dinner after 9 p.m. | |
|---|---|---|---|---|
| Multivariable ORs (95%CI) | Multivariable ORs (95%CI) | Multivariable ORs (95%CI) | Multivariable ORs (95%CI) | |
| Type 1 diabetes † | ||||
| Men | ||||
| HbA1c ≥ 7% | 1.00 (reference) | 2.34 (0.74–7.43) | 2.44 (0.46–12.92) | 0.96 (0.50–1.83) |
| BMI ≥ 25 kg/m2 | 1.00 (reference) | 0.62 (0.20–1.99) | 0.43 (0.05–3.59) | 1.69 (0.85–3.37) |
| Women | ||||
| HbA1c ≥ 7% | 1.00 (reference) | 3.20 (1.30–7.89) | 1.09 (0.27–4.44) | 1.30 (0.60–2.79) |
| BMI ≥ 25 kg/m2 | 1.00 (reference) | 0.57 (0.24–1.35) | 1.68 (0.42–6.73) | 0.93 (0.40–2.13) |
| Type 2 diabetes ‡ | ||||
| Men | ||||
| HbA1c ≥ 7% | 1.00 (reference) | 0.88 (0.63–1.23) | 1.27 (0.74–2.20) | 1.73 (1.20–2.49) |
| BMI ≥25 kg/m2 | 1.00 (reference) | 1.60 (1.15–2.22) | 1.02 (0.59–1.75) | 1.43 (1.02–2.01) |
| Women | ||||
| HbA1c ≥ 7% | 1.00 (reference) | 1.16 (0.71–1.89) | 1.37 (0.35–5.38) | 2.20 (1.14–4.23) |
| BMI ≥ 25 kg/m2 | 1.00 (reference) | 1.26 (0.79–2.00) | 2.08 (0.60–7.25) | 2.11 (1.21–3.65) |
Adjusted for age, duration of diabetes in type 1 diabetes.
Adjusted for age, duration of diabetes and insulin use in type 2 diabetes.
BMI, body mass index; CI, confidence interval; OR, odds ratio.
As for T2D, the adjusted ORs of HbA1c ≥7% for “late dinner” were 1.73 (95% CI 1.20–2.49) in men and 2.20 (95% CI 1.14–3.65) in women. The adjusted OR of BMI ≥25 kg/m2 for “irregular mealtime” was 1.60 (95% CI 1.15–2.22) in men and respective values for “late dinner” were 1.43 (95% CI 1.02–2.01) in men and 2.11 (95% CI 1.21–3.65) in women. Though there was a statistically significant correlation between HbA1c and BMI by Kendall's tau rank correlation, this correlation was weak (correlation coefficient 0.118, P = 0.03 in T1D men, 0.090, P = 0.003 in T1D women and 0.153, P < 0.001 in T2D men and women). The results of Hosmer‐Lemeshow test were all P > 0.05, and the discriminant accuracy rate were 80.5–86.2% in T1D and 74.4–83.9% in T2D, indicating that the model was well‐fitted.
DISCUSSION
This cross‐sectional study showed that “irregular mealtime” in women with T1D and “late dinner” in men and women with T2D were associated with poor glycemic control. Further, “irregular mealtimes” in men with T2D and “late dinner” in men and women with T2D were associated with obesity.
One of the reasons for the discrepancies in results between T1D and T2D is the difference in dietary behavior and preference. People with T1D have a higher stage of dietary behavior modification, are less likely to eat out, and are more likely to pay attention to their diet than those with T2D 12 . In the present study, there was no data on the dietary content, which may have influenced the results. Furthermore, people with T1D have greater glycemic variability, which affects HbA1c, than those with T2D due to the depletion of insulin secretion 13 . In addition, people with T1D tend to be less obese than those with T2D, suggesting that the effects of dietary habits on body weight may differ. In the present case, the average BMI people with T1D and T2D was 22.8 and 24.9 kg/m2.
The 2008 National Health and Nutrition Survey reported that people in their prime working years have dinner at late hours 2 . In the present study, the proportion of late dinners was high in the 30–50's age group. A recent study reported that the peak blood glucose level was 18% higher on average when dinner was consumed 1 h before bedtime 14 . A late dinner increases insulin resistance due to increased melatonin secretion and elevated free fatty acids caused by prolonged hunger 15 , 16 . Moreover, since meal‐induced heat production is 50% lower at night compared to daytime and energy expenditure is reduced at night, late evening meals lead to elevated blood glucose and weight gain 17 , 18 . Our results are consistent with those of previous reports 7 , 8 that showed an association of late dinner with poor glycemic control, and high BMI in people with T2D. A previous report showed that having dinner at different times, such as having carbohydrates early in the evening and vegetables and main dishes late at night after returning home, suppresses the increase in blood glucose levels in patients with T2D 19 . Therefore, changes in meal timing or content might improve hyperglycemia and obesity.
Irregular mealtimes may affect circadian rhythms. The suprachiasmatic nucleus, which controls the circadian rhythm, regulates nutrient metabolism and energy utilization throughout the day. When this rhythm is misaligned, insulin resistance increases, leading to elevated blood glucose levels 20 . Studies have shown that the rhythm of the daily eating‐fasting cycle is closely related to the rhythm of mRNAs and proteins, which regulate glucose metabolism and mitochondrial function 21 , 22 . A shift in the circadian rhythm of shift workers causes a decrease in β‐cell function 23 , and the effect on the pancreatic circadian clock may affect insulin secretion 24 . Furthermore, irregular mealtimes may cause mismatches between the timing of insulin injections and meals. This mismatch may cause large fluctuations in blood glucose levels, leading to high HbA1c levels 25 .
Skipping breakfast is known to increase blood glucose levels after lunch 6 , and HbA1c levels increase after skipping breakfast concomitant with late dinner 7 . In the present study, no significant association was noted between skipping breakfast and poor glycemic control. One possible reason for this is that the rate of skipping breakfast was lower in this study than in previous reports. In addition, the fact that skipping breakfast regularly does not result in a second meal phenomenon has been recently reported 26 . Therefore, the effect of regularly skipping breakfast on HbA1c might have been small in this study. However, skipping breakfast has been reported to cause weight gain 27 and is associated with high HbA1c levels in young people with T1D 9 ; however, the chronic effects of skipping breakfast on glucose homeostasis and energy metabolism remain unclear.
This study had several limitations. First, this study used a cross‐sectional design; therefore, future longitudinal analyses of the association of dietary habits with glycemic and weight control are required. Second, diet details were not available; therefore, we could not examine the effects of caloric and nutrition balance and snacking. Mealtimes affect the quality of food and adherence to medications. It has been reported that late dinner can lead to overeating 28 . These are related to poor glycemic and weight control. However, it has also been reported that even with the same meal contents, consuming in late dinner led to postprandial hyperglycemia 19 . Third, we could not examine the effects of factors such as physical activity and sleep timing, due to the lack of information on the participant's occupation. Fourth, because the data were obtained 10 years prior, the administration rates of GLP‐1 receptor agonists and SGLT2 inhibitors, which are now widely used, were either low or absent. However, small doses of diabetic medication would be better at reducing the effects of the drugs on the influence of dietary habits. Blood glucose management targets have changed over the years, therefore, there may be differences from the present; however, according to the recent average values of HbA1c (7.7% in T1D and 7.1% in T2D) and BMI (23.4 kg/m2 in T1D and 24.7 kg/m2 in T2D) 29 , it was thought that there had been no significant changes.
Despite these limitations, this study clarified the association among irregular dietary habits, glycemic control, and body weight in people with T1D and T2D.
Irregular mealtimes in women with T1D and late dinners in men and women with T2D were associated with poor glycemic control. Irregular mealtimes in men with T2D and late dinners in both men and women with T2D are associated with obesity. Further studies on how and what people should eat when they cannot improve their mealtime due to their work schedules are needed.
FUNDING
The authors declare that no funds, grants, or other support was received during the preparation of this manuscript.
DISCLOSURE
T Nakagami received personal fees from Sanwa Kagaku Kenkyusho Co. Ltd., Novo Nordisk Pharma Ltd., Japan, Eli Lily Japan KK, Sanofi K.K., Sumitomo Pharma, and Boehringer Ingelheim Japan, Inc. Other authors declare no conflicts of interest.
Ethics approval and consent to participate: The study was approved by the Ethics Review Committee of Tokyo Women's Medical University (approval no. 2481‐R3; date: November 4, 2023). All the clinical investigations were conducted in accordance with the tenets of the Declaration of Helsinki.
Informed consent: Informed consent was obtained from all the participants.
Registry and the registration no. of the study/trial: N/A.
Animal studies: N/A.
CONSENT FOR PUBLICATION
Not applicable.
ACKNOWLEDGMENTS
Not applicable.
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