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Nutrition and Cancer - NED Infobite
BANT's scientific NED InfoBites are designed to provide key elements of the latest research using plain language. They provide quick overviews on particular health issues and nutrition topics for a speedy introduction to the science. Visually attractive and easily shareable with clients and social media followers.
2024
Abstract
The incidence of cancer diagnosis is increasing and takes multiple forms. This NED Infobite brings evidence on hormone, digestive tract and non-digestive-tract cancers, in particular looking at dietary intake of lipids, flavonoids, allium vegetables, carotenoids and retinol.
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The effects of home-based exercise therapy for breast cancer-related fatigue induced by radical radiotherapy.
Mavropalias, G, Cormie, P, Peddle-McIntyre, CJ, Galvão, DA, Taaffe, DR, Schofield, C, Ray, S, Zissiadis, Y, Newton, RU
Breast cancer (Tokyo, Japan). 2023;30(1):139-150
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Breast cancer (BCa) is the most common form of cancer among women. Radiotherapy (RT) treatment is an important component of breast cancer treatment and is used with curative intent as well as for palliation. One commonly reported adverse side effect of RT is cancer related fatigue (CRF). The aims of this study were to (a) examine the effects of a 12-week home-based resistance and aerobic exercise program on CRF, health-related quality of life (HRQoL), and sleep quality and duration in BCa patients during and up to 12 months after RT, and (b) investigate how CRF, HRQoL, and sleep quality and duration affect the participants’ ability to follow their prescribed exercise program. This study was a two-arm, randomised controlled clinical trial. One hundred and six (n = 106) women with stage I-III BCa scheduled to receive radical RT were randomised into exercise (n = 51) or usual care (n = 55). Results show that CRF was present at baseline and persisted during RT. The exercise group had a quicker reduction in CRF compared to the usual care group. Moreover, there was a significant difference in the HRQoL during RT between groups, and a quicker HRQoL improvement post-RT for the exercise group, with no changes in sleep quality or duration. Additionally, less fatigue and less trouble sleeping were associated with greater weekly aerobic exercise duration and higher rating of perceived exertion during aerobic exercise. Authors conclude that home-based exercise during RT is safe and effective in reducing CRF and improving HRQoL
Abstract
BACKGROUND Radiotherapy (RT) can lead to cancer-related fatigue (CRF) and decreased health-related quality of life (HRQoL) in breast cancer patients. The purpose of this trial was to examine the feasibility and efficacy of a home-based resistance and aerobic exercise intervention for reducing CRF and improving HRQoL in breast cancer patients during RT. METHODS Women with breast cancer (N = 106) commencing RT were randomized to 12 weeks of home-based resistance and aerobic exercise (EX) or usual care/control (CON). The primary endpoint was CRF, with secondary endpoints of HRQoL, sleep duration and quality, and physical activity. Measurements were undertaken prior to RT, at completion of RT (~ 6 weeks), at completion of the intervention (12 weeks), and 6 and 12 months after RT completion, while CRF was also measured weekly during RT. RESULTS Eighty-nine women completed the study (EX = 43, CON = 46). Over the 12-week intervention, EX completed 1-2 resistance training sessions and accumulated 30-40 min of aerobic exercise weekly. For CRF, EX had a quicker recovery both during and post-RT compared to CON (p < 0.05). Moreover, there was a significant difference in HRQoL between groups at RT completion, with HRQoL unchanged in CON and higher in EX (p < 0.05). There was no change in sleep duration or quality for either group and there were no exercise-related adverse effects. CONCLUSIONS Home-based resistance and aerobic exercise during RT is safe, feasible, and effective in accelerating CRF recovery and improving HRQoL. Improvements in CRF and HRQoL for these patients can be achieved with smaller exercise dosages than stated in the generic recommendations for breast cancer.
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Diet. Nutrition, and cancer risk: what do we know and what is the way forward.
The BMJ Opinion provides comment and opinion written by The British Medical Journal's international community of readers, authors, and editors.
2023
Abstract
An in depth exploration of the current evidence linking diet and nutrition to the risk of several different types of cancer along the digestive tract and other common cancers such as breast, lung and prostate cancer. Besides providing an invaluable overview of the available nutrition research for each cancer type, it includes a useful summary of the World Cancer Research Fund (WCRF) and International Agency for Research on Cancer (IARC) conclusions regarding nutritional factors that may be contributing to the cancer burden worldwide, namely obesity and alcohol. The fact that evidence for other nutritional factors is currently inconclusive is thought to be largely due to the difficulty of performing research into the effects of nutrition on health.
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Effect of Tart Cherry on Aromatase Inhibitor-Induced Arthralgia (AIA) in Nonmetastatic Hormone-Positive Breast Cancer Patients: A Randomized Double-Blind Placebo-Controlled Trial.
Shenouda, M, Copley, R, Pacioles, T, Lebowicz, Y, Jamil, M, Akpanudo, S, Tirona, MT
Clinical breast cancer. 2022;22(1):e30-e36
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Aromatase inhibitors (AIs) are used as a treatment in breast cancer; however, a side effect of their use is often the development of aromatase inhibitor induced arthralgia (AIA), which manifests as pain in the joints, muscle weakness and reduced grip strength. Subsequently, many individuals stop taking AIs, resulting in poorer disease prognosis. Tart cherries (TC) have been shown in studies to help relieve joint pain and pain associated with exercise and so this RCT aimed to determine the effect of TC consumption on 60 breast cancer patients with AIA. The results showed that after 6-weeks individuals given TC had less pain, with some individuals reporting no pain at all. It was concluded that TC is a reliable and safe option for the management of AIA in breast cancer patients. This study could be used by healthcare professionals to recommend TC as an adjunct to aromatase inhibitor therapy in individuals with breast cancer who are experiencing pain.
Abstract
BACKGROUND Aromatase Inhibitor induced Arthralgia (AIA) can cause noncompliance leading to decreased breast-cancer survival. Effective interventions for AIA are limited. Tart cherry (TC) showed beneficial effect on musculoskeletal pain. 48 patients (Pts) randomized to TC versus placebo over 6 weeks, TC (23pts) had 34.7% mean pain decrease versus 1.4% in Placebo (25pts). TC can improve AIA in nonmetastatic breast-cancer patients. METHODS Randomized, placebo-controlled, double-blind trial. Eligible patients with NMHPBC on AI for at least 4 weeks were randomized to TC concentrate [50 tart cherries] vs. placebo (P) [syrup] in 1:1 model. Patients instructed to consume 1 Oz of concentrate in 8 Oz water daily for 6 weeks, and document their pain intensity at baseline, weekly and at study completion in a diary using Visual Analog Scale (VAS), with 0 mm indicating no pain, and 100 mm indicating highest pain. RESULTS Sixty patients were enrolled. Two patients did not complete the study due to diarrhea, and 10 patients were noncompliant. Forty-eight patients were included in the final analysis. TC group (23 pts) had 34.7% mean decrease in pain compared to 1.4% in P group (25 pts). This difference was statistically significant (Mann-Whitney U Test, P = .034). CONCLUSIONS Tart cherry can significantly improve AIA in nonmetastatic breast cancer patient.
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Mycotoxin-Linked Mutations and Cancer Risk: A Global Health Issue.
Ekwomadu, T, Mwanza, M, Musekiwa, A
International journal of environmental research and public health. 2022;19(13)
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Mycotoxins are toxic substances produced by fungi, which can be found in common foods like maize, wheat, nuts, and foods containing them. Mycotoxins such as aflatoxins, ochratoxin, fumonisins, zearalenone, and some Penicillium toxins can alter genetic material. According to previous studies, they can damage genetic material and affect cell growth. Usage of chemicals such as fertilizers and fungicides is a common practice in the agricultural industry to protect plants from fungus and to feed them. However, fungicides can accelerate mycotoxin production. 16 studies were included in this Systematic Review and 11 in Meta-Analysis. This research looked at the harmful effects of mycotoxins such as aflatoxins, fumonisins, ochratoxin, T2, zearalenone, and some Penicillium toxins in causing cancers. The researchers evaluated the link between aflatoxin exposure and liver cancer, fumonisin B1 exposure and liver cancer, zearalenone exposure and breast cancer, zearalenone exposure and cervical cancer, citrinine and patulin exposure and colorectal cancer, and NEO, HT-2, and T-2 exposure and Oesophageal cancer. This research did not show significant associations between various mycotoxins and cancer risk. As currently, most studies are primarily focused on aflatoxin; more robust studies are needed to assess the cancer risk associated with different mycotoxin exposure. Using the results of this study, healthcare professionals can gain a better understanding of how mycotoxins affect our bodies.
Abstract
Humans continue to be constantly exposed to mycotoxins, mainly through oral exposure (dietary), inhalation, or dermal contact. Recently, it has been of increasing interest to investigate mycotoxin-linked carcinogenicity. This systematic review was conducted to synthesize evidence of the association between mycotoxin-linked mutations and the risk of cancer, to provide an overview of the data linking exposure to different mycotoxins with human cancer risk, and to provide an update on current research on the risk of cancer associated with human exposure to mycotoxins. PRISMA guidelines were used when conducting the systematic review. PubMed, MEDLINE, and CINAHL electronic databases were comprehensively searched to extract the relevant studies published from inception to May 2022. A total of sixteen relevant studies (4907 participants) were identified and included in this review. Of these, twelve studies were from Asia, while four of the studies were conducted in Africa. The overall meta-analysis result found no significant association, although some of the studies confirmed an association between mycotoxin-linked mutations and primary liver cancer risk. Mainly, the experimental studies have shown associations between mycotoxin-linked mutations and cancer risk, and there is a need for researchers to confirm these links in epidemiological studies in order to guide public health policies and interventions.
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Consumption of industrial processed foods and risk of premenopausal breast cancer among Latin American women: the PRECAMA study.
Romieu, I, Khandpur, N, Katsikari, A, Biessy, C, Torres-Mejía, G, Ángeles-Llerenas, A, Alvarado-Cabrero, I, Sánchez, GI, Maldonado, ME, Porras, C, et al
BMJ nutrition, prevention & health. 2022;5(1):1-9
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Ultra-processed food intake has been linked to an increased risk of breast cancer in Western populations. This is the first study on ultra-processed food and breast cancer in young women from Latin America. In Latin America around 27% of breast cancers occur between 20 and 45 years and this is increasing. This population is currently undergoing rapid lifestyle and nutritional changes switching from a varied traditional diet (including corn tortillas, corn flour cakes, beans and other legumes, soup, homemade stew, vegetable, whole fruit) towards a more homogenous diet rich in industrial ultra-processed foods. In this case control study, the association of ultra-processed food intake to breast cancer risk was evaluated. 525 cases were included (women aged 20–45 years) and 525 matched population-based controls from Chile, Colombia, Costa Rica and Mexico. The degree of processing of foods was classified according to the NOVA classification. The results show an adverse effect of ultra-processed food intake on the risk of breast cancer in young Latin American women. Further studies are needed to confirm the results. Given the already proven chronic adverse health effects of ultra-processed foods, a decrease in these types of foods should be encouraged.
Abstract
Ultra-processed food intake has been linked to an increased risk of breast cancer in Western populations. No data are available in the Latin American population although the consumption of ultra-processed foods is increasing rapidly in this region. We evaluated the association of ultra-processed food intake to breast cancer risk in a case-control study including 525 cases (women aged 20-45 years) and 525 matched population-based controls from Chile, Colombia, Costa Rica and Mexico. The degree of processing of foods was classified according to the NOVA classification. Overall, the major contributors to ultra-processed food intake were ready-to-eat/heat foods (18.2%), cakes and desserts (16.7%), carbonated and industrial fruit juice beverages (16.7%), breakfast cereals (12.9%), sausages and reconstituted meat products (12.1%), industrial bread (6.1%), dairy products and derivatives (7.6%) and package savoury snacks (6.1%). Ultra-processed food intake was positively associated with the risk of breast cancer in adjusted models (OR T3-T1=1.93; 95% CI=1.11 to 3.35). Specifically, a higher risk was observed with oestrogen receptor positive breast cancer (ORT3-T1=2.44, (95% CI=1.01 to 5.90, P-trend=0.049), while no significant association was observed with oestrogen receptor negative breast cancer (ORT3-T1=1.87, 95% CI=0.43 to 8.13, P-trend=0.36). Our findings suggest that the consumption of ultra-processed foods might increase the risk of breast cancer in young women in Latin America. Further studies should confirm these findings and disentangle specific mechanisms relating ultra-processed food intake and carcinogenic processes in the breast.
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Sedentary behavior and cancer-an umbrella review and meta-analysis.
Hermelink, R, Leitzmann, MF, Markozannes, G, Tsilidis, K, Pukrop, T, Berger, F, Baurecht, H, Jochem, C
European journal of epidemiology. 2022;37(5):447-460
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Globally, cancer is one of the leading causes of death. In modern day-to-day life, sedentary behaviour is prevalent, with adults spending an average of 8.2 hours without any physical activity. It is believed that sedentary behaviour plays a significant role in the increase in all-cause mortality, obesity, chronic diseases, and cancer risk. The purpose of this review and meta-analysis was to examine previous studies that reported associations between sedentary behaviour and cancer incidence and all-cancer mortality. A total of 14 meta-analyses were included in the study, and the strength of the evidence for each association was rated. A significant association was found between sedentary behaviour and cancer incidence across various cancer sites, including ovarian, endometrial, colon, breast, rectal, and prostate cancers. All-cancer mortality also showed positively significant associations with sedentary behaviour. There is a need for further research to evaluate the mechanisms associated with sedentary behaviour and the development of cancer at various sites. However, the results of this study can be used by healthcare professionals to better understand the importance of recommending physical activity and other therapeutic strategies.
Abstract
Several systematic reviews and meta-analyses have summarized the association between sedentary behavior (SB) and cancer. However, the level of evidence and the potential for risk of bias remains unclear. This umbrella review summarized the current data on SB in relation to cancer incidence and mortality, with a particular emphasis on assessing the risk of bias. We searched PubMed, Web of Science and Cochrane Database for systematic reviews and meta-analyses on the association between SB and cancer incidence and mortality. We also searched for recent observational studies not yet included in existing meta-analyses. We re-calculated summary risk estimates for cancer incidence and mortality using random effects models. We included 14 meta-analyses covering 17 different cancer sites from 77 original studies. We found that high SB levels increase the risk for developing ovarian, endometrial, colon, breast, prostate, and rectal cancers, with relative risks of 1.29 (95% confidence interval (CI) = 1.08-1.56), 1.29 (95% CI = 1.16-1.45), 1.25 (95% CI = 1.16-1.33), 1.08 (95% CI = 1.04-1.11), 1.08 (95% CI = 1.00-1.17), and 1.07 (95% CI = 1.01-1.12), respectively. Also, we found an increased risk of cancer mortality of 1.18 (95% CI = 1.09-1.26). Most associations between SB and specific cancer sites were supported by a "suggestive" level of evidence. High levels of SB are associated with increased risk of several types of cancer and increased cancer mortality risk.
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Lipid Intake and Breast Cancer Risk: Is There a Link? A New Focus and Meta-Analysis.
Lodi, M, Kiehl, A, Qu, FL, Gabriele, V, Tomasetto, C, Mathelin, C
European journal of breast health. 2022;18(2):108-126
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Incidence of breast cancer is the leading cause of cancer-related mortality, accounting for 15.5% of all cancer-related deaths. However, there is a lack of complete understanding of the effects of different types of dietary lipids on breast cancer development, such as saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), dietary cholesterol, polyunsaturated fatty acids (PUFA), and unsaturated trans fatty acids (TFA). An evaluation of the effect of lipid consumption on breast cancer and the impact it has on menopausal status was conducted in this meta-analysis, which included forty-four studies. Increased saturated fatty acid intake was associated with an increased risk of breast cancer in postmenopausal women. However, breast cancer risk was not associated with increased consumption of total fat, SFA, MUFA, PUFA, and cholesterol in premenopausal women. The effects of estrogen and the release of proinflammatory cytokines by adipocytes should be evaluated, as well as other pathways that contribute to the development of breast cancer. There is a need for further robust studies to evaluate the effects of different types of lipid consumption on breast cancer. Although the association between SFA and breast cancer is weak, healthcare professionals can use this study's findings to better understand the detrimental effect of SFA, despite the fact that there is a great deal of heterogeneity in the current analysis.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The authors found no association between total fat, saturated fatty-acids, mono and poly-unsaturated fatty acids and cholesterol intake and breast cancer incidence in the general population and in pre-menopausal women.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
- Among lifestyle-related breast cancer risk factors, the role of diet in breast cancer remains uncertain.
- The authors highlight a weak association between high SFA consumption and breast cancer risk in post-menopausal women.
- The authors found no association between total fat, saturated fatty-acids, mono and poly-unsaturated fatty acids and cholesterol intake and breast cancer incidence in the general population and in pre-menopausal women.
Objectives
- To determine if there is an association between total lipid intake, saturated fatty acid (SFA), Poly- and Mono-Unsaturated Fatty Acid (PUFA and MUFA) and cholesterol intake and breast cancer risk.
Results
- Forty-four articles were included in the meta-analysis, consisting of 28 case-control studies and 16 cohort studies.
- In total, this meta-analysis involved 1,185,896 women, of whom 54,553 had breast cancer.
- There was no association between total fat, SFA, MUFA, PUFA and cholesterol intake and breast cancer in the general population and in pre-menopausal women.
- In postmenopausal women, high SFA consumption was associated with increased breast cancer risk in case-control studies [relative risk (RR): 1.12; confidence interval (CI) 95%: 1.03–1.21; p = 0.006 but not in cohort studies (RR: 1.01; CI 95%: 0.85–1.19; p = 0.93).
Limitations
- Studies included in the meta-analysis were carried out on populations from five continents with significant cultural and dietary diversity, and well as different types of oils used in the diet
Conclusion
- At this stage, the authors state it is not possible to establish nutritional recommendations regarding the consumption of lipids to decrease breast cancer risk.
Clinical practice applications:
- The results of this meta-analysis does not demonstrate a statistically significant link between high consumption of total lipids, PUFA, MUFA and cholesterol and the occurrence of breast cancer.
- However, the results suggest that there is an association between SFA intake and breast cancer risk in postmenopausal women, although this was only found in case-controlled studies and not cohort studies.
- While obesity is a known breast cancer risk factor after menopause, the link between the effect of diet and the effect of obesity on the breast may be through different mechanisms.
- The authors investigated if high lipid consumption acts on breast tissue by the same mechanisms as obesity, and found the association between SFA intake and breast cancer risk in postmenopausal women must be through other biological explanations.
- The authors found that while high SFA consumption may increase breast cancer risk among post-menopausal women, biological mechanisms linking SFA and breast cancerogenesis are still unknown.
- The meta-analysis found high blood cholesterol levels appear to increase the risk of breast cancer. However, the authors could not confirm that high dietary cholesterol intake is a risk factor for breast cancer. The authors postulated this may be in part due to the low proportion of cholesterol (about 30%) in the diet, while the rest comes from the degradation of lipids and carbohydrates by the liver.
Considerations for future research:
- As lipids can have different actions in the same family, studies should rather focus on specific lipid consumption
Abstract
Objective: To determine if there is an association between total lipid intake, saturated fatty acid (SFA), Poly- and Mono-Unsaturated Fatty Acid (PUFA and MUFA) and cholesterol intake and breast cancer risk. Materials and Methods: We conducted a systematic review of the literature and a meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We included all cohort and case-control studies published up to December 2020 with subgroup analysis according to menopausal status. Results: We included 44 articles for analysis. There was no association between total fat, SFA, MUFA, PUFA and cholesterol intake and breast cancer in the general population and in pre-menopausal women. In postmenopausal women, high SFA consumption was associated with increased breast cancer risk in case-control studies [relative risk (RR): 1.12; confidence interval (CI) 95%: 1.03-1.21; p = 0.006 but not in cohort studies (RR: 1.01; CI 95%: 0.85-1.19; p = 0.93). Conclusion: There was a weak association between high SFA consumption and breast cancer risk in post-menopausal women, however there was high heterogeneity for this analysis. As lipids can have different actions in the same family, studies should rather focus on specific lipid consumption.
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Coffee Consumption and Cancer Risk: An Assessment of the Health Implications Based on Recent Knowledge.
Pauwels, EKJ, Volterrani, D
Medical principles and practice : international journal of the Kuwait University, Health Science Centre. 2021;30(5):401-411
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Coffee is one of the most consumed beverages worldwide. Coffee is a good source of polyphenolic antioxidant and anti-inflammatory compounds such as caffeine, cafestol, kahweol, and chlorogenic acids. This review included one hundred and five cohort studies and meta-analyses to evaluate the relationship between coffee consumption and cancer of the breast, liver, oesophagus, stomach, pancreas, colorectum, kidney, bladder, prostate, and ovaries. The results of this review found an inverse association between coffee consumption and reduced risk of hepatocellular cancer. A slight risk reduction is observed against breast cancer in postmenopausal women. This review found no considerable association between coffee consumption and decreased cancer risk in other organs. Further robust studies are required to investigate the benefits of coffee consumption on cancer risk reduction due to the high heterogeneity of included studies. However, healthcare professionals can use the results of this study to understand the benefits of coffee consumption.
Abstract
A significant number of studies suggest that coffee consumption reduces cancer risk. This beneficial effect is usually ascribed to the presence of polyphenolic antioxidants and anti-inflammatory agents, including caffeine, cafestol, kahweol, and chlorogenic acids. To summarize recent literature on this subject, we performed a bibliographic search in PubMed and Embase over the period January 2005 to December 2020 to identify cohort studies and meta-analysis (with data collection ensuring quality of selected reports) that could provide quantitative data on the relationship between coffee consumption and common cancers. The totality of eligible scientific articles supports the evidence that coffee intake is inversely associated with risk of hepatocellular cancer and, to a slight extent, risk of breast cancer among postmenopausal women. As to the association with other organs, including the esophagus, pancreas, colorectum, kidneys, bladder, ovaries, and prostate, the results are less clear as reports reveal conflicting results or statistically nonsignificant data. Therefore, this overview does not provide broad-based conclusions. Important uncertainties include general study design, inhomogeneous patient sampling, different statistical analysis (deliberate), misreporting of socioeconomic status, education, coffee-brewing methods, consumption of caffeinated or decaffeinated coffee, smoking habits, and alcohol intake. Clearly, more epidemiologic research needs to be conducted before solid science-based recommendations can be made with regard to coffee consumption.
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Yogurt, cultured fermented milk, and health: a systematic review.
Savaiano, DA, Hutkins, RW
Nutrition reviews. 2021;79(5):599-614
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Many fermented foods are associated with health benefits, including fermented dairy products. Whereby diary itself is part of many nutritional guidelines, the guidances rarely distinguish between dairy and fermented dairy. This qualitative, systematic review sought to capture how consumption of fermented milk products influences health. The review included 108 studies, with over 70% reporting beneficial health outcomes. A small number of studies reported insignificant or neutral results and four unfavourable ones. The aspects of health that were considered included lactose digestion and tolerance, gut health and disease, diarrhoea and constipation, irritable bowel syndrome, cardiovascular health and disease, hypertension, blood lipids, cancer risk, colorectal/breast/prostate cancer, weight and body composition, diabetes risk and metabolic syndrome and bone health. The authors concluded that eating fermented dairy products aided lactose digestion and showed a consistent link with reduced risk of breast and colorectal cancer, type 2 diabetes, and improved weight maintenance, cardiovascular, bone, and gastrointestinal health. As dairy appears to increase the risk for prostate cancer, fermented dairy seems to be no different here to unfermented dairy at increasing the risk. Some potential mechanisms are proposed in the discussion section, how fermented dairy may elicit its health benefits. Given the predominant health benefits of fermented dairy, the authors encouraged to include fermented dairy into national nutrition guidelines and stress distinction between dairy and fermented dairy products. This review captures current evidence of the widespread health benefits of fermented dairy consumption worthwhile considering in clinical practice. In the absence of more clear findings in relation to prostate cancer and prevention, a cautious approach to dairy and fermented dairy consumption may be warranted.
Abstract
Consumption of yogurt and other fermented products is associated with improved health outcomes. Although dairy consumption is included in most dietary guidelines, there have been few specific recommendations for yogurt and cultured dairy products. A qualitative systematic review was conducted to determine the effect of consumption of fermented milk products on gastrointestinal and cardiovascular health, cancer risk, weight management, diabetes and metabolic health, and bone density using PRISMA guidelines. English language papers in PubMed were searched, with no date restrictions. In total, 1057 abstracts were screened, of which 602 were excluded owing to lack of appropriate controls, potential biases, and experimental design issues. The remaining 455 papers were independently reviewed by both authors and 108 studies were included in the final review. The authors met regularly to concur, through consensus, on relevance, methods, findings, quality, and conclusions. The included studies were published between 1979 and 2017. From the 108 included studies, 76 reported a favorable outcome of fermented milks on health and 67 of these were considered to be positive or neutral quality according to the Academy of Nutrition and Dietetics' Quality Criteria Checklist. Of the 32 remaining studies, the study outcomes were either not significant (28) or unfavorable (4), and most studies (18) were of neutral quality. A causal relationship exists between lactose digestion and tolerance and yogurt consumption, and consistent associations exist between fermented milk consumption and reduced risk of breast and colorectal cancer and type 2 diabetes, improved weight maintenance, and improved cardiovascular, bone, and gastrointestinal health. Further, an association exists between prostate cancer occurrence and dairy product consumption in general, with no difference between fermented and unfermented products. This article argues that yogurt and other fermented milk products provide favorable health outcomes beyond the milk from which these products are made and that consumption of these products should be encouraged as part of national dietary guidelines. Systematic review registration: PROSPERO registration no. CRD42017068953.