Effects of raw red onion consumption on metabolic features in overweight or obese women with polycystic ovary syndrome: a randomized controlled clinical trial

Antiobesity effects of onion (Allium cepa) in subjects with obesity: Systematic review and meta-analysis

Onions are rich in bioactive compounds and have been found to prevent various chronic diseases, including obesity. We performed a systematic review and meta-analysis to investigate the antiobesity effect of onions. Studies were identified in PubMed/MEDLINE, Embase, Web of Science, and CENTRAL focusing on clinical trials evaluating the antiobesity effects of onion in obese subjects. The risk of bias in the studies was evaluated using Cochrane's Risk of Bias tool. The effect of onions was analyzed using data from the selected studies, and the results were indicated by weighted mean difference with 95% CI. The I 2 static test was used to examine heterogeneity between the studies. A total of 38 studies were reviewed, of which five clinical trials meeting the criteria were selected. As investigational products, onion peels were used in four studies and onions were used in one study. Following systematic review, it was determined that the risk of bias was generally low, and body weight, BMI, waist circumference, and triglyceride levels were significantly reduced in the onion groups compared to the placebo. In conclusion, onion intake had an antiobesity effect by reducing body weight and body fat, and this effect was particularly pronounced with onion peel.

Incredible Combination of Lifestyle Modification and Herbal Remedies for Polycystic Ovarian Syndrome Management

A relatively frequent endocrine-metabolic illness called polycystic ovarian syndrome (PCOS) is characterized by polycystic ovaries, persistent anovulation, and hyperandrogenism, which cause symptoms such as irregular menstruation, infertility, and hirsutism. PCOS is linked to obesity, insulin resistance, and increased amounts of androgens, or male hormones. The sedentary lifestyle, dietary fluctuations, inactivity, and stress are other contributing variables. According to estimates from India in 2021, around 22.5% of women, or one in five Indian women, suffer from PCOS. Evidence-based medical care for PCOS places a strong focus on a multidisciplinary approach, as standard pharmacological treatment frequently targets a single symptom, may be contraindicated, has adverse effects, and is ineffective in certain circumstances. However, long-term treatments have drawbacks and are likely to be ineffective, making complementary and alternative therapies a worthwhile choice. Yoga science is a thorough treatment plan for a healthy body and mind that may eradicate PCOS's primary causes, stress and obesity. Some common herbal remedies, including Foeniculum vulgare, Tinospora cordifolia, Asparagus racemosus, Ocimum tenuiflorum, Areca catechu, and Lepidium meyenii, have been highly regarded sources that have the benefits of lowering PCOS as well as having hypoglycemic and antiobesity effects. In light of existing literature, women with PCOS experienced symptomatic relief, improvement in hormonal balance, and the quality of life by utilizing yoga practices as well as herbal remedies. In conclusion, combining lifestyle modifications with herbal remedies can be used in the management of PCOS as a holistic approach. Therefore, this review opens a new window for researchers all across the world to validate such findings.

Potential Role of Quercetin Glycosides as Anti-Atherosclerotic Food-Derived Factors for Human Health

Quercetin is a monomeric polyphenol of plant origin that belongs to the flavonol-type flavonoid subclass. Extensive studies using cultured cells and experimental model animals have demonstrated the anti-atherosclerotic effects of dietary quercetin in relation to the prevention of cardiovascular disease (CVD). As quercetin is exclusively present in plant-based foods in the form of glycosides, this review focuses on the bioavailability and bioefficacy of quercetin glycosides in relation to vascular health effects. Some glucose-bound glycosides are absorbed from the small intestine after glucuronide/sulfate conjugation. Both conjugated metabolites and deconjugated quercetin aglycones formed by plasma β-glucuronidase activity act as food-derived anti-atherogenic factors by exerting antioxidant, anti-inflammatory, and plasma low-density lipoprotein cholesterol-lowering effects. However, most quercetin glycosides reach the large intestine, where they are subject to gut microbiota-dependent catabolism resulting in deglycosylated aglycone and chain-scission products. These catabolites also affect vascular health after transfer into the circulation. Furthermore, quercetin glycosides may improve gut microbiota profiles. A variety of human cohort studies and intervention studies support the idea that the intake of quercetin glycoside-rich plant foods such as onion helps to prevent CVD. Thus, quercetin glycoside-rich foods offer potential benefits in terms of cardiovascular health and possible clinical applications.

Lifestyle management in polycystic ovary syndrome - beyond diet and physical activity

Polycystic ovary syndrome (PCOS) is a common condition affecting reproductive-aged women with reproductive, metabolic and psychological consequences. Weight and lifestyle (diet, physical activity and behavioural) management are first-line therapy in international evidence-based guidelines for PCOS. While these recommend following population-level diet and physical activity guidelines, there is ongoing interest and research in the potential benefit of including psychological and sleep interventions, as well as a range of traditional, complimentary and integrative medicine (TCIM) approaches, for optimal management of PCOS. There is limited evidence to recommend a specific diet composition for PCOS with approaches including modifying protein, carbohydrate or fat quality or quantity generally having similar effects on the presentations of PCOS. With regards to physical activity, promising evidence supports the provision of vigorous aerobic exercise, which has been shown to improve body composition, cardiorespiratory fitness and insulin resistance. Psychological and sleep interventions are also important considerations, with women displaying poor emotional wellbeing and higher rates of clinical and subclinical sleep disturbance, potentially limiting their ability to make positive lifestyle change. While optimising sleep and emotional wellbeing may aid symptom management in PCOS, research exploring the efficacy of clinical interventions is lacking. Uptake of TCIM approaches, in particular supplement and herbal medicine use, by women with PCOS is growing. However, there is currently insufficient evidence to support integration into routine clinical practice. Research investigating inositol supplementation have produced the most promising findings, showing improved metabolic profiles and reduced hyperandrogenism. Findings for other supplements, herbal medicines, acupuncture and yoga is so far inconsistent, and to reduce heterogeneity more research in specific PCOS populations, (e.g. defined age and BMI ranges) and consistent approaches to intervention delivery, duration and comparators are needed. While there are a range of lifestyle components in addition to population-recommendations for diet and physical activity of potential benefit in PCOS, robust clinical trials are warranted to expand the relatively limited evidence-base regarding holistic lifestyle management. With consumer interest in holistic healthcare rising, healthcare providers will be required to broaden their knowledge pertaining to how these therapies can be safely and appropriately utilised as adjuncts to conventional medical management.

Physiological Effects of Red-Colored Food-Derived Bioactive Compounds on Cardiovascular and Metabolic Diseases

Cardiovascular diseases (CVDs) are a major global cause of disease and mortality. CVDs are a group of disorders of the heart and blood vessels and include coronary artery disease, cerebrovascular disease, heart failure, and other conditions. The most important behavioral risk factors for heart disease and stroke are diet, physical activity, smoking, and drinking. Increased intake of fruits and vegetables is associated with reducing the risk of metabolic syndrome and CVDs. Red-colored foods align with cardiovascular health by protecting the heart and blood vessels. Red fruits and vegetables include tomatoes, strawberries, raspberries, cranberries, cherries, red apples, beets, and pomegranate. In vitro and in vivo studies, as well as clinical trials, show that the components of red foods demonstrate various potential health benefits against disease. In conclusion, there are many advantages to eating vegetable foods, especially red fruits and vegetables.

Effect of onion on blood lipid profile: A meta-analysis of randomized controlled trials

BACKGROUND

Studies indicate that onion supplementation may be effective in the treatment of dyslipidemia; however, the results remain controversial. This meta-analysis was conducted to evaluate potential benefits of onion on lipid profile.

METHODS

Up to 12 October 2020, PubMed, Cochrane Library, Web of Science, and Scopus were searched for randomized controlled trials evaluating the effects of onion on lipid profile. Mean differences (MD) and 95% confidence intervals (CI) were calculated. Meta-analysis was conducted using the fixed-effects model.

RESULTS

Ten trials with 446 participants in total were included in the meta-analysis. The pooled findings of 10 studies suggested that onion supplementation significantly improved high-density lipoprotein cholesterol (HDL) (MD: 2.29 mg/dl; 95% CI: 0.87, 3.72; I 2 = 0%) and low-density lipoprotein cholesterol (LDL) (MD: -6.64 mg/dl; 95% CI: -10.91, -2.36; I 2 = 32%),while onion supplementation did not significantly lower triglycerides (TG) (MD: -6.55 mg/dl; 95% CI: -15.64, 2.53; I 2 = 45%). Analysis of nine trials showed a significant reduction in total cholesterol (TC) (MD: -5.39 mg/dl; 95% CI: -10.68, -0.09; I 2 = 49%) in patients with onion supplementation compared to the control group.

CONCLUSION

In summary, supplementation of onion was beneficial to control dyslipidemia, including improving levels of HDL, LDL, and TC, but could not reduce TG level. The therapeutic benefits of onion for dyslipidemia need to be treated with caution considering that some of the results are not robust.

Polyphenols Rich Diets and Risk of Type 2 Diabetes

Type 2 diabetes is an increasing health concern worldwide. Both genetic and environmental risk factors as improper dietary habits or physical inactivity are known to be crucial in the pathogenesis of type 2 diabetes. Polyphenols are a group of plant-derived compounds with anti-inflammatory and antioxidant properties that are associated with a low prevalence of metabolic conditions characterized by insulin resistance, including obesity, diabetes, and hypertension. Moreover, there is now full awareness that foods that are rich in phytochemicals and polyphenols could play an important role in preserving human cardiovascular health and substantial clinical evidence indicates that regular dietary consumption of such foods affects favorably carbohydrate metabolism. This review briefly summarizes the evidence relating dietary patterns rich in polyphenols with glucose metabolism and highlights the potential benefits of these compounds in the prevention of type 2 diabetes.

A comprehensive review of clinical studies with herbal medicine on polycystic ovary syndrome (PCOS)

BACKGROUND

Polycystic ovary syndrome (PCOS) is a frequent medical condition characterized by both metabolic and reproductive disorders. Different pharmaceutical treatments have been proposed for PCOS. However, side effects of long-term treatments and their probable low efficacy have made complementary and alternative treatments a valuable option. Recent reports have indicated the increased use of complementary treatments. Herbal medicine, as part of complementary medicine, was find introduced in traditional Persian and Chinese medicine. Medicinal herbs have used for a long time in the treatment of gynecological and infertility problems of PCOS patients. In this study, we aimed to review herbal medicines used for PCOS worldwide.

METHODS

PubMed, Embase, Cochrane, and Scopus databases were searched for clinical trials and Randomized Controlled Trials based on related keywords. Data were collected from 1990 to 2019.

RESULTS

According to a multitude of studies, a wide spectrum of herbs can be used to improve various aspects of PCOS. Herbs such as Cinnamomum verum, Trigonella foenum-graecum L., and Vitex agnus-castus can impact on menstrual and ovulatory dysfunctions, obesity, insulin resistance, lipid-metabolism dysfunction, and androgen excess-related conditions.

CONCLUSION

Some plants as natural remedies may have beneficial effects on improving different aspects of PCOS; but further studies are needed to investigate their mechanisms and safety.

Lifestyle changes in women with polycystic ovary syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) affects 8% to 13% of reproductive-aged women and is associated with reproductive and metabolic dysfunction. Obesity worsens the presentation of PCOS and weight management (weight loss, maintenance or prevention of excess weight gain) is proposed as an initial treatment strategy, best achieved through lifestyle changes incorporating diet, exercise and behavioural interventions.

OBJECTIVES

To assess the effectiveness of lifestyle treatment in improving reproductive, anthropometric (weight and body composition), metabolic and quality of life factors in PCOS.

SEARCH METHODS

We searched the Cochrane Gynaecology and Fertility Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO, CINAHL and AMED (date of last search March 2018). We also searched controlled trials registries, conference abstracts, relevant journals, reference lists of relevant papers and reviews, and grey literature databases, with no language restrictions applied.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing lifestyle treatment (diet, exercise, behavioural or combined treatments) to minimal or no treatment in women with PCOS.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, assessed evidence quality and risk of bias, and extracted data. Our primary outcomes were live birth, miscarriage and pregnancy. We used inverse variance and fixed-effect models in the meta-analyses. We reported dichotomous outcomes as an odds ratio and continuous outcomes as a mean difference (MD) or standardised mean difference (SMD).

MAIN RESULTS

We included 15 studies with 498 participants. Ten studies compared physical activity to minimal dietary and behavioural intervention or no intervention. Five studies compared combined dietary, exercise and behavioural intervention to minimal intervention. One study compared behavioural intervention to minimal intervention. Risk of bias varied: eight studies had adequate sequence generation, seven had adequate clinician or outcome assessor blinding, seven had adequate allocation concealment, six had complete outcome data and six were free of selective reporting. No studies assessed the fertility primary outcomes of live birth or miscarriage. No studies reported the secondary reproductive outcome of menstrual regularity, as defined in this review.Lifestyle intervention may improve a secondary (endocrine) reproductive outcome, the free androgen index (FAI) (MD -1.11, 95% confidence interval (CI) -1.96 to -0.26, 6 RCTs, N = 204, I2 = 71%, low-quality evidence). Lifestyle intervention may reduce weight (kg) (MD -1.68 kg, 95% CI -2.66 to -0.70, 9 RCTs, N = 353, I2 = 47%, low-quality evidence). Lifestyle intervention may reduce body mass index (BMI) (kg/m2) (-0.34 kg/m2, 95% CI -0.68 to -0.01, 12 RCTs, N = 434, I2= 0%, low-quality evidence). We are uncertain of the effect of lifestyle intervention on glucose tolerance (glucose outcomes in oral glucose tolerance test) (mmol/L/minute) (SMD -0.02, 95% CI -0.38 to 0.33, 3 RCTs, N = 121, I2 = 0%, low-quality evidence).

AUTHORS' CONCLUSIONS

Lifestyle intervention may improve the free androgen index (FAI), weight and BMI in women with PCOS. We are uncertain of the effect of lifestyle intervention on glucose tolerance. There were no studies that looked at the effect of lifestyle intervention on live birth, miscarriage or menstrual regularity. Most studies in this review were of low quality mainly due to high or unclear risk of bias across most domains and high heterogeneity for the FAI outcome.

Relationship Between Steroid Hormones and Metabolic Profile in Women With Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is commonly associated with a higher cardiometabolic risk. The relationship between steroid hormones and cardiometabolic profile in PCOS has been evaluated, but no single hormonal predictor of this association has been identified to determine. To determine the relationship between steroid hormones and cardiometabolic risk factors in PCOS women. Study included 64 women diagnosed with PCOS. Fasting blood samples were analyzed for biochemical, metabolic parameters and sex steroid hormones. PCOS women with BMI≥27 had significantly higher serum free testosterone (FT), free androgen index (FAI), estrone (E1) (p=0.014, p=0.02, p=0.01) than those with normal weight. In all subjects E1 positively correlated with BMI (p=0.0067), serum insulin (p=0.0046), HOMA-IR (p=0.0125) and negatively with HDL-cholesterol (p=0.009). FAI positively correlated with serum cholesterol (p=0.0457), triacylglycerols (TAG) (p=0.0001), HOMA-IR (p=0.037), and glycemia (p=0.0001), negatively with HDL-cholesterol (p=0.029). In multiple linear regression model E1 most significantly predicted HOMA-IR, whereas FT/FAI predicted HDL-cholesterol and BMI. We conclude that PCOS women with marked overweight or obesity have higher FT, FAI and E1 as compared with nonobese PCOS subjects. E1 and FT may predict worse cardiometabolic profile in PCOS.

Dietary natural products as emerging lipoprotein(a)-lowering agents

Elevated plasma lipoprotein(a) (Lp(a)) levels are associated with an increased risk of cardiovascular disease (CVD). Hitherto, niacin has been the drug of choice to reduce elevated Lp(a) levels in hyperlipidemic patients but its efficacy in reducing CVD outcomes has been seriously questioned by recent clinical trials. Additional drugs may reduce to some extent plasma Lp(a) levels but the lack of a specific therapeutic indication for Lp(a)-lowering limits profoundly reduce their use. An attractive therapeutic option is natural products. In several preclinical and clinical studies as well as meta-analyses, natural products, including l-carnitine, coenzyme Q ₁₀ , and xuezhikang were shown to significantly decrease Lp(a) levels in patients with Lp(a) hyperlipoproteinemia. Other natural products, such as pectin, Ginkgo biloba, flaxseed, red wine, resveratrol and curcuminoids can also reduce elevated Lp(a) concentrations but to a lesser degree. In conclusion, aforementioned natural products may represent promising therapeutic agents for Lp(a) lowering.

Association between Dietary Inflammatory Index and Metabolic Syndrome in the General Korean Population

Inflammation is thought to be partly responsible for metabolic syndrome (MetS). Recently, dietary inflammatory index (DII) was developed to calculate the overall inflammatory potential of a diet. The objective of this study was to investigate the association between DII and MetS, as well as MetS components, using nationally representative survey data. The study sample consisted of 9291 Korean adults (aged 19⁻65 years, 3682 men and 5609 women) who participated in the sixth (2013⁻2015) Korea National Health and Nutrition Examination Survey. DII values were calculated using 24-h dietary recall data. Multivariable-adjusted logistic regression analysis was performed to identify the association between DII and MetS by sex. In the multivariate logistic regression model, the top DII quartile (Q4), was positively associated with MetS prevalence in men (Q4 vs. Q1, OR = 1.40; 95% CI = 1.06⁻1.85; p for linear trend = 0.008) and in postmenopausal women (Q4 vs. Q1, OR = 1.67; 95% CI = 1.15⁻2.44; p for linear trend = 0.008). The top DII quartile was also positively associated with the prevalence of hyperglycemia in men and the prevalence of central obesity in postmenopausal women. Further studies using prospective cohorts are needed to identify the causal relationship between DII and MetS.

DIETOS: A dietary recommender system for chronic diseases monitoring and management

BACKGROUND AND OBJECTIVE

Use of mobile and web-based applications for diet and weight management is currently increasing. However, the impact of known apps on clinical outcomes is not well-characterized so far. Moreover, availability of food recommender systems providing high quality nutritional advices to both healthy and diet-related chronic diseases users is very limited. In addition, the potentiality of nutraceutical properties of typical regional foods for improving app utility has not been exerted to this end. We present DIETOS, a recommender system for the adaptive delivery of nutrition contents to improve the quality of life of both healthy subjects and patients with diet-related chronic diseases. DIETOS provides highly specialized nutritional advices in different health conditions.

METHODS

DIETOS was projected to provide users with health profile and individual nutritional recommendation. Health profiling was based on user answers to dynamic real-time medical questionnaires. Furthermore, DIETOS contains catalogs of typical foods from Calabria, a southern Italian region. Several Calabrian foods have been inserted because of their nutraceutical properties widely reported in several quality studies. DIETOS includes some well known methods for user profiling (overlay profiling) and content adaptation (content selection) coming from general purpose adaptive web systems.

RESULTS

DIETOS has been validated for usability for both patients and specialists and for assessing the correctness of the profiling and recommendation, by enrolling 20 chronic kidney disease (CKD) patients at the Department of Nephrology and Dialysis, University Hospital, Catanzaro (Italy) and 20 age-matched healthy controls. Recruited subjects were invited to register to DIETOS and answer to medical questions to determine their health status. Based on our results, DIETOS has high specificity and sensitivity, allowing to determine a medical-controlled user's health profile and to perform a fine-grained recommendation that is better adapted to each user health status. The current version of DIETOS, available online at http://www.easyanalysis.it/dietos is not intended to be used by general users, but only for review purpose.

CONCLUSIONS

DIETOS is a novel food recommender system for healthy people and individuals affected by diet-related chronic diseases. The proposed system builds a users health profile and, accordingly, provides individualized nutritional recommendations, also with attention to food geographical origin.

Factors modulating bioavailability of quercetin-related flavonoids and the consequences of their vascular function

Nowadays dietary flavonoids attract much attention in the prevention of chronic diseases. Epidemiological and intervention studies strongly suggest that flavonoid intake has beneficial effects on vascular health. It is unlikely that flavonoids act as direct antioxidants, although oxidative stress profoundly contributes to vascular impairment leading to cardiovascular diseases. Instead, flavonoids may exert their function by tuning the cellular redox state to an adaptive response or tolerable stress. However, the optimum intake of flavonoids from supplements or diet has not been clarified yet, because a number of exogenous and endogenous factors modulating their bioavailability affect their vascular function. This review will focus on the current knowledge of the bioavailability and vascular function of quercetin as a representative of antioxidative flavonoids. Current intervention studies imply that intake of quercetin-rich onion improves vascular health. Onion may be superior to quercetin supplement from the viewpoint of quercetin bioavailability, probably because the food matrix enhances the intestinal absorption of quercetin. α-Glucosylation increases its bioavailability by elevating the accessibility to the absorptive cells. Prenylation may enhance bioaccumulation at the target site by increasing the cellular uptake. However, these chemical modifications do not guarantee health benefits to the vascular system. Dietary quercetin is exclusively present as their conjugated form in the blood stream. Quercetin may exert its vascular function as an aglycone within macrophage cells after inflammation-induced deconjugation and as conjugated metabolites by targeting endothelial cells. The relationship between the bioavailability and bio-efficacy should be clarified, to evaluate the vascular function of a wide variety of dietary flavonoids.

Consumption of Fresh Yellow Onion Ameliorates Hyperglycemia and Insulin Resistance in Breast Cancer Patients During Doxorubicin-Based Chemotherapy: A Randomized Controlled Clinical Trial

PURPOSE

Doxorubicin has been found to be associated with insulin resistance in animal models. Onion, a so-called functional food, is noted to affect the insulin signaling pathway of diabetes in vitro. To our knowledge, this is the first study to investigate the effects of consuming fresh yellow onions on insulin-related indices compared with a low-onion-containing diet among breast cancer (BC) patients treated with doxorubicin.

METHODS

This parallel-design, randomized, triple-blind, controlled clinical trial was conducted on 56 eligible BC patients (aged 30-63 years), diagnosed with invasive ductal carcinoma. Following their second cycle of chemotherapy, subjects were assigned in a stratified-random allocation to receive body mass index-dependent 100 to 160 g/d of onion as high onion group (HO; n = 28) or 30 to 40 g/d small onions in low onion group (LO; n = 28) for 8 weeks intervention. Participants, care givers, and those who assessed laboratory analyses were blinded to the assignments (IRCT Registry No.: IRCT2012103111335N1).

RESULTS

The compliance level of participants in the analysis was as high as 87.85%. A total of 23 available cases was analyzed in each group. The daily use of HO resulted in a significant decrease in serum fasting blood glucose and insulin levels in comparison with LO, over the period of study ( P < .001). Posttreatment with HO showed a significant decrease in homeostasis model of assessment-insulin resistance relative to changes in the LO group ( P < .05). A comparison of the changes that occurred throughout pre- and postdose treatments indicated improved quantitative insulin sensitivity check index ( P < .05) and controls on C-peptide in the HO group ( P < .05).

CONCLUSIONS

The present study demonstrated the effectiveness of onion to ameliorate hyperglycemia and insulin resistance in BC during doxorubicin-based chemotherapy.

Cardioprotective Efficacy of Red Wine Extract of Onion in Healthy Hypercholesterolemic Subjects

The objective of this study was to evaluate the efficacy of the red wine extract of onion (RO) and red wine (RW) on alleviating the risk factors of cardiovascular disease. During in vitro studies, various antioxidant activities [trolox equivalent antioxidant capacity (TEAC), DPPH, and H2 O2 scavenging ability] of RO and RW group were evaluated. Both RO and RW showed the maximum antioxidant capacity. During in vivo studies, 23 healthy hypercholesterolemic volunteers were randomly selected and assigned into two groups, who drunk 250 mL of RO (n = 11) or RW (n = 10) for 10 weeks. No significant changes were observed in anthropometric parameters (body weight, height, body mass, and BMI) in each group. Both RW and RO extracts elevated (p < 0.05) antioxidant activity and thereby prolonging the lag time of low-density lipoprotein oxidation. However, RO extract intake substantially suppressed (p < 0.05) the total cholesterol and low-density lipoprotein cholesterol levels when equivalence with RW thus, indicating its additional hypocholesterolemic effect. The inflammatory markers such as factor VII were also positively modulated by RO extract. Results indicated that RO extract consumption rendered better cardio protective effect than RW by altering cholesterol, improving antioxidation and suppressing inflammatory marker levels and thereby, attenuating the cardiovascular disease incidence.