Water Intake and Adiposity Outcomes among Overweight and Obese Individuals: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Water consumption is believed to be a key factor in weight management strategies, yet the existing literature on the subject yields inconsistent findings. To systematically assess the scientific evidence regarding the effect of water intake on adiposity, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) among overweight and obese populations. METHODS: PubMed and Embase were searched for relevant articles published up to December 2023. The summary weighted mean difference (WMD) and 95% confidence interval (CI) were estimated using the DerSimonian-Laird random-effects model. RESULTS: In this meta-analysis of eight RCTs, interventions to promote water intake or to substitute water for other beverages as compared to the control group resulted in a summary WMD of -0.33 kg (95% CI = -1.75-1.08, I2 = 78%) for body weight, -0.23 kg/m2 (95% CI = -0.55-0.09, I2 = 0%) for body mass index (BMI), and 0.05 cm (95% CI = -1.20-1.30, I2 = 40%) for waist circumference (WC). Among RCTs substituting water for artificially sweetened beverages, summary WMD was 1.82 kg (95% CI = 0.97-2.67, I2 = 0%) for body weight and 1.23 cm (95% CI = -0.03-2.48, I2 = 0%) for WC. Conversely, among RCTs substituting water for sugar-sweetened beverages, summary WMD was -0.81 kg (95% CI = -1.66-0.03, I2 = 2%) for body weight and -0.96 cm (95% CI = -2.06-0.13, I2 = 0%) for WC. CONCLUSIONS: In conclusion, water intake may not significantly impact adiposity among overweight and obese individuals. However, replacing sugar-sweetened beverages with water might offer a modest benefit in inducing weight loss.

Water intake and obesity: By amount, timing, and perceived temperature of drinking water.

Water intake has been suggested to be associated with weight control, but evidence for optimal water intake in terms of amount, timing, and temperature is sparse. Additionally, genetic predisposition to obesity, which affects satiety and energy expenditure, might interact with water intake in regulating individual adiposity risk. We conducted a cross-sectional study recruiting 172 Korean adults. Information on water intake and lifestyle factors was collected through self-reported questionnaires, and height, weight, and waist circumference (WC) were measured by researchers. The oral buccal swab was performed for genotyping of FTO rs9939609, MC4R rs17782313, BDNF rs6265 and genetic risk of obesity was calculated. Linear regression was performed to estimate mean difference in body mass index (BMI) and WC by water intake and its 95% confidence interval (95% CI). As a sensitivity analysis, logistic regression was performed to estimate odds ratio (OR) of obesity/overweight (BMI of ≥23kg/m2; WC of ≥90cm for men and of ≥80cm for women) and its 95% CI. Drinking >1L/day was significantly associated with higher BMI (mean difference: 0.90, 95% CI 0.09, 1.72) and WC (mean difference: 3.01, 95% CI 0.62, 5.41) compared with drinking ≤1L/day. Independent of total water intake, drinking before bedtime was significantly associated with lower BMI (mean difference: -0.98, 95% CI -1.91, -0.05). The results remained consistent when continuous BMI and WC were analyzed as categorical outcomes. By perceived temperature, drinking >1L/day of cold water was associated with higher BMI and WC compared with drinking ≤1L/day of water at room-temperature. By genetic predisposition to obesity, a positive association between water intake and WC was confined to participants with low genetic risk of obesity (P interaction = 0.04). In conclusion, amount, timing, and perceived temperature of water intake may be associated with adiposity risk and the associations might vary according to genetic predisposition to obesity.

Association between weight cycling and risk of colorectal cancer: a prospective cohort study.

BACKGROUND: Weight cycling is the repeated episodes manifesting intentional weight loss and subsequent unintentional weight gain. Whether the frequency and magnitude of weight cycling is associated with colorectal cancer risk independent of body mass index (BMI) remains unknown. METHODS: Two prospective cohort studies, Nurses' Health Study I and Health Professionals Follow-up Study, followed 85,562 participants from 1992 to 2014. Participants completed a questionnaire regarding the frequency and magnitude of intentional weight loss in the past 4 years at the baseline. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard model. RESULTS: We identified 1626 colorectal cancer cases during up to 22 years of follow-up. In the pooled analysis of HPFS and NHS, compared to non-weight cycling, moderate weight cycling (≥3 times of intentional weight loss of ≥2.3-4.4 kg) was associated with a reduced risk of colorectal cancer after adjustment for confounders, including attained BMI after weight cycling (HR = 0.82, 95% CI 0.69, 0.97). However, no significant association was observed in mild weight cyclers and in severe weight cyclers. CONCLUSIONS: Moderate weight cycling was associated with a lower risk of colorectal cancer independent of BMI. This finding needs further studies for replication and putative biological mechanisms.

AHR rs4410790 genotype and IgG levels: Effect modification by lifestyle factors.

Inflammation is a multifaceted marker resulting from complex interactions between genetic and lifestyle factors. Emerging evidence suggests Aryl hydrocarbon receptor (AHR) protein may be implicated in the regulation of immune system and inflammatory responses. To investigate whether rs4410790 genotype (TT, TC, CC) near AHR gene is related to serum IgG levels, a marker of chronic inflammation, and whether lifestyle factors modifies the relationship, we conducted a cross-sectional study by recruiting 168 Korean adults. Participants responded to a lifestyle questionnaire and provided oral epithelial cells and blood samples for biomarker assessment. Among these participants, C allele was the minor allele, with the minor allele frequency of 40%. The rs4410790 TT genotype was significantly associated with elevated IgG levels compared with TC/CC genotypes, after adjusting for potential confounders (p = 0.04). The relationship varied significantly by levels of alcohol consumption (P interaction = 0.046) and overweight/obese status (P interaction = 0.02), but not by smoking status (P interaction = 0.64) and coffee consumption (P interaction = 0.55). Specifically, higher IgG levels associated with the TT genotype were evident in frequent drinkers and individuals with BMI≥23kg/m2, but not in their counterparts. Thus, rs4410790 genotype may be associated with IgG levels and the genetic predisposition to higher IgG levels may be mitigated by healthy lifestyle factors like infrequent drinking and healthy weight.

Plasma total cholesterol concentration and risk of higher-grade prostate cancer: A nested case-control study and a dose-response meta-analysis.

Our previous publication found an increased risk of higher-grade (Gleason sum ≥7) prostate cancer for men with high total cholesterol concentration (≥200 mg/dl) in the Health Professionals Follow-up Study (HPFS). With additional 568 prostate cancer cases, we are now able to investigate this association in more detail. For the nested case-control study, we included 1260 men newly diagnosed with prostate cancer between 1993 and 2004, and 1328 controls. For the meta-analyses, 23 articles studied the relationship between total cholesterol level and prostate cancer incidence were included. Logistic regression models and dose-response meta-analysis were performed. An increased risk of higher-grade (Gleason sum ≥4 + 3) prostate cancer for high vs low quartile of total cholesterol level was observed in the HPFS (ORmultivariable = 1.56; 95% CI = 1.01-2.40). This finding was compatible with the association noted in the meta-analysis of highest vs lowest group of total cholesterol level, which suggested a moderately increased risk of higher-grade prostate cancer (Pooled RR =1.21; 95%CI: 1.11-1.32). Moreover, the dose-response meta-analysis indicated that an increased risk of higher-grade prostate cancer occurred primarily at total cholesterol levels ≥200 mg/dl, where the RR was 1.04 (95%CI: 1.01-1.08) per 20 mg/dl increase in total cholesterol level. However, total cholesterol concentration was not associated with the risk of prostate cancer overall either in the HPFS or in the meta-analysis. Our primary finding, as well as the result of the meta-analysis suggested a modest increased risk of higher-grade prostate cancer, at total cholesterol concentrations exceeding 200 mg/dl.

Changes in total cholesterol level and cardiovascular disease risk among type 2 diabetes patients.

Despite many diabetic patients having hypercholesterolemia, the association of total cholesterol (TC) levels with CVD risk in type 2 diabetes (T2D) patients is unclear. Diagnosis of type 2 diabetes often leads to changes in total cholesterol (TC) levels. Thus, we examined whether changes in TC levels from pre- to post-diagnosis of T2D were associated with CVD risk. From the National Health Insurance Service Cohort, 23,821 individuals diagnosed with T2D from 2003 to 2012 were followed-up for non-fatal CVD incidence through 2015. Two measurements of TC, 2 years before and after T2D diagnosis, were classified into 3 levels (low, middle, high) to define changes in cholesterol levels. Cox proportional hazards regression was performed to estimate adjusted hazards ratios (aHRs) and 95% confidence intervals (CIs) for the associations between changes in cholesterol levels and CVD risk. Subgroup analyses were performed by use of lipid-lowering drugs. Compared with low-low, aHR of CVD was 1.31 [1.10-1.56] for low-middle and 1.80 [1.15-2.83] for low-high. Compared with middle-middle, aHR of CVD was 1.10 [0.92-1.31] for middle-high but 0.83 [0.73-0.94] for middle-low. Compared with high-high, aHR of CVD was 0.68 [0.56-0.83] for high-middle and 0.65 [0.49-0.86] for high-low. The associations were observed regardless of use of lipid-lowering drugs. For diabetic patients, management of TC levels may be important to lower CVD risk.

Plant-based dietary patterns and the risk of digestive system cancers in 3 large prospective cohort studies.

Little is known about the relation between plant-based dietary patterns and digestive system cancers. This study investigated the prospective association between 3 pre-defined indices of plant-based dietary pattern and risk of digestive system cancers, as a whole or individually. We utilized data from 3 prospective cohorts, the Nurses' Health Study (1984-2018, 74,496 women aged 65 ± 10.9 years), Nurses' Health Study II (1991-2017, 91,705 women aged 49.3 ± 8.3 years), and Health Professionals Follow up Study (1986-2016, 45,472 men aged 65.4 ± 11.0 years). We used Cox proportional hazards regression models to estimate multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) of digestive system cancers across 3 plant-based diet index scores: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI). During a follow-up of 4,914,985 person-years, we identified 6,518 cases of digestive system cancers. In the pooled analysis of 3 cohorts, the HRs (95% CIs) per 10-point increase in hPDI score were 0.93 (0.89, 0.97) for total digestive system cancer, 0.94 (0.89, 0.99) for gastrointestinal tract cancer, 0.89 (0.81, 0.98) for accessory organ cancer, and 0.68 (0.52, 0.91) for liver cancer. In contrast, the HRs (95% CIs) per 10-point increase in uPDI score was 1.06 (1.01, 1.11) for gastrointestinal tract cancer and 1.07 (1.01, 1.13) for colorectal cancer. A healthy plant-based dietary pattern was associated with reduced risks of total digestive system cancers as well as individual cancers in the gastrointestinal tract and the accessory organs. Emphasizing the healthiness and quality of plant-based diets may be important for the prevention of developing cancers in the digestive system.

Long-term Weight Training and Mortality in U.S. Male Health Professionals With and Without Type 2 Diabetes.

OBJECTIVE: To investigate the relationship between long-term weight training and mortality in male health professionals with and without type 2 diabetes. RESEARCH DESIGN AND METHODS: We analyzed 31,140 men without type 2 diabetes and 2,588 with type 2 diabetes from the Health Professionals Follow-up Study (1992-2018). Information on weight training was repeatedly assessed using a biennial questionnaire. Cox regression was used to estimate hazard ratios (HRs) and 95% CIs. RESULTS: During up to 26 years of follow-up, we documented 12,607 deaths (988 deaths among men with type 2 diabetes). Among participants without type 2 diabetes, 1-59 and 60-149 min/week of long-term weight training were associated with 14% (HR 0.86; 95% CI 0.82-0.89) and 8% (HR 0.92; 95% CI 0.85-0.99) lower mortality versus no weight training, respectively, after adjustment for aerobic activity. However, ≥150 min/week of weight training was not significantly associated with mortality (HR 1.05; 95% CI 0.91-1.20; overall P trend = 0.94; P quadratic < 0.001). Meeting the recommended aerobic physical activity guideline (≥150 min/week) and performing any weight training were associated with 20-34% lower mortality. Among participants with type 2 diabetes, a moderate level of pre-diagnosis weight training was associated with lower mortality, whereas post-diagnosis weight training showed no association. Performing both weight training and aerobic activity before and after diagnosis was associated with lower mortality. CONCLUSIONS: A moderate level of long-term weight training was associated with lower mortality, independently of aerobic activity, among male health professionals with and without type 2 diabetes. Addition of weight training to aerobic activities may provide further benefit in mortality risk reduction. Studies are required to confirm our findings in diverse populations.

The Effects of Mindfulness and Buddhist Meditation Coaching on Mental Health Outcomes in College Students.

College students are vulnerable to diverse mental health disorders. We aimed to investigate whether a meditation class would be an effective means to address students' mental health challenges. Among the college students who registered for the meditation course, 256 participants were enrolled. The meditation course was a 15-week program incorporating mindfulness meditation and Ganhwa Seon (a traditional Buddhist meditation). A questionnaire was administered twice, on the first and last class of the course, collecting information on personal characteristics and six mental health indicators. A paired t-test was used to examine whether the meditation course conferred benefit on the mental health indicators, and logistic regression analyses were run to identify factors associated with mental health outcomes. After completing the meditation course, there were significant improvements for the adult ADHD score (p < 0.01) and ego identity (p = 0.02) but not for the other outcomes. Among college students, meditation practice may have positive effects on the adult ADHD score and ego identity.

Temporal Association of Total Serum Cholesterol and Pancreatic Cancer Incidence.

Previous studies have suggested a "cholesterol-lowering effect" of preclinical pancreatic cancer, suggesting lower total cholesterol as a potential diagnostic marker. Leveraging repeated measurements of total cholesterol, this study aims to examine the temporal association of total cholesterol and pancreatic cancer incidence. We conducted a nested case-control study based on a Korean National Health Insurance Service−Health Screening Cohort, including 215 pancreatic cancer cases and 645 controls matched on age and sex. Conditional logistic regression was applied to estimate the odds ratio (OR) and 95% confidence interval (CI) for the associations of pancreatic cancer incidence with total cholesterol levels across different time windows over 11 years before pancreatic cancer diagnosis (recent, mid, distant). We found that, compared to participants with total cholesterol < 200 mg/dL in the recent 3 years prior to diagnosis, those having total cholesterol ≥ 240 mg/dL showed a significantly lower pancreatic cancer incidence (OR = 0.50 (0.27−0.93)). No significant association was found in relation to total cholesterol measured in the mid and distant past. When changes in total cholesterol over the three time periods were analyzed, compared with those with total cholesterol levels consistently below 240 mg/dL over the entire period, the OR of pancreatic cancer was 0.45 (0.20−1.03) for participants with recent-onset hypercholesterolemia, 1.89 (0.95−3.75) for recent-resolved hypercholesterolemia, and 0.71 (0.30−1.66) for consistent hypercholesterolemia. In conclusion, while high total cholesterol in the recent past may indicate a lower pancreatic cancer incidence, a recent decrease in total cholesterol may suggest an elevated incidence of pancreatic cancer.

Post-Diagnosis Vitamin D Supplement Use and Survival among Cancer Patients: A Meta-Analysis.

Vitamin D administered pre-diagnostically has been shown to reduce mortality. Emerging evidence suggests a role of post-diagnosis vitamin D supplement intake for survival among cancer patients. Thus, we conducted a meta-analysis to evaluate the relationship. PubMed and Embase were searched for relevant observational cohort studies and randomized trials published through April 2022. Summary relative risk (SRR) and 95% confidence interval (CI) were estimated using the DerSimonian-Laird random-effects model. The SRR for post-diagnosis vitamin D supplement use vs. non-use, pooling cohort studies and randomized trials, was 0.87 (95% CI, 0.78-0.98; p = 0.02; I2 = 0%) for overall survival, 0.81 (95% CI, 0.62-1.06; p = 0.12; I2 = 51%) for progression-free survival, 0.86 (95% CI, 0.72-1.03; p = 0.10; I2 = 0%) for cancer-specific survival, and 0.86 (95% CI, 0.64-1.14; p = 0.29; I2 = 0%) for relapse. Albeit not significantly heterogeneous by variables tested, a significant inverse association was limited to cohort studies and supplement use during cancer treatment for overall survival, and to studies with ≤3 years of follow-up for progression-free survival. Post-diagnosis vitamin D supplement use was associated with improved overall survival, but not progression-free or cancer-specific survival or relapse. Our findings require confirmation, as randomized trial evidence was insufficient to establish cause-and-effect relationships.

Long-Term Leisure-Time Physical Activity Intensity and All-Cause and Cause-Specific Mortality: A Prospective Cohort of US Adults.

BACKGROUND: The 2018 physical activity guidelines for Americans recommend a minimum of 150 to 300 min/wk of moderate physical activity (MPA), 75 to 150 min/wk of vigorous physical activity (VPA), or an equivalent combination of both. However, it remains unclear whether higher levels of long-term VPA and MPA are, independently and jointly, associated with lower mortality. METHODS: A total of 116 221 adults from 2 large prospective US cohorts (Nurses' Health Study and Health Professionals Follow-up Study, 1988-2018) were analyzed. Detailed self-reported leisure-time physical activity was assessed with a validated questionnaire, repeated up to 15 times during the follow-up. Cox regression was used to estimate the hazard ratio and 95% CI of the association between long-term leisure-time physical activity intensity and all-cause and cause-specific mortality. RESULTS: During 30 years of follow-up, we identified 47 596 deaths. In analyses mutually adjusted for MPA and VPA, hazard ratios comparing individuals meeting the long-term leisure-time VPA guideline (75-149 min/wk) versus no VPA were 0.81 (95% CI, 0.76-0.87) for all-cause mortality, 0.69 (95% CI, 0.60-0.78) for cardiovascular disease (CVD) mortality, and 0.85 (95% CI, 0.79-0.92) for non-CVD mortality. Meeting the long-term leisure-time MPA guideline (150-299 min/wk) was similarly associated with lower mortality: 19% to 25% lower risk of all-cause, CVD, and non-CVD mortality. Compared with those meeting the long-term leisure-time physical activity guidelines, participants who reported 2 to 4 times above the recommended minimum of long-term leisure-time VPA (150-299 min/wk) or MPA (300-599 min/wk) showed 2% to 4% and 3% to 13% lower mortality, respectively. Higher levels of either long-term leisure-time VPA (≥300 min/wk) or MPA (≥600 min/wk) did not clearly show further lower all-cause, CVD, and non-CVD mortality or harm. In joint analyses, for individuals who reported <300 min/wk of long-term leisure-time MPA, additional leisure-time VPA was associated with lower mortality; however, among those who reported ≥300 min/wk of long-term leisure-time MPA, additional leisure-time VPA did not appear to be associated with lower mortality beyond MPA. CONCLUSIONS: The nearly maximum association with lower mortality was achieved by performing ≈150 to 300 min/wk of long-term leisure-time VPA, 300 to 600 min/wk of long-term leisure-time MPA, or an equivalent combination of both.

Milk Intake in Early Life and Later Cancer Risk: A Meta-Analysis.

Dairy consumption in adulthood has been demonstrated to influence cancer risk. Although childhood and adolescence represent critical periods of rapid growth, the relationship between milk intake in early life and later cancer risk is unclear. Thus, we examined this relationship by conducting a meta-analysis of the observational studies. PubMed and Embase were searched for relevant articles that were published throughout December 2021. The summary relative risk (RR) and 95% confidence interval (CI) were estimated using the DerSimonian-Laird random-effects model. The summary RR for the highest vs. lowest milk intake was 0.83 (95% CI = 0.69-1.00; p = 0.05; I2 = 60%; seven studies) for breast cancer, 0.98 (95% CI = 0.72-1.32; p = 0.88; I2 = 51%; four studies) for prostate cancer, and 0.90 (95% CI = 0.42-1.93; p = 0.78; I2 = 83%; three studies) for colorectal cancer. No evidence of an association emerged in subgroup analyses of menopausal status, cancer stage, fat content of milk, life stage of milk intake, or study design. Consistent results were observed in the meta-analyses using total dairy intake. In conclusion, milk intake during childhood and adolescence might not be associated with risks of breast, prostate, and colorectal cancer later in life. Given the small number of studies that were included in our meta-analysis, and the high heterogeneity, more studies are warranted for a definitive conclusion.

Early-life body mass index and risks of breast, endometrial, and ovarian cancers: a dose-response meta-analysis of prospective studies.

BACKGROUND: The evidence for the associations between early-life adiposity and female cancer risks is mixed. Little is known about the exact shape of the relationships and whether the associations are independent of adult adiposity. METHODS: We conducted dose-response meta-analyses of prospective studies to summarise the relationships of early-life body mass index (BMI) with breast, endometrial, and ovarian cancer risks. Pubmed and Embase were searched through June 2020 to identify relevant studies. Using random-effects models, the summary relative risks (RRs) and 95% confidence intervals (CIs) were estimated per 5-kg/m2 increase in BMI at ages ≤ 25 years. A nonlinear dose-response meta-analysis was conducted using restricted cubic spline analysis. RESULTS: After screening 33,948 publications, 37 prospective studies were included in this analysis. The summary RRs associated with every 5-kg/m2 increase in early-life BMI were 0.84 (95% CI = 0.81-0.87) for breast, 1.40 (95% CI = 1.25-1.57) for endometrial, and 1.15 (95% CI = 1.07-1.23) for ovarian cancers. For breast cancer, the association remained statistically significant after adjustment for adult BMI (RR = 0.80, 95% CI = 0.73-0.87). For premenopausal breast, endometrial, and ovarian cancers, the dose-response curves suggested evidence of nonlinearity. CONCLUSIONS: With early-life adiposity, our data support an inverse association with breast cancer and positive associations with ovarian and endometrial cancer risks.

Association between weight cycling and risk of kidney cancer: a prospective cohort study and meta-analysis of observational studies.

PURPOSE: Weight cycling is common in populations. However, it is unclear whether frequency and magnitude of weight cycling is associated with kidney cancer risk, independent of body mass index (BMI). METHODS: A prospective cohort study followed 85,562 participants from Health Professionals Follow-up Study and Nurses' Health Study (1992-2014). At baseline, participants reported frequency and magnitude of intentional weight loss in the past 4 years. Cox proportional hazard model was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). We also conducted a meta-analysis of all available observational studies including our two cohorts. RESULTS: During 22 years of follow-up, we identified 441 kidney cancer cases. Compared with non-weight cyclers (no attempt of intentional weight loss), severe cyclers (≥ 3 times of intentional weight loss of ≥ 4.5 kg) were at increased kidney cancer risk after adjusting for BMI before weight cycling (pooled multivariable-adjusted HR, 1.78; 95% CI, 1.19, 2.66). Additional adjustment for attained BMI after weight cycling had minimal influence. There was a positive trend between weight cycling by frequency and magnitude and kidney cancer risk (P-trend = 0.01). Moreover, the observed positive association did not differ by subtypes of cyclers (e.g., adiposity status, weight-loss methods). In the meta-analysis, we found a strong positive association between weight cycling and kidney cancer risk (summary relative risk for weight cyclers vs. non-cyclers, 1.51; 95% CI, 1.16, 1.96; I2: 52.2%; 6 studies). CONCLUSION: Frequent substantial weight cycling was associated with increased risk of kidney cancer, independent of BMI. Our study suggests that weight cycling may be an important risk factor for kidney cancer.

Physical activity and all-cause and cause-specific mortality: assessing the impact of reverse causation and measurement error in two large prospective cohorts.

Most cohort studies have only a single physical activity (PA) measure and are thus susceptible to reverse causation and measurement error. Few studies have examined the impact of these potential biases on the association between PA and mortality. A total of 133,819 participants from Nurses' Health Study and Health Professionals Follow-up Study (1986-2014) reported PA through biennial questionnaires. Cox regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for PA and mortality using different analytic approaches comparing single (baseline, simple update = most recent) versus repeated (cumulative average) measures of PA and applying various lag times separating PA measurement and time at risk. Over 3.2 million person-years, we documented 47,273 deaths. The pooled multivariable-adjusted HR (95% CI) of all-cause mortality per 10 MET-hour/week was 0.95 (0.94-0.96) for baseline PA, 0.78 (0.77-0.79) for simple updated PA and 0.87 (0.86-0.88) for cumulative average PA in the range of 0-50 MET-hour/week. Simple updated PA showed the strongest inverse association, suggesting larger impact of reverse causation. Application of 2-year lag substantially reduced the apparent reverse causation (0.85 (0.84-0.86) for simple updated PA and 0.90 (0.89-0.91) for cumulative average PA), and 4-12-year lags had minimal additional effects. In the dose-response analysis, baseline or simple updated PA showed a J or U-shaped association with all-cause mortality while cumulative average PA showed an inverse association across a wide range of PA (0-150 MET-hour/week). Similar findings were observed for different specific mortality causes. In conclusion, PA measured at baseline or with short lag time was prone to bias. Cumulative average PA showed robust evidence that PA is inversely associated with mortality in a dose-response manner.

Time trends of colorectal cancer incidence and associated lifestyle factors in South Korea.

Worldwide, South Korea had the second highest incidence rates of colorectal cancer (CRC) in 2018. To inform public health policy to prevent CRC, we aimed to identify major modifiable lifestyle factors underlying the alarming increase in CRC incidence. We obtained information on CRC statistics from the Korea National Cancer Incidence Database and on the distribution of dietary and lifestyle factors known to modify CRC risk from the Korea National Health and Nutrition Examination Survey. To examine time trends between 2001 and 2013, we calculated annual percent changes of CRC incidence rates and of prevalence of etiologic factors by sex and age. Across all sex and age groups, the most commonly diagnosed cancer was rectal cancer while the most rapidly increasing cancer was distal colon cancer. For the lifestyle factors examined, decreases in exercise were observed across all age groups of both sexes. Yet, obesity and alcoholic drinks appear more relevant CRC contributor to men, smoking to women aged 30-49 years, and processed meat intake to adults aged 30-49 years. The heterogeneous results suggest that dietary and lifestyle target to prevent CRC be tailored by sex and age.

Adiposity and mortality in Korean adults: a population-based prospective cohort study.

BACKGROUND: The Asia-Pacific obesity classification recommends using lower BMI cutoffs in Asians compared with those in Western populations. However, the supporting evidence is scarce and little is known about the exact shape of the relations between adiposity and mortality in Asians. OBJECTIVES: We investigated the relations of BMI (in kg/m2), waist circumference, and predicted body fat mass with mortality using a population-based prospective cohort of Korean men and women. METHODS: This analysis included 44,060 Korea National Health and Nutrition Examination Survey 2007-2014 participants who agreed to mortality follow-up through 31 December, 2016. At baseline, height, weight, and waist circumference were measured. Using DXA data, we derived predicted body fat and fat-free mass. Cox proportional hazards models were used to estimate HRs and 95% CIs for the associations with mortality, adjusting for potential confounders. We tested for nonlinearity using the likelihood ratio test comparing nonlinear restricted cubic spline models with linear models. RESULTS: During ≤9.5 y of follow-up, 1682 deaths were identified. The relations of BMI with all-cause and cardiovascular mortality were J-shaped with the nadir at BMI = 25.0-29.9 (P-nonlinearity < 0.001). Among participants without a history of cancer or cardiovascular disease, waist circumference (≥95 compared with 75.0-79.9 cm: HR: 2.10; 95% CI: 1.54, 2.86) and predicted body fat mass (highest compared with lowest sextiles: 2.55; 95% CI: 1.60, 4.06) were positively associated with all-cause mortality (all P-nonlinearity ≤ 0.03), as well as cancer and cardiovascular mortality. The highest mortality was observed among participants who had both high predicted fat mass and low fat-free mass. CONCLUSIONS: Our data suggest a strong positive association between adiposity and mortality in a population without pre-existing disease. We observed the lowest mortality at BMI = 25.0-29.9, suggesting that the current cutoff for overweight (BMI ≥23) may require re-evaluation and that BMI alone may not be a useful measure for indicating adiposity in Asians.

Alcohol Consumption and the Risk of Prostate Cancer: A Dose-Response Meta-Analysis.

Alcohol is widely consumed and is known as a major risk factor for several types of cancers. Yet, it is unclear whether alcohol consumption is associated with the risk of prostate cancer (PCa) or not. We conducted linear and non-linear dose-response meta-analyses of cohort studies on alcohol consumption and PCa risk by types of alcohol (total, wine, beer, and liquor) and PCa (non-aggressive and aggressive). Pubmed and Embase were searched through April 2020 to identify relevant studies. Summary relative risk (RR) and 95% confidence interval (CI) were estimated using a random-effects model. For non-aggressive PCa, by alcohol type, the risk increased linearly with liquor (RR per 14 g/day intake (alcohol content in standard drink) being 1.04 (95% CI = 1.02-1.06, I2 = 0%, three studies) and non-linearly with beer (Pnon-linearity = 0.045, four studies), with increased risk observed in the lower range (RR = 1.03, 95% CI = 1.01-1.05; 14 g/day), with 1.05 (95% CI = 1.01-1.08) at 28 g/day. Wine was not significantly associated with the risk of non-aggressive PCa. For aggressive PCa, a non-linear relationship of diverse shapes was indicated for all types of alcohol in the sensitivity analysis. Compared to non-drinking, a significant positive association was more apparent at lower dose for liquor (RR = 1.12, 95% CI = 1.04-1.20 at 14 g/day; RR = 1.16, 95% CI = 1.03-1.31 at 28 g/day; Pnon-linearity = 0.005, three studies) but at higher doses for wine (RR = 1.02, 95% CI = 0.90-1.16 at 28 g/day, RR = 1.35, 95% CI = 1.08-1.67 at 56 g/day; Pnon-linearity = 0.01, four studies). In contrast, decreased risks were indicated at lower doses of beer (RR = 0.85, 95% CI = 0.79-0.92 at 14 g/day; RR = 0.79, 95% CI = 0.70-0.90 at 28 g/day, Pnon-linearity < 0.001, four studies). Total alcohol consumption was not associated with both types of PCa. In this study, we found heterogeneous associations between alcohol intake and PCa by types of alcohol and PCa.

Lifestyle risk score and mortality in Korean adults: a population-based cohort study.

Individual lifestyle risk factors have been associated with an increased risk of mortality. However, limited evidence is available on the combined association of lifestyle risk factors with mortality in non-Western populations. The analysis included 37,472 participants (aged ≥19 years) in the Korea National Health and Nutrition Examination Surveys (2007-2014) for whom the data were linked to death certificates/medical records through December 2016. A lifestyle risk score was created using five unhealthy behaviors: current smoking, high-risk alcohol drinking, unhealthy weight, physical inactivity, and insufficient/prolonged sleep. Cox proportional hazards models were used to estimate hazard ratio (HR) and 95% confidence interval (CI). During up to 9 years of follow-up, we documented 1,057 total deaths. Compared to individuals with zero lifestyle risk factor, those with 4-5 lifestyle risk factors had 2.01 times (HR = 2.01, 95% CI = 1.43-2.82) and 2.59 times (HR = 2.59, 95% CI = 1.24-5.40) higher risk of all-cause and cardiovascular mortality, respectively. However, higher lifestyle risk score was not significantly associated with cancer mortality (p-trend >0.05). In stratified analyses, the positive associations tended to be stronger in adults aged <65 years, unemployed, and those with lower levels of education. In conclusion, combined unhealthy lifestyle behaviors were associated with substantially increased risk of total and cardiovascular mortality in Korean adults.