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There is increasing evidence that both black and green tea are beneficial for prevention of cardiovascular disease (CVD). We conducted a systematic review and meta-analysis evaluating the effects of tea flavonoids on cardiovascular (CVD) and all-cause mortality outcomes.Searches across five databases including PubMed and Embase were conducted through November 2018 to identify randomized controlled trials (RCTs) and prospective cohort studies reporting cardiovascular and all-cause mortality outcomes. Two investigators independently conducted abstract and full-text screenings, data extractions, and risk of bias (ROB) assessments using the Nutrition Evidence Library Bias Assessment Tool (NEL BAT). Mixed-effects dose-response meta-regression and standard random-effects meta-analyses for outcomes with ≥ 4 studies were performed. 0 RCTs and 38 prospective cohort studies were included in the systematic review. NEL BAT scores ranged from 0–15 (0 being the lowest risk). Our linear meta-regression model showed that each cup increase in daily tea consumption (about 280 mg and 338 mg of total flavonoids for black and green tea, respectively) was associated with 3–4% lower risk of CVD mortality (predicted adjusted RR = 0.96; CI 0.93–0.99 for green tea and RR = 0.97; CI 0.94–0.99 for black tea). Furthermore, eachcup increase in daily tea consumption was associated a 2% lower risk of all-cause mortality (predicted adjusted relative risk (RR) = 0.98; 95% CI 0.97–0.99 for black tea and RR = 0.98; CI 0.96–0.99 for green tea, respectively). Two studies reported multivariable Cox regression analysis results for the relationship between black tea intake and risks of all-cause mortality outcomes. The results from these two studies were combined with our linear meta-regression result in a random-effects model meta-analysis and showed that each cup increase in daily black tea consumption was associated with an average of 3% lower risk of all-cause mortality (pooled adjusted RR = 0.97; 95% CI 0.87- 1.00) with large heterogeneity (I2 = 81.4%; p = 0.005). Current evidence indicates that increased tea consumption may reduce cardiovascular and all-cause mortality in a dose-response manner. This systematic review was registered on PROSPERO.

Osteoarthritis (OA) is a degenerative joint disease for which there are no disease-modifying drugs. It is a leading cause of disability in the UK. Increasing age and obesity are both major risk factors for OA and the health and economic burden of this disease will increase in the future. Focusing on compounds from the habitual diet that may prevent the onset or slow the progression of OA is a strategy that has been under-investigated to date. An approach that relies on dietary modification is clearly attractive in terms of risk/benefit and more likely to be implementable at the population level. However, before undertaking a full clinical trial to examine potential efficacy, detailed molecular studies are required in order to optimise the design. This review focuses on potential dietary factors that may reduce the risk or progression of OA, including micronutrients, fatty acids, flavonoids and other phytochemicals. It therefore ignores data coming from classical inflammatory arthritides and nutraceuticals such as glucosamine and chondroitin. In conclusion, diet offers a route by which the health of the joint can be protected and OA incidence or progression decreased. In a chronic disease, with risk factors increasing in the population and with no pharmaceutical cure, an understanding of this will be crucial.

The growing interest in the role of phyto-oestrogens in human health has prompted scientists to evaluate the risk : benefit which would result from consuming high levels of these compounds at different stages of the life cycle. These compounds have been shown to exert a wide range of hormonal and non-hormonal activities in animals and in vitro, and these activities suggest plausible mechanisms for potential health effects in human subjects consuming phyto-oestrogen-rich diets. In addition, experimental and epidemiological data are available supporting the concept that phyto-oestrogen-rich diets exert physiological effects in vivo; however, their relative importance to human health remains to be elucidated. Our understanding of factors involved in their absorption and metabolism, including the role of intestinal microflora, is limited, and these factors together with dose-related effects may well be important in determining clinical efficacy.

Anthocyanins (ACNs) are part of a phenolic group of compounds known as flavonoids; they are responsible for the red and purple colours of many plant based foods, for example blackcurrants, blueberries and blackberries which are major dietary sources of ACNs in the diet, along with red wine. It has previously been reported that red wine drinkers have higher levels of the n-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in their blood and cells (1) . In 2010 a study in rats showed that ACNs have the potential to increase plasma EPA and DHA levels (2) , attributed to their increased bioconversion from a-Linolenic acid (ALNA) into EPA and DHA. This project aimed to further investigate the impact of dietary ACNs on n-3 fatty acid concentrations and bioconversion in stored samples from a human and two rodent studies. Plasma samples were acquired from a study in which 26 healthy postmenopausal women had consumed 500mg/d ACNs as cyanidin glycosides (from elderberry) or placebo for 12 weeks. Serum, cortex, heart and muscle tissue samples were obtained from a study in which rats were fed a control diet, or a diet supplemented with either 2% (w/w) blueberry, 320 mg ACN extract/g feed or 80 mg flavanols/g feed for 6 weeks. Serum and liver samples were also analysed from a study in which rats were fed a diet supplemented with one of the following four for 8 weeks: Palm oil, Palm oil +ACN (240mg/Kg feed), Rapeseed oil, or Rapeseed oil +ACN (240mg/Kg feed). Fatty acid levels were analysed using GC-FID. The data was analysed using by 2-way ANOVA, followed by a Bonferroni’s multiple comparison test. As shown in Figure 1, ACN consumption in post-menopausal women had no significant effect on plasma levels of various fatty acids, including EPA and DHA. In addition, fatty acid analysis of the serum, liver, cortex, heart and muscle tissue samples from the two rodent studies showed that consumption of ACN had no significant effect on levels of EPA and DHA (data not shown).

Ethical approvalwas obtained from the St. ThomasOs Hospital Research Ethics committee and informed consent obtained from all subjects. Participantscompleted a food frequency questionnaire, which was used to calculate nutrient intake using values from the McCance and Widdowsonfood composition tables

of 0.66 0.41 m M. We explored the bioactivity ofthese metabolites on vascular health by measuring the effects on mediators of nitric oxide bioavailability including endothelial nitric oxidesynthase (eNOS), NADPH oxidase (NOX4) and superoxide. Protein expression of eNOS was measured by ELISA and NOX4 by westernblotting, while superoxide was measured indirectly via ferrocytochrome C oxidation (A

) does not appear achievable inhuman subjects. Furthermore, the in vitro mechanistic bioactivity of anthocyanins has been exclusively explored using aglycones andglycoside conjugates, despite a lack of evidence establishing these compounds as the biologically-available forms.As spontaneous degradation of anthocyanins to phenolic acids and aldehydes is reported to occur under experimental