Tea or coffee? A case study on evidence for dietary advice

Consumption of Coffee, Tea, and Caffeine at Midlife, and the Risk of Physical Frailty in Late Life

OBJECTIVES

Our study evaluated the prospective association between the consumption of caffeine-containing beverages at midlife and the risk of physical frailty at late life within a population-based cohort of Chinese adults living in Singapore over a follow-up period of 20 years.

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

We used data from 12,583 participants from the baseline and third follow-up interviews of the Singapore Chinese Health Study (SCHS). Participants had a mean age of 53 years at baseline (1993-1998), and a mean age of 73 years during the third follow-up (2014-2017).

METHODS

At baseline, habitual consumption of caffeine-containing beverages was evaluated using a validated semi-quantitative food-frequency questionnaire. During the third follow-up, physical frailty was assessed using the modified Cardiovascular Health Study phenotype.

RESULTS

Compared with non-daily drinkers, those who drank 4 or more cups of coffee daily had reduced odds of physical frailty [odds ratio (OR), 0.54; 95% CI, 0.38-0.76]. Similarly, compared with those who hardly drank tea, participants who drank tea everyday also had reduced odds (OR, 0.82; 95% CI, 0.71-0.95). Total daily caffeine intake at midlife was associated with reduced likelihood of frailty at late life in a dose-response relationship (Ptrend < .001). Relative to their counterparts in the lowest quartile of daily caffeine intake (0-67.6 mg/d), participants in the highest quartile (223.0-910.4 mg/d) had an OR of 0.77 (95% CI, 0.66-0.91). Higher caffeine consumption was associated with lower likelihood of being in the slowest quintile for timed up-and-go (TUG) and weakest quintile for handgrip strength.

CONCLUSIONS AND IMPLICATIONS

In this cohort of Chinese adults, higher consumption of caffeine at midlife, via coffee and tea, was associated with a reduced likelihood of physical frailty in late life.

Coffee Consumption and the Incidence of Colorectal Cancer in Women

Background. Higher coffee consumption has been associated with decreased incidence of colorectal cancer. Our objective was to examine the relationship of coffee intake to colorectal cancer incidence in a large observational cohort of postmenopausal US women. Methods. Data were collected for the Women's Health Initiative Observational Study providing a follow-up period of 12.9 years. The mean age of our sample (N = 83,778 women) was 63.5 years. Daily coffee intake was grouped into 3 categories: None, moderate (>0-<4 cups), and high (4+ cups). Proportional hazards modeling was used to evaluate the relationship between coffee intake and colorectal cancer. Results. There were 1,282 (1.53%) new cases of colorectal cancer during follow-up. Compared to nondrinkers, moderate and high coffee drinkers had an increased incidence of colorectal cancer in multivariate analysis (HR 1.15, 1.02-1.29; HR 1.14, 0.93-1.38). Moderate drip brew coffee intake (HR 1.20, 1.05-1.36) and high nondrip brew coffee intake (HR 1.43, 1.01-2.02) were associated with increased odds. Conclusion. Our results suggesting increased incidence of colorectal cancer associated with higher coffee consumption contradict recent meta-analyses but agree with a number of other studies showing that coffee increases risk or has no effect. Brew method results are novel and warrant further research.

The role of number of meals, coffee intake, salt and type of cookware on colorectal cancer development in the context of the Mediterranean diet

OBJECTIVE

To investigate the association between dietary behaviours and colorectal cancer (CRC) in the context of the Mediterranean diet.

DESIGN

Case-control study.

SETTING

All patients (cases) were recruited from Saint Savvas Cancer Hospital and Alexandra General Hospital in Athens, Greece. Controls were voluntarily selected from the general population and matched to cases by age group (±10 years) and sex.

SUBJECTS

Two hundred and fifty cases with newly diagnosed CRC (mean age 63 (sd 12) years, 59·6 % males) and 250 controls matched on age and sex were studied. A standardized questionnaire assessing sociodemographic, clinical, lifestyle, dietary characteristics and nutritional behaviours was applied. Multiple logistic regression analysis was used to evaluate the aforementioned factors in addition to the MedDietScore (an index that evaluates adherence to the Mediterranean diet) on CRC development.

RESULTS

The higher the daily number of meals, the lower the likelihood of having CRC (OR = 0·74, 95 % CI 0·61, 0·89); coffee drinking was associated with higher likelihood of having CRC (OR = 3·27, 95 % CI 1·09, 9·8); the use of non-stick cookware was positively associated with CRC (OR = 1·57, 95 % CI 1·02, 2·4). However, these associations slightly lost their significance when adherence to the Mediterranean diet was taken into account. Moreover, a 1/75 increase in the modified-MedDietScore plus the aforementioned nutritional behaviours was associated with 13 % lower odds (95 % CI 0·83, 0·91, P < 0·001) of having CRC.

CONCLUSIONS

Nutritional behaviours in addition to dietary habits should be taken into account in detecting individuals prone to the development of CRC.

Risk factors for multiple myeloma: a hospital-based case-control study in Northwest China

BACKGROUND

The distinctive racial/ethnic and geographic distribution of multiple myeloma (MM) suggests that both family history and environmental factors may contribute to its development.

METHODS

A hospital-based case-control study consisting of 220 confirmed MM cases and 220 individually matched patient controls, by sex, age and hospital was carried out at 5 major hospitals in Northwest China. A questionnaire was used to obtain information on demographics, family history, and the frequency of food items consumed.

RESULTS

Based on multivariate analysis, a significant association between the risk of MM and family history of cancers in first degree relatives was observed (OR=4.03, 95% CI: 2.50-6.52). Fried food, cured/smoked food, black tea, and fish were not significantly associated with the risk of MM. Intake of shallot and garlic (OR=0.60, 95% CI: 0.43-0.85), soy food (OR=0.52, 95% CI: 0.36-0.75) and green tea (OR=0.38, 95% CI: 0.27-0.53) was significantly associated with a reduced risk of MM. In contrast, intake of brined vegetables and pickle was significantly associated with an increased risk (OR=2.03, 95% CI: 1.41-2.93). A more than multiplicative interaction on the decreased risk of MM was found between shallot/garlic and soy food.

CONCLUSION

Our study in Northwest China found an increased risk of MM with a family history of cancer, a diet characterized by low consumption of garlic, green tea and soy foods, and high consumption of pickled vegetables. The effect of green tea in reducing the risk of MM is an interesting new finding which should be further confirmed.

Variations of antioxidant properties and NO scavenging abilities during fermentation of tea

Tea is known as one of the most popular beverages in the world, which is believed to be beneficial for health. The main components in tea will change a lot depending on the different processes of fermentation, and thus the effects of different teas on human health may differ. The aim of this study is to explore the varied abilities of reactive oxygen species (ROS) and nitric oxide (NO) scavenging during the fermentation of tea. In this study, we conducted the in vitro experiments which involved some reaction systems indicating the abilities of scavenging ROS and NO. We also investigated the effects of tea and their components (catechins, theabrownins, caffeine) on the intracellular levels of ROS and NO, using Raw 264.7 cells as the model. We found that regardless of whether it was out of cell system or in Raw 264.7 cells, the abilities of scavenging ROS would decrease during the fermentation of tea. Further, the post-fermented pu-erh tea showed the best effect on inhibiting the lipopolysaccharide (LPS)-induced production of NO. These findings indicated that the fermentation process caused a change of the components which might be due to the changes of their antioxidant properties and NO scavenging abilities.

Association between green tea consumption and lung cancer risk

Green tea is a popular beverage and its health benefits are well known. However, inconsistent results have been reported in observational studies concerning the association between green tea consumption and the lung cancer risk. In this commentary, several methodological issues underlying the measurement of tea exposure are highlighted. The recommendations should be useful for designing and planning prospective cohort studies to ascertain the protective effect of green tea against lung cancer.

Lifestyle factors in people seeking infertility treatment - A review

BACKGROUND

Clinical infertility is a prevalent problem with significant financial and psychosocial costs. Modifiable lifestyle factors exist that may affect a person's time to conception and their chance of having a healthy, live birth. However, no guideline delineates what preconception advice should be offered to people presenting for infertility treatment.

AIM

The aim of this article is to review the literature regarding modifiable lifestyle factors in people seeking infertility treatment.

RESULTS

A person's time to pregnancy and their chance of having a healthy, live birth may be affected by factors such as weight, vitamin and iodine intake, alcohol and caffeine consumption, smoking, substance abuse, stress, environmental pollutants, vaccinations and oxidative stress.

CONCLUSIONS

Advice on modifiable lifestyle factors should be given to people presenting for infertility treatment to help them make positive changes that may improve their chances of pregnancy and delivering a healthy, live baby. Developing a guideline for this would be a prudent step towards helping clinicians to implement this aspect of preconception care.

Coffee, tea and caffeine intake and the risk of severe depression in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study

OBJECTIVE

Only a few cross-sectional studies have assessed the association between coffee, tea and caffeine and the risk of depression. Our aim was to determine the association in a population-based cohort study.

DESIGN

The population-based Kuopio Ischaemic Heart Disease Risk Factor Study cohort was recruited between 1984 and 1989 and followed until the end of 2006. We investigated the association between the intake of coffee, tea and caffeine and depression.

SETTING

Eastern Finland.

SUBJECTS

Middle-aged men (n 2232).

RESULTS

Altogether, forty-nine men received a discharge diagnosis of depression. We classified subjects into quartiles according to their mean daily coffee intake: non-drinkers (n 82), light drinkers (<375 ml/d, n 517), moderate drinkers (375-813 ml/d, n 1243) and heavy drinkers (>813 ml/d, n 390). Heavy drinkers had a decreased risk (RR = 0.28, 95 % CI 0.08, 0.98) for depression when compared with non-drinkers, after adjustment for age and examination years. Further adjustment for socio-economic status, alcohol consumption, smoking, maximal oxygen uptake, BMI and the energy-adjusted daily intakes of folate and PUFA did not attenuate this association (relative risk (RR) = 0.23, 95 % CI 0.06, 0.83). No associations were observed between depression and intake of tea (drinkers v. non-drinkers; RR = 1.19, 95 % CI 0.54, 2.23) or caffeine (highest quartile v. lowest quartile; RR = 0.99, 95 % CI 0.40, 2.45).

CONCLUSIONS

Coffee consumption may decrease the risk of depression, whereas no association was found for tea and caffeine intake.