Metabolic syndrome associated with habitual indulgence and dietary behavior in middle-aged health-care professionals

Smoking cessation and risk of metabolic syndrome: A meta-analysis

BACKGROUND

Smoking is an important risk factor for various metabolic and cardiovascular disorders, and smoking cessation reduces the risk of these conditions. However, weight gain is commonly observed when individuals quit smoking, which often leads to hesitation in pursuing smoking cessation. Weight gain increases the risk of metabolic syndrome (MS). However, previous studies that investigated the relationship between smoking cessation and MS have yielded inconsistent results. Therefore, we conducted a meta-analysis to evaluate the association between smoking cessation and MS.

METHODS

Medline, Embase, Cochrane Library and CINAHL databases, were comprehensively searched from inception to April 2023, to identify relevant studies examining the relationship between smoking cessation and MS, comparing such relationship to that with active smoking. The methodological quality of the selected studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. A random-effects model was used for meta-analysis.

RESULTS

Of 495 identified studies, 24 were reviewed. The risk of selection bias was identified in all the studies. The overall analysis of 14 studies, including data of combined results for both men and women, revealed an increased risk of MS among ex-smokers compared with that among active smokers (pooled relative risk [RR] 1.18, 95% confidence interval [CI]: 1.08-1.29). From the selected studies, 13 studies analyzing men were extracted for subgroup analysis. Among men, no significant difference in the risk of developing MS was observed between ex-smokers and smokers (pooled RR: 1.05, 95% CI: 0.95-1.17). In men, the risk of MS increased if the cessation period was ≤15 years in men (pooled RR 1.26, 95% CI: 1.01-1.56) and slightly decreased if the cessation period was > 15 years (RR 0.84, 95% CI: 0.70-1.00) in ex-smokers compared with that in current smokers.

CONCLUSION

An increased risk of MS was observed in the early stages of smoking cessation compared with current smoking. As the longer duration of smoking cessation, the risk of MS becomes less significant.

Effect of Coffee and Tea Consumption on Adolescent Weight Control: An Interventional Pilot Study

Background: Both catechin polyphenols and caffeine have been shown to have beneficial effects on weight control in the adult population. However, the influence of tea or coffee supplementation on body weight in adolescents has never been tested. The aim of the present study was to investigate the effect of tea and coffee consumption on body weight and body fat in adolescents with obesity. Methods: Randomized clinical trial comparing three weight-loss interventions composed of similar family-based counseling sessions on nutritional education with coffee (2 cups per day, total amount 160 mg caffeine), green tea (3 cups per day, total amount 252 mg catechin and 96 mg caffeine), or herbal tea (as placebo, 3 cups per day). Nutritional intake, BMI, and fat percentage, as measured by bioelectrical impedance, were compared between the groups at 3 and 6 months. Results: Forty-eight children were included in the final analysis: 18 in the coffee arm, 17 in the green tea arm, and 13 in the placebo arm. Nineteen (39.6%) children were males, with a median (interquartile range) age of 13 (11-14) years. There were no significant group differences in age, sex, and BMI (absolute number and percent of the 95th percentile) upon study entry. Comparison between the three interventions in total change in BMI from baseline revealed a significant advantage for coffee consumption compared with green tea and placebo (-9.2% change in BMI in the coffee group compared with -2.3% and 0.76% in the green tea and placebo group, respectively, p = 0.002). Conclusions: Dietary recommendations combined with coffee intake and, to a lesser extent, tea catechins may be associated with reduced weight and adiposity among adolescents. Clinical trial registration number: NCT05181176.

Relationship between Coffee, Tea, and Carbonated Beverages and Cardiovascular Risk Factors

We aimed to analyze the relationship between coffee, tea, and carbonated beverages and cardiovascular risk factors. We used data from the fourth to eighth Korea National Health and Nutrition Examination Surveys (2007-2016, 2019-2020). We categorized the frequency of intake into three groups (<1 time/week, 1 time/week to <1 time/day, and ≥1 time/day). Subsequently, logistic regression analyses by sex were performed to assess cardiovascular risk factors (hypertension (HTN), diabetes mellitus (DM), dyslipidemia (DL), or metabolic syndrome (MetS)) according to the frequency of coffee, tea, and carbonated beverage intake. For HTN, coffee intake showed an inverse relationship and tea intake showed a direct relationship. For DM, coffee intake showed an inverse relationship, and tea and carbonated beverage intake showed a direct relationship. For DL, coffee intake showed an inverse relationship, whereas tea intake demonstrated a direct relationship. In addition, carbonated beverage intake showed a direct relationship with MetS. Coffee intake showed an inverse relationship with HTN, DM, and DL. However, tea intake showed a direct relationship with HTN, DM, and DL, whereas carbonated beverage intake showed a direct relationship with DM and MetS.

The Relationship between Habitual Coffee Drinking and the Prevalence of Metabolic Syndrome in Taiwanese Adults: Evidence from the Taiwan Biobank Database

Previous studies revealed inconsistent results between coffee drinking and metabolic syndrome (MetS). The aim of the study was to evaluate the relationship between habitual coffee drinking and the prevalence of MetS among men and women. We conducted a nationwide, cross-sectional study using 23,073 adults obtained from the Taiwan Biobank database (mean ± SD (range) age, 54.57 ± 0.07 (30–79) years; 8341 men and 14,731 (63.8%) women). Adults who drank more than one cup of coffee per day (n = 5118) and those who drank less than one cup per day (n = 4515) were compared with nondrinkers (n = 13,439). Multivariate logistic regression models were used to evaluate the risk of MetS between the two groups. Separate models were also estimated for sex-stratified and habitual coffee-type-stratified (black coffee (BC), coffee with creamer (CC), and coffee with milk (CM)) subgroup analyses. The MetS diagnosis was based on at least three of the five metabolic abnormalities. Coffee drinkers (≥1 cup/day) had a significantly lower prevalence of MetS than nondrinkers (AOR (95% CI): 0.80 (0.73–0.87)). Women who drank any amount of coffee and any type of coffee were more likely to have a significantly lower prevalence of MetS than nondrinkers. Only men who drank more than one cup of coffee per day or black coffee drinkers were more likely to have a lower prevalence of MetS. Our study results indicate that adults with habitual coffee drinking behaviors of more than one cup per day were associated with a lower prevalence of MetS. Moreover, women could benefit from habitual coffee drinking of all three coffee types, whereas men could only benefit from drinking BC.

The Association Between Coffee Consumption and Metabolic Syndrome in Adults: A Systematic Review and Meta-Analysis

Previous meta-analyses that found an inverse association between coffee consumption and metabolic syndrome pooled data from cross-sectional and longitudinal studies, which could lead to potentially misleading conclusions. Hence, this work aimed to reassess this association by analyzing data from the 2 types of studies separately and including recent studies. Online databases including PubMed, Scopus, Embase, The Cumulative Index to Nursing and Allied Health Literature (CINAHL) Plus, and Science Direct were searched for relevant studies published up to July 2020. Both cross-sectional and longitudinal studies were included if published after 1999, reported both effect estimates and CIs, and presented results adjusted for confounding variables. Data of the highest coffee consumption level in each study, as well as those of medium consumption levels in studies with ≥3 consumption categories, were pooled using random-effect models, with sex-stratified and sex-adjusted results being analyzed separately. Results were obtained based on data from 13 cross-sectional studies involving 280,803 participants and 2 longitudinal studies involving 17,014 participants. The overall sex-adjusted association of the highest consumption level was not significant (n = 9 studies; OR: 0.88; 95% CI: 0.70, 1.10; I2: 91.5%) and the 2 longitudinal studies both yielded no association. Subgroup analysis revealed inverse associations in both males and females, as well as in Caucasians with medium coffee consumption (n = 4 studies, OR: 0.88; 95% CI: 0.84, 0.93; I2: 0%). Although residual confounding could affect the results of this meta-analysis, our findings suggested with a low certainty that coffee consumption may not be associated with metabolic syndrome, a finding that is different from those of previous meta-analyses and could be due to variation in characteristics of study participants. More longitudinal studies are also needed to further assess the temporal association between coffee consumption and metabolic syndrome. This meta-analysis was registered at https://www.crd.york.ac.uk/prospero as CRD42018110650.

How coffee affects metabolic syndrome and its components

Metabolic syndrome, with its increasing prevalence, is becoming a major public health problem throughout the world. Many risk factors including nutrition play a role in the emergence of metabolic syndrome. Of the most-consumed beverages in the world, coffee contains more than 1000 components such as caffeine, chlorogenic acid, diterpenes and trigonelline. It has been proven in many studies that coffee consumption has a positive effect on chronic diseases. In this review, starting from the beneficial effects of coffee on health, the relationship between coffee consumption and metabolic syndrome and its components has been investigated. There are few studies investigating the relationship between coffee and metabolic syndrome, and the existing ones put forward different findings. The factors leading to the differences are thought to stem from coffee variety, the physiological effects of coffee elements, and the nutritional ingredients (such as milk and sugar) added to coffee. It is reported that consumption of coffee in adults up to three cups a day reduces the risk of Type-2 diabetes and metabolic syndrome.

Coffee and tea consumption in relation with non-alcoholic fatty liver and metabolic syndrome: A systematic review and meta-analysis of observational studies

BACKGROUND & AIMS

Diet plays a role in the onset and progression of metabolic disorders, including non-alcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS). We aimed to systematically review and perform quantitative analyses of results from observational studies on coffee/tea consumption and NAFLD or MetS.

METHODS

A Medline and Embase search was performed to retrieve articles published up to March 2015. We used a combination of the keywords "coffee", "caffeine", "tea", "non-alcoholic fatty liver disease", "non-alcoholic steatohepatitis", "metabolic syndrome". Pooled risk ratios (RRs) and 95% confidence intervals (CIs) were calculated by random-effects model.

RESULTS

Seven studies assessed coffee consumption in NAFLD patients. Fibrosis scores were reported in four out of seven; all four studies revealed an inverse association of coffee intake with fibrosis severity, although the lack of comparable exposure and outcomes did not allow to perform pooled analysis. Seven studies met the inclusion criteria to be included in the meta-analysis on coffee consumption and MetS. Individuals consuming higher quantities of coffee were less like to have MetS (RR = 0.87, 95% CI: 0.79-0.96). However, the association of coffee and individual components of MetS was not consistent across the studies. Pooled analysis of six studies exploring the association between tea consumption and MetS resulted in decreased odds of MetS for individuals consuming more tea (RR = 0.83, 95% CI: 0.73-0.95).

CONCLUSIONS

Studies on coffee and NAFLD suggest that coffee consumption could have a protective role on fibrosis. Both coffee and tea consumption are associated with less likelihood of having MetS but further research with better designed studies is needed.