Soy Intake and Risk of Type 2 Diabetes Among Japanese Men and Women: JACC Study

The evidence on the protective effects of soy foods against type 2 diabetes has been inconsistent. We thought to examine the association between the dietary intakes of soy and the risk of diabetes in a prospective study encompassing 21,925 healthy Japanese men and women aged 40–79 years. A validated self-administered food frequency questionnaire determined the intakes of soy, and their associations with risk of type 2 diabetes were evaluated by the logistic regression analysis. During the 5-year follow-up period, we observed 593 new cases of type 2 diabetes (302 in men and 291 in women). There was no association between dietary intakes of soy foods and the risk of type 2 diabetes among men. Whereas among women, higher tofu intake was inversely associated with risk of type 2 diabetes; the multivariable odds ratios (ORs) of type 2 diabetes were 0.92 (95% CI: 0.69–1.21) for 3–4 times per week and 0.67 (95% CI: 0.49–0.94) for almost daily (p-trend = 0.03) in reference to those consuming tofu less than 3 times per week. Intakes of boiled beans and miso soup were not associated with the risk in both genders. The inverse association tended to be more evident among overweight women and postmenopaused women. In conclusion, the frequency of tofu intake was inversely associated with the risk of type 2 diabetes among women.

Effects of luteolin-rich chrysanthemum flower extract on purine base absorption and blood uric acid in Japanese subjects

Background and objective: Chrysanthemum flowers are consumed as fresh condiments, herbal teas, and processed foods in Japan and Taiwan. They contain luteolin as a major polyphenol and are traditionally used for eye care. We previously demonstrated that the ingestion of Chrysanthemum flower extract (CFE) for 1 month reduced serum uric acid levels. However, the findings obtained were considered to be biased because the study was performed by a CFE manufacturer. Therefore, we herein conducted a clinical trial on CFE on a larger scale and examined its effects on purine base absorption from the intestines, which represents an effective approach for reducing serum uric acid levels. Methods: Both studies were performed as randomized, double-blind, placebo-controlled trials and CFE (100 mg) containing 1 mg of luteolin was used as the active sample. We enrolled 44 healthy Japanese men and women with 6.0 to 7.9 mg/dL serum uric acid. All subjects were randomly allocated to an active group (n=22) or placebo group (n=22) using a computerized random number generator. In the purine base absorption study, CFE was ingested with a purine base-rich diet and serum uric acid levels were measured chronologically. In the 12-week consecutive ingestion study, CFE or placebo was administered between January and April 2021. Serum uric acid levels after 12 weeks were assessed as the primary outcome, and uric acid were measured before and after 4 weeks of the intervention as secondary outcomes. Blood, urine and body parameters were examined to evaluate the safety of CFE. Results: Thirty-nine subjects completed the trial, and the per protocol set comprised 18 and 21 subjects in the active and placebo groups, respectively. In the single dosing study of CFE on subjects loaded by the purine base-rich diet, no significant changes were observed between the CFE and placebo groups. On the other hand, in the 12-week ingestion study, serum uric acid levels were significantly lower in the CFE group than in the placebo group. Laboratory tests revealed no abnormalities to suggest any side effects of CFE.Conclusions: CFE (100 mg/day) containing 1 mg of luteolin reduced serum uric acid levels. CFE may be beneficial for improving hyperurichemia. Trial Registration: UMIN-CTR: UMIN000042327Foundation: The present study was funded by Oryza Oil & Fat Chemical Co., Ltd. Keywords: Chrysanthemum, luteolin, uric acid, purine base

Association of perceived stress and coping strategies with the renal function in middle-aged and older Japanese men and women

Elucidating the risk factors for chronic kidney disease is important for preventing end-stage renal disease and reducing mortality. However, little is known about the roles of psychosocial stress and stress coping behaviors in deterioration of the renal function, as measured by the estimated glomerular filtration rate (eGFR). This cross-sectional study of middle-aged and older Japanese men (n = 31,703) and women (n = 38,939) investigated whether perceived stress and coping strategies (emotional expression, emotional support seeking, positive reappraisal, problem solving, and disengagement) were related to the eGFR, with mutual interactions. In multiple linear regression analyses adjusted for age, area, lifestyle factors, and psychosocial variables, we found a significant inverse association between perceived stress and the eGFR in men (Ptrend = 0.02), but not women. This male-specific inverse association was slightly attenuated after adjustment for the history of hypertension and diabetes and was more evident in lower levels of emotional expression (Pinteraction = 0.003). Unexpectedly, problem solving in men (Ptrend < 0.001) and positive reappraisal in women (Ptrend = 0.002) also showed an inverse association with the eGFR. Perceived stress may affect the eGFR, partly through the development of hypertension and diabetes. The unexpected findings regarding coping strategies require the clarification of the underlying mechanisms, including the hormonal and immunological aspects.

Sexual dysfunction associated with prostate cancer treatment in Japanese men: a qualitative research

Purpose We investigated the experiences of Japanese men with sexual dysfunction associated with various prostate cancer treatments. Methods We included 38 Japanese men who underwent the following initial treatments for prostate cancer: radical prostatectomy (n = 10), external beam radiotherapy (n = 12), brachytherapy (n = 5), and androgen deprivation therapy (n = 11). Semi-structured interviews were conducted regarding sexual dysfunction associated with prostate cancer treatment. Data were analyzed using a content analysis method. To obtain a unique experience for each treatment, we confirmed and organized the treatment method from which the code that constituted each category was derived. The category reliability was calculated based on Scott’s formula for the matching rate of the classification by three qualitative researchers. The criterion for good reliability was set at 70%. Results Japanese men with sexual dysfunction associated with prostate cancer treatments experienced the following: a desire to maintain sexual function and conflict in decision-making concerning the initial treatment for prostate cancer; a loss of values related to sexual dysfunction; an uncertainty regarding the consequences of sexual dysfunction; a sense of calm with fewer adverse effects of sexual dysfunction at the early treatment stage; an effort to accept sexual dysfunction; and management of their changed body at the later treatment stages. The concordance rates for the categories were 70% and 78%. Additionally, there were glimpses of experiences common to all treatments and trends in treatment-specific experiences. Conclusion It is necessary to provide care based on the experience of Japanese men with sexual dysfunction after prostate cancer treatment.

The Associations between Objectively Measured Physical Activity and Physical Function in Community-Dwelling Older Japanese Men and Women

Objective: The relationships between physical activity (PA) and physical function (PF) among older Japanese adults have been examined before, with some studies reporting that moderate-to-vigorous physical activity (MVPA) is positively associated with PF. However, it is unclear whether the observed associations differ between men and women. In this study, we investigated the associations of objectively measured MVPA, light physical activity (LPA), and sedentary time (ST) with different PF levels in older Japanese men and women. Subjects and Methods: A total of 810 community-dwelling subjects aged 65–75 years were investigated (52.1% women, 47.9% men). The PF variables included grip strength, one-leg standing, usual and maximum walking speeds, and chair-standing time. PA (MVPA, LPA, and ST) and the number of steps taken daily were assessed for seven consecutive days by a tri-axial accelerometer. We determined the sex-specific quartiles of MVPA, LPA, and ST and analyzed their associations with physical function in separate models for each exposure measure. Results: In the crude analysis, MVPA was significantly associated with all PF variables in the men, and with the usual walking speed, max. walking speed, and chair-standing time in the women. Neither LPA nor ST was significantly associated with any PF variables. After adjusting potential confounding factors, significant associations between MVPA and usual walking speed remained in the men and women. Conclusions: Only greater moderate-to-vigorous physical activity (MVPA) was significantly associated with higher levels of PF variables in both men and women. Thus, time spent in moderate-to-vigorous physical activity (MVPA) can help older adults maintain or improve their physical function.

Association between serum 25-hydroxyvitamin D and physical performance measures in middle-aged and old Japanese men and women: The Unzen study

Purpose Regarding epidemiological studies, the role of vitamin D in musculoskeletal functionality (muscle weakness and physical performance) among elderly people is still controversial. The purpose of the present study was to investigate the associations between 25-hydroxyvitamin D [25(OH)D] and physical performance among community-dwelling middle-aged and old Japanese men and women. Methods The subjects were community-dwelling 297 men and 415 women aged 50 years and over. Data on height (m) and weight (kg) were collected. Serum 25(OH)D, parathyroid hormone, calcium, and albumin levels were measured. Serum 25(OH)D was classified into deficiency group: < 20 ng/mL, insufficiency group: 20–30 ng/mL, and sufficiency group: ≧ 30 ng/mL. Physical performance was assessed by grip strength, chair stand time, and functional reach. Information on current smoking, alcohol drinking, regular exercise, any comorbidities (hypertension, heart disease, diabetes mellitus, lung disease, and stroke), and pain (lumbar and knee) was collected. Results Vitamin D deficiency and insufficiency based on serum 25(OH)D levels were observed in 15.2% and 56.9% of men and 52.0% and 43.6% of women, respectively. In men, higher serum 25(OH)D levels were associated with better grip strength (p for trend = 0.003), chair stand time (p for trend = 0.042), and functional reach (p for trend <0.001). On the other hand, these parameters were not associated with serum 25(OH)D levels in women. Conclusion A higher level of serum 25(OH)D was associated with better physical performance in men but not in women.