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Antioxidant vitamins supplementation reduce endometriosis related pelvic pain in humans: a systematic review and meta-analysis.
Zheng, SH, Chen, XX, Chen, Y, Wu, ZC, Chen, XQ, Li, XL
Reproductive biology and endocrinology : RB&E. 2023;21(1):79
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Endometriosis is a common gynaecological disorder in reproductive-age women which leads to infertility and pain symptoms. Current pain management approaches involve medications and surgical treatments, but their side effects and risk of recurrence have led to the exploration of alternative options. The aim of this study was to clarify the potential effects of antioxidant vitamins supplementation on endometriosis. This study was a systematic review and meta-analysis of eleven studies, comprising a total of 589 patients. Results showed that antioxidant vitamins supplementation can effectively alleviate endometriosis-related pain and reduce inflammatory markers. Authors conclude that antioxidant vitamins supplementation can be considered as an alternative treatment either on its own or in combination with other methods for managing endometriosis-related pain. However, further research would help to provide a clearer understanding of the role of antioxidant vitamins supplementation in women with endometriosis.
Abstract
OBJECTIVE This study aimed to clarify the effect of antioxidant vitamins supplementation on endometriosis-related pain. METHODS A systematic search of PubMed, Web of Science, Cochrane Library, Scopus, and China National Knowledge Infrastructure (CNK) databases was conducted to identify relevant studies published in English and Chinese up to 16 March 2023. The search terms used were "endometriosis" OR "endometrioma" OR "endometrium" AND "antioxidant" OR "Vitamin C" OR "Vitamin E" OR "Vitamin D" OR "25-OHD" OR "25(OH)D" OR "25-hydroxyvitamin D". Eligible studies were randomized controlled trials (RCTs) that assessed pain scores using the Visual Analogue Scale (VAS). Mean differences or odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to evaluate the effect of antioxidant vitamins supplementation on endometriosis. The quality of the included studies was assessed using the Cochrane Risk of Bias Tool. The study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. RESULTS A total of 13 RCTs involving 589 patients were included in this meta-analysis. We identified 11 studies that evaluated the effect of antioxidant vitamins supplementation on endometriosis-related pain. The results indicated that the supplementation of antioxidant vitamins can effectively alleviate endometriosis-related pain. Subgroup analysis showed that the supplementation of vitamin E (with or without vitamin C) had a positive effect on improving clinical pelvic pain in patients with chronic pelvic pain. Conversely, supplementation of vitamin D was associated with a reduction in pelvic pain in endometriosis patients, but the difference was not statistically significant compared to the placebo. Additionally, we observed changes in oxidative stress markers following vitamin supplementation. Plasma malondialdehyde (MDA) concentration decreased in patients with endometriosis after antioxidant vitamin supplementation, and the plasma MDA level was inversely correlated with the time and dose of vitamin E and C supplementation. Furthermore, the inflammatory markers in peritoneal fluid, including RANTES, interleukin-6, and monocyte chemoattractant protein-1, significantly decreased after antioxidant therapy. These findings suggest that antioxidant vitamins may alleviate pain in endometriosis patients by reducing inflammation. CONCLUSIONS The included studies support the potential role of antioxidant vitamins in the management of endometriosis. Supplementation with antioxidant vitamins effectively reduced the severity of dysmenorrhea, improved dyspareunia and pelvic pain, and enhanced quality of life in these patients. Therefore, antioxidant vitamin therapy could be considered as an alternative treatment method, either alone or in combination with other approaches, for endometriosis-related pain. TRIAL REGISTRATION PROSPERO registration number: CRD42023415198.
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Improving Cognitive Function with Nutritional Supplements in Aging: A Comprehensive Narrative Review of Clinical Studies Investigating the Effects of Vitamins, Minerals, Antioxidants, and Other Dietary Supplements.
Fekete, M, Lehoczki, A, Tarantini, S, Fazekas-Pongor, V, Csípő, T, Csizmadia, Z, Varga, JT
Nutrients. 2023;15(24)
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Dementia has multiple mechanisms involved in its development, which makes treating it with pharmaceuticals a challenge due to the multiple drugs that would be required. Alternative approaches have included nutritional change and supplementation with certain nutrients, low levels of which, have been shown to be associated with poorer brain function. This review paper aimed to discuss potential nutritional supplements for use in dementia. The results showed that there were several supplements that had clinical data on their use for brain function, including vitamins, minerals, essential fatty acids, and naturally occurring plant chemicals. The data was very mixed between and within each of the supplements and showed that dosage and individual requirements play a large part in success of supplementation. It was concluded that there was clinical evidence to support the supplementation of vitamins B, C, D, E, magnesium, iron, selenium, and omega-3 for benefits to brain function, however several factors need to be considered including age, sex, nutritional status, lifestyle, stress levels, and physical activity. Healthcare professionals could use this study to understand that vitamins and minerals play a prominent role in brain health, but everyone has different nutritional requirements and that supplemental recommendations for brain function need to be individually tailored.
Abstract
Cognitive impairment and dementia are burgeoning public health concerns, especially given the increasing longevity of the global population. These conditions not only affect the quality of life of individuals and their families, but also pose significant economic burdens on healthcare systems. In this context, our comprehensive narrative review critically examines the role of nutritional supplements in mitigating cognitive decline. Amidst growing interest in non-pharmacological interventions for cognitive enhancement, this review delves into the efficacy of vitamins, minerals, antioxidants, and other dietary supplements. Through a systematic evaluation of randomized controlled trials, observational studies, and meta-analysis, this review focuses on outcomes such as memory enhancement, attention improvement, executive function support, and neuroprotection. The findings suggest a complex interplay between nutritional supplementation and cognitive health, with some supplements showing promising results and others displaying limited or context-dependent effectiveness. The review highlights the importance of dosage, bioavailability, and individual differences in response to supplementation. Additionally, it addresses safety concerns and potential interactions with conventional treatments. By providing a clear overview of current scientific knowledge, this review aims to guide healthcare professionals and researchers in making informed decisions about the use of nutritional supplements for cognitive health.
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The effects of olive leaf extract on cardiovascular risk factors in the general adult population: a systematic review and meta-analysis of randomized controlled trials.
Razmpoosh, E, Abdollahi, S, Mousavirad, M, Clark, CCT, Soltani, S
Diabetology & metabolic syndrome. 2022;14(1):151
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Modifiable unhealthy behaviours, such as sedentary lifestyle, smoking, and unhealthy food habits, are regarded as important contributors to the widespread prevalence of cardiovascular diseases (CVDs), which occur concurrently in overweight/obesity, hypertension, dyslipidaemia, hyperglycaemia, and inflammation. The aim of this study was to investigate whether olive leaf extract (OLE) could improve the major cardiovascular-related variables, including lipid profile, glucose haemostasis, blood pressure, as well as liver/kidney and inflammatory markers in the general adult population. This study is a systematic review and meta-analysis of twelve randomised controlled studies. Results show that OLE supplementation: - significantly decreased triglycerides and systolic blood pressure levels. - only had short-term positive effects on blood pressure and lipid profiles, which may be attributed to the active constituents in OLE. - had more profitable effects on the improvement of triglycerides, blood pressure, total cholesterol and low-density lipoprotein cholesterol measures among participants with hypertension and individuals with normal body weight. Authors conclude that stronger randomised controlled trial investigations, assessing different doses and durations of OLE, are required to better elucidate the effects of OLE supplementation.
Abstract
BACKGROUND The aim of this systematic review and meta-analysis was to determine the effect of olive leaf extract (OLE) supplementation on cardiovascular-related variables, including lipid, glycemic, inflammatory, liver and renal-related factors, as well as blood pressure. METHODS PubMed, ISI Web of Science, Scopus, and Cochrane library were searched, up to October 2021, for relevant controlled trials. Mean differences and standard deviations were pooled for all outcomes, using a random-effects model. The methodological quality, as well as quality of evidence were assessed using standard tools. RESULTS Twelve studies (n = 819 participants) were included in our analyses. Overall analyses showed that OLE supplementation significantly decreased triglyceride (TG) levels (WMD = - 9.51 mg/dl, 95% CI - 17.83, - 1.18; P = 0.025; I2 = 68.7%; P-heterogeneity = 0.004), and systolic blood pressure (SBP) (WMD = - 3.86 mmHg, 95% CI - 6.44, - 1.28 mmHg; P = 0.003; I2 = 19.9%; P-heterogeneity = 0.28). Subgroup analyses also revealed a significant improvement in SBP (- 4.81 mmHg) and diastolic blood pressure (- 2.45 mmHg), TG (- 14.42 mg/dl), total cholesterol (TC) (- 9.14 mg/dl), and low-density lipoprotein-C (LDL-C) (- 4.6 mg/dl) measurements, in patients with hypertension. Significant reductions were also observed in TC (- 6.69 mg/dl), TG (- 9.21 mg/dl), and SBP (- 7.05 mmHg) in normal-weight individuals. However, no meaningful changes were seen in glucose hemostasis, liver and kidney, or inflammatory markers. CONCLUSION The present study revealed that supplementation with OLE yielded beneficial effects for blood pressure and lipid profile in adults, especially in patients with hypertension. As the quality of evidence for glucose hemostasis variables, liver, kidney, and inflammatory markers, were low-to-very low, higher quality RCTs may impact the overarching results. This study was registered at PROSPERO with the code CRD42022302395.
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Effects of Antioxidants on Pain Perception in Patients with Fibromyalgia-A Systematic Review.
Fernández-Araque, A, Verde, Z, Torres-Ortega, C, Sainz-Gil, M, Velasco-Gonzalez, V, González-Bernal, JJ, Mielgo-Ayuso, J
Journal of clinical medicine. 2022;11(9)
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Fibromyalgia (FM) is characterised by widespread chronic pain, fatigue, sleep disturbances, and cognitive impairment. As a result of oxidative stress, reactive oxygen species (ROS) are produced and improperly disposed of, resulting in peripheral and central sensitisations, and a reduction of the pain threshold in FM patients. It is well known that antioxidants are protective against oxidative stress and that reducing antioxidant levels can result in increased pain in patients with FM. An overview of 17 studies was conducted to evaluate the effect of antioxidant supplementation on pain perception and the appropriate duration of treatment for FM patients in this systematic review. This systematic review found that supplementation with Fibromyalgine® (Fib) (that contains vitamin C, acerola ginger root, and freeze-dried royal jelly), 300-400 gm/d of coenzyme Q10 alone in combination with Pregabalin, ferric carboxymaltose, vitamin C, E, and Nigella sativa, magnesium + amitriptyline, acetyl L-carnitine, and Sun Chlorella™ green algae are effective in reducing pain perception in FM patients. In patients with FM, alpha-lipoic acid supplementation significantly reduced pain scores. 80% of FM patients reported reduced pain after supplement treatment for at least six weeks. There is a need for further robust long-term studies to confirm the effectiveness and clinical applicability of antioxidants in the management of FM, as well as to identify the pathophysiology of FM. This research may, however, be used by healthcare professionals to gain a better understanding of the potential benefits of antioxidants in the treatment of pain associated with FM.
Abstract
In recent years, antioxidant supplements have become popular to counteract the effects of oxidative stress in fibromyalgia and one of its most distressing symptoms, pain. The aim of this systematic review was to summarize the effects of antioxidant supplementation on pain levels perceived by patients diagnosed with fibromyalgia. The words used respected the medical search terms related to our objective including antioxidants, fibromyalgia, pain, and supplementation. Seventeen relevant articles were identified within Medline (PubMed), Scopus, Web of Science (WOS), the Cochrane Database of Systematic Review, and the Cochrane Central Register of Controlled Trials. This review found that antioxidant supplementation is efficient in reducing pain in nine of the studies reviewed. Studies with a duration of supplementation of at least 6 weeks showed a benefit on pain perception in 80% of the patients included in these studies. The benefits shown by vitamins and coenzyme Q10 are remarkable. Further research is needed to identify the effects of other types of antioxidants, such as extra virgin olive oil and turmeric. More homogeneous interventions in terms of antioxidant doses administered and duration would allow the effects on pain to be addressed more comprehensively.
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Plant-Based Diets for Cardiovascular Safety and Performance in Endurance Sports.
Barnard, ND, Goldman, DM, Loomis, JF, Kahleova, H, Levin, SM, Neabore, S, Batts, TC
Nutrients. 2019;11(1)
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Studies suggest that endurance athletes are at higher risk of some types of heart disease. This review looked at the ability of plant-based diets to reduce risk and affect athletic performance. The authors found evidence that plant-based diets are associated with beneficial effects on health, such as reducing body fat, blood pressure, cholesterol, oxidative stress and inflammation. The authors of this review argue that there is a sound scientific basis for recommending plant-based diets to endurance athletes.
Abstract
Studies suggest that endurance athletes are at higher-than-average risk for atherosclerosis and myocardial damage. The ability of plant-based regimens to reduce risk and affect performance was reviewed. The effect of plant-based diets on cardiovascular risk factors, particularly plasma lipid concentrations, body weight, and blood pressure, and, as part of a healthful lifestyle, reversing existing atherosclerotic lesions, may provide a substantial measure of cardiovascular protection. In addition, plant-based diets may offer performance advantages. They have consistently been shown to reduce body fat, leading to a leaner body composition. Because plants are typically high in carbohydrate, they foster effective glycogen storage. By reducing blood viscosity and improving arterial flexibility and endothelial function, they may be expected to improve vascular flow and tissue oxygenation. Because many vegetables, fruits, and other plant-based foods are rich in antioxidants, they help reduce oxidative stress. Diets emphasizing plant foods have also been shown to reduce indicators of inflammation. These features of plant-based diets may present safety and performance advantages for endurance athletes. The purpose of this review was to explore the role of nutrition in providing cardioprotection, with a focus on plant-based diets previously shown to provide cardiac benefits.
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Sorting out the Value of Cruciferous Sprouts as Sources of Bioactive Compounds for Nutrition and Health.
Abellán, Á, Domínguez-Perles, R, Moreno, DA, García-Viguera, C
Nutrients. 2019;11(2)
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Vegetable sprouts are naturally rich in nutrients and other beneficial compounds. The sprouts of cruciferous vegetables, such as broccoli, kale, radish and pak choi, stand out due to their high contents of glucosinolates and phenolic compounds. The aim of this review was to compile and update the available knowledge on the production, nutritional composition, and health benefits of cruciferous sprouts. A number of studies have found that compounds found in cruciferous sprouts have anti-cancer, anti-inflammatory, and antioxidant capacities. Consumption of cruciferous sprouts contributes to healthy glucose, insulin and fat levels in the blood, and may be beneficial for the treatment of some metabolic disorders, such as type 2 diabetes. There is evidence that compounds in cruciferous sprouts are a useful tool for enhancing phase II enzymes in the liver, and benefit levels of interleukine-6, C-reactive protein, and tumour necrosis factor-α, and inhibition of NF-κB, among others. The active compounds in these sprouts have an influence on several cardiovascular processes, potentially reducing the risk of several diseases. The lack of consistency between studies with regard to sampling schedules, doses, sample size, etc. means that it is not possible at this time to state the effective dose of sprouts or their active compounds needed in order to achieve health benefits. Further research is needed in this area.
Abstract
Edible sprouts with germinating seeds of a few days of age are naturally rich in nutrients and other bioactive compounds. Among them, the cruciferous (Brassicaceae) sprouts stand out due to their high contents of glucosinolates (GLSs) and phenolic compounds. In order to obtain sprouts enriched in these phytochemicals, elicitation is being increasing used as a sustainable practice. Besides, the evidence regarding the bioavailability and the biological activity of these compounds after their dietary intake has also attracted growing interest in recent years, supporting the intake of the natural food instead of enriched ingredients or extracts. Also, there is a growing interest regarding their uses, consumption, and applications for health and wellbeing, in different industrial sectors. In this context, the present review aims to compile and update the available knowledge on the fundamental aspects of production, enrichment in composition, and the benefits upon consumption of diverse edible cruciferous sprouts, which are sources of phenolic compounds and glucosinolates, as well as the evidence on their biological actions in diverse pathophysiological situations and the molecular pathways involved.
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A plant-based diet for the prevention and treatment of type 2 diabetes.
McMacken, M, Shah, S
Journal of geriatric cardiology : JGC. 2017;14(5):342-354
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Type 2 diabetes is rising worldwide and increasing evidence indicates that dietary and lifestyle choices are key drivers of insulin resistance. Research on plant-based diets (PBDs) shows lower rates of type 2 diabetes, obesity, hypertension, hyperlipidaemia, cardiovascular disease and cancer. The aim of this review is to analyze the evidence supporting the use of PBDs for the prevention and treatment of type 2 diabetes and explore potential mechanisms of action. The existing literature points to the fact that PBDs simultaneously reduce the risk factors for cardiovascular disease including obesity, hypertension, hyperlipidaemia and inflammation. The proposed mechanism by which PBDs reduce insulin resistance is through the high fiber, antioxidant and magnesium content, all of which have been shown to promote insulin sensitivity. Based on this analysis, the authors conclude the PBD is highly beneficial for preventing and treating type 2 diabetes. Additionally, the authors agree with the mounting evidence for utilising a PBD to reduce the burden of diabetes and improve health overall.
Abstract
The prevalence of type 2 diabetes is rising worldwide, especially in older adults. Diet and lifestyle, particularly plant-based diets, are effective tools for type 2 diabetes prevention and management. Plant-based diets are eating patterns that emphasize legumes, whole grains, vegetables, fruits, nuts, and seeds and discourage most or all animal products. Cohort studies strongly support the role of plant-based diets, and food and nutrient components of plant-based diets, in reducing the risk of type 2 diabetes. Evidence from observational and interventional studies demonstrates the benefits of plant-based diets in treating type 2 diabetes and reducing key diabetes-related macrovascular and microvascular complications. Optimal macronutrient ratios for preventing and treating type 2 diabetes are controversial; the focus should instead be on eating patterns and actual foods. However, the evidence does suggest that the type and source of carbohydrate (unrefined versus refined), fats (monounsaturated and polyunsaturated versus saturated and trans), and protein (plant versus animal) play a major role in the prevention and management of type 2 diabetes. Multiple potential mechanisms underlie the benefits of a plant-based diet in ameliorating insulin resistance, including promotion of a healthy body weight, increases in fiber and phytonutrients, food-microbiome interactions, and decreases in saturated fat, advanced glycation endproducts, nitrosamines, and heme iron.
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Impact of Mediterranean diet on metabolic syndrome, cancer and longevity.
Di Daniele, N, Noce, A, Vidiri, MF, Moriconi, E, Marrone, G, Annicchiarico-Petruzzelli, M, D'Urso, G, Tesauro, M, Rovella, V, De Lorenzo, A
Oncotarget. 2017;8(5):8947-8979
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There is a growing link between being overweight or obese and the onset of certain cancers. The latest research shows that 30-35% of cancers may have a link to diet, and that metabolic syndromes involving obesity encourage the body to store metabolically active ‘sick fats’ in adipose tissue, which in turn causes inflammation and creates an environment for cancer to thrive. The Mediterranean diet (MD) is considered one of the healthiest in the world and rates of cancer and metabolic syndrome are lower in the Mediterranean region versus Northern Europe suggesting it may be helpful in prevention of obesity and cancer. The MD is characterised as a balanced combination of fruit and vegetables, fish, cereals, and polyunsaturated fats (such as olive oil), with a reduced consumption of meat and dairy products and moderate intake of alcohol, primarily red wine. The nutrients that are found in abundance in the MD have a mixture of anti-cancer, anti-inflammatory, and anti-obesity properties thanks to antioxidant elements, fibre and healthy polyunsaturated fats. Studies show these nutrients can help support multiple metabolic markers such as blood pressure, cholesterol, inflammation, and insulin sensitivity. In 2010, UNESCO proclaimed the MD as “World Cultural Heritage”. This diet represents a behavioural model, a “way of life”, that can ensure longer life expectancy and improve quality of life itself.
Abstract
Obesity symbolizes a major public health problem. Overweight and obesity are associated to the occurrence of the metabolic syndrome and to adipose tissue dysfunction. The adipose tissue is metabolically active and an endocrine organ, whose dysregulation causes a low-grade inflammatory state and ectopic fat depositions. The Mediterranean Diet represents a possible therapy for metabolic syndrome, preventing adiposopathy or "sick fat" formation.The Mediterranean Diet exerts protective effects in elderly subjects with and without baseline of chronic diseases. Recent studies have demonstrated a relationship between cancer and obesity. In the US, diet represents amount 30-35% of death causes related to cancer. Currently, the cancer is the second cause of death after cardiovascular diseases worldwide. Furthermore, populations living in the Mediterranean area have a decreased incidence of cancer compared with populations living in Northern Europe or the US, likely due to healthier dietary habits. The bioactive food components have a potential preventive action on cancer. The aims of this review are to evaluate the impact of Mediterranean Diet on onset, progression and regression of metabolic syndrome, cancer and on longevity.
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The cytokine storm of severe influenza and development of immunomodulatory therapy.
Liu, Q, Zhou, YH, Yang, ZQ
Cellular & molecular immunology. 2016;13(1):3-10
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The influenza virus is responsible for millions of severe cases and 250 000–500 000 deaths each year. Newly emerging influenza viruses have continued to challenge medical and public health systems. These infections in humans are accompanied by an aggressive pro-inflammatory response and insufficient control of an anti-inflammatory response, a combination of events called ‘cytokine storm’. The authors review the mechanisms involved with a cytokine storm and note that there is great interest in the association between polymorphisms (individual genetic variations) and host susceptibility, which may help explain why some individuals, but not others, seem relatively resistant to cytokine storm. The authors also review the use of immune modulating treatments and conclude that the most promising therapeutic approach may be a combination of S1PR (sphingosine-1-phosphate receptor 1) agonists¬, PPAR (peroxisome proliferator-activated receptor) agonists, COX-2 (cyclooxygenase-2) inhibitors, and antioxidants, including vitamin C, N-acetylcysteine (NAC), Glycyrrhizin (a compound from liquorice), polyphenols and flavonoids (plant-based antioxidants), and should be further studied in randomised clinical trials.
Abstract
Severe influenza remains unusual in its virulence for humans. Complications or ultimately death arising from these infections are often associated with hyperinduction of proinflammatory cytokine production, which is also known as 'cytokine storm'. For this disease, it has been proposed that immunomodulatory therapy may improve the outcome, with or without the combination of antiviral agents. Here, we review the current literature on how various effectors of the immune system initiate the cytokine storm and exacerbate pathological damage in hosts. We also review some of the current immunomodulatory strategies for the treatment of cytokine storms in severe influenza, including corticosteroids, peroxisome proliferator-activated receptor agonists, sphingosine-1-phosphate receptor 1 agonists, cyclooxygenase-2 inhibitors, antioxidants, anti-tumour-necrosis factor therapy, intravenous immunoglobulin therapy, statins, arbidol, herbs, and other potential therapeutic strategies.
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Olive oil intake is inversely related to cancer prevalence: a systematic review and a meta-analysis of 13,800 patients and 23,340 controls in 19 observational studies.
Psaltopoulou, T, Kosti, RI, Haidopoulos, D, Dimopoulos, M, Panagiotakos, DB
Lipids in health and disease. 2011;10:127
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Dietary fat, both in terms of quality and quantity, has been implicated in cancer development, either positively or negatively. The aim of this systematic review and meta-analysis of 19 studies (13,800 cancer patients; 23,340 controls) was to evaluate whether raw olive oil intake was associated with various types of cancer. Overall, the authors concluded that olive oil consumption was associated with lower odds of cancer development. The most prominent results were observed for breast cancer and cancer of the digestive tract. The authors call for more studies to investigate whether higher olive oil intake facilitates higher vegetable intake, thus maximising potential beneficial effects on cancer prevention and whether it is the mono-unsaturated fat component of olive oil or the anti-oxidant components that are responsible for the beneficial effects. Nutrition practitioners may want to incorporate olive oil intake into their client protocols as a preventative health measure.
Abstract
Dietary fat, both in terms of quantity and quality, has been implicated to cancer development, either positively or negatively. The aim of this work was to evaluate whether olive oil or monounsaturated fat intake was associated with the development of cancer. A systematic search of relevant studies, published in English, between 1990 and March 1, 2011, was performed through a computer-assisted literature tool (i.e., Pubmed). In total 38 studies were initially allocated; of them 19 case-control studies were finally studied (13800 cancer patients and 23340 controls were included). Random effects meta-analysis was applied in order to evaluate the research hypothesis. It was found that compared with the lowest, the highest category of olive oil consumption was associated with lower odds of having any type of cancer (log odds ratio = -0.41, 95%CI -0.53, -0.29, Cohran's Q = 47.52, p = 0.0002, I-sq = 62%); the latter was irrespective of the country of origin (Mediterranean or non-Mediterranean). Moreover, olive oil consumption was associated with lower odds of developing breast cancer (logOR = -0,45 95%CI -0.78 to -0.12), and a cancer of the digestive system (logOR = -0,36 95%CI -0.50 to -0.21), compared with the lowest intake. The strength and consistency of the findings states a hypothesis about the protective role of olive oil intake on cancer risk. However, it is still unclear whether olive oil's monounsaturated fatty acid content or its antioxidant components are responsible for its beneficial effects.