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Nutrients Jun 2022Iron-deficiency anemia is the most frequent nutritional deficiency, with women of reproductive age being particularly at risk of its development. The aim of the... (Review)
Review
Iron-deficiency anemia is the most frequent nutritional deficiency, with women of reproductive age being particularly at risk of its development. The aim of the systematic review was to assess the effectiveness of dietary interventions to treat iron-deficiency anemia in women based on the randomized controlled trials. The systematic review was conducted according to the PRISMA guidelines and registered in the PROSPERO database (CRD42021261235). The searching procedure was based on PubMed and Web of Science databases, while it covered records published until June 2021. It included all randomized controlled trials assessing effectiveness of various dietary interventions on treatment of iron-deficiency anemia in women of childbearing age. The total number of 7825 records were screened, while 14 of them were finally included in the systematic review. The studies were screened, included, and reported, and the risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials by two independent researchers. The included studies compared the effectiveness of various dietary interventions with supplementation, placebo, control, or any other dietary intervention, while the assessed dietary interventions were based either on increasing iron supply and/or on increasing its absorption (by increasing vitamin C or vitamin D or decreasing phytate intake). The duration of applied intervention was diversified from 3 months or less, through 4 or 5 months, to half of a year or more. Among the assessed biochemical measures, the following were analyzed in majority of studies: hemoglobin, ferritin, transferrin receptor, hematocrit, and transferrin. The majority of included studies supported the influence of dietary interventions on the treatment of iron-deficiency anemia, as the applied dietary intervention was not effective in only three studies. The majority of included studies were assessed as characterized by medium risk of bias, while the overall risk was high for only four studies, which resulted from the randomization process, deviations from the intended interventions, and selection of the reported result. The majority of included studies were conducted for increasing iron supply and/or increasing vitamin C supply; however, only for the interventions including increasing iron supply and simultaneously increasing its absorption by vitamin C supply were all results confirmed effective. Vitamin D also seems to be an effective dietary treatment, but further studies are necessary to confirm the observations. Considering this fact, dietary interventions recommended for anemic female patients should include increased intake of iron and vitamin C.
Topics: Anemia, Iron-Deficiency; Ascorbic Acid; Dietary Supplements; Female; Humans; Iron; Randomized Controlled Trials as Topic; Vitamin D; Vitamins
PubMed: 35807904
DOI: 10.3390/nu14132724 -
Critical Reviews in Food Science and... 2019Postpartum depression (PPD) is a prevalent mood disorder estimated to affect 20%-40% of women worldwide after childbirth. In recent studies, the effect of vitamin D on...
Postpartum depression (PPD) is a prevalent mood disorder estimated to affect 20%-40% of women worldwide after childbirth. In recent studies, the effect of vitamin D on prevention of mood disorders and depression has been investigated, but it is still unclear how vitamin D may affect PPD. The evidence on the relevance between vitamin D deficiency and PPD is inconsistent, and assessment of the recent literature has not previously been carried out. Moreover, there are few clinical studies on PPD and vitamin D supplementation. Five studies have so far assessed the relationship between the levels of vitamin D and PPD. Findings from cohort studies suggest that vitamin-D deficiency is related to the incidence of PPD and vitamin D may play a significant role in the recovery of women with PPD, but it is uncertain whether these actions are the effect of vitamin D on the function of hypothalamic-pituitary-adrenal (HPA) axis, the levels of estradiol, serotonin, pro-inflammatory cytokines, and/or of other mechanisms involved in PPD.
Topics: Depression, Postpartum; Dietary Supplements; Female; Humans; Vitamin D; Vitamin D Deficiency
PubMed: 29393662
DOI: 10.1080/10408398.2017.1423276 -
Advances in Nutrition (Bethesda, Md.) May 2017Nutrition is considered to be a possible factor in the pathogenesis of the neurological disease multiple sclerosis (MS). Nutrition intervention studies suggest that diet... (Review)
Review
Nutrition is considered to be a possible factor in the pathogenesis of the neurological disease multiple sclerosis (MS). Nutrition intervention studies suggest that diet may be considered as a complementary treatment to control the progression of the disease; a systematic review of the literature on the influence of diet on MS was therefore conducted. The literature search was conducted by using Medlars Online International Literature (MEDLINE) via PubMed and Scopus. Forty-seven articles met the inclusion criteria. The reviewed articles assessed the relations between macro- and micronutrient intakes and MS incidence. The patients involved used alternative therapies (homeopathy), protocolized diets that included particular foods (herbal products such as grape seed extract, ginseng, blueberries, green tea, etc.), or dietary supplements such as vitamin D, carnitine, melatonin, or coenzyme Q10. Current studies suggest that high serum concentrations of vitamin D, a potent immunomodulator, may decrease the risk of MS and the risk of relapse and new lesions, while improving brain lesions and timed tandem walking. Experimental evidence suggests that serum vitamin D concentration is lower during MS relapses than in remission and is associated with a greater degree of disability [Expanded Disability Status Scale (EDSS) score >3]. The findings suggest that circulating vitamin D concentrations can be considered a biomarker of MS and supplemental vitamin D can be used therapeutically. Other studies point to a negative correlation between serum vitamin B-12 concentrations and EDSS score. Vitamin B-12 has fundamental roles in central nervous system function, especially in the methionine synthase-mediated conversion of homocysteine to methionine, which is essential for DNA and RNA synthesis. Therefore, vitamin B-12 deficiency may lead to an increase in the concentration of homocysteine. Further research is clearly necessary to determine whether treatment with vitamin B-12 supplements delays MS progression.
Topics: Diet; Dietary Supplements; Disease Progression; Humans; Multiple Sclerosis; Nutritional Status; Vitamin B 12; Vitamin B 12 Deficiency; Vitamin D; Vitamin D Deficiency; Vitamins
PubMed: 28507011
DOI: 10.3945/an.116.014191 -
JAMA Network Open Jul 2023Plant-based diets are known to improve cardiometabolic risk in the general population, but their effects on people at high risk of cardiovascular diseases (CVDs) remain... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Plant-based diets are known to improve cardiometabolic risk in the general population, but their effects on people at high risk of cardiovascular diseases (CVDs) remain inconclusive.
OBJECTIVE
To assess the association of vegetarian diets with major cardiometabolic risk factors, including low-density lipoprotein cholesterol (LDL-C), hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and body weight in people with or at high risk of CVDs.
DATA SOURCES
This meta-analysis was registered before the study was conducted. Systematic searches performed included Embase, MEDLINE, CINAHL, and CENTRAL from inception until July 31, 2021.
STUDY SELECTION
Eligible randomized clinical trials (RCTs) that delivered vegetarian diets in adults with or at high risk of CVDs and measured LDL-C, HbA1c or SBP were included. Of the 7871 records screened, 29 (0.4%; 20 studies) met inclusion criteria.
DATA EXTRACTION AND SYNTHESIS
Two reviewers independently extracted data including demographics, study design, sample size, and diet description, and performed risk of bias assessment. A random-effects model was used to assess mean changes in LDL-C, HbA1c, SBP, and body weight. The overall certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool.
MAIN OUTCOMES AND MEASURES
Mean differences between groups in changes (preintervention vs postintervention) of LDL-C, HbA1c, and SBP; secondary outcomes were changes in body weight and energy intake.
RESULTS
Twenty RCTs involving 1878 participants (range of mean age, 28-64 years) were included, and mean duration of intervention was 25.4 weeks (range, 2 to 24 months). Four studies targeted people with CVDs, 7 focused on diabetes, and 9 included people with at least 2 CVD risk factors. Overall, relative to all comparison diets, meta-analyses showed that consuming vegetarian diets for an average of 6 months was associated with decreased LDL-C, HbA1c, and body weight by 6.6 mg/dL (95% CI, -10.1 to -3.1), 0.24% (95% CI, -0.40 to -0.07), and 3.4 kg (95% CI, -4.9 to -2.0), respectively, but the association with SBP was not significant (-0.1 mm Hg; 95% CI, -2.8 to 2.6). The GRADE assessment showed a moderate level of evidence for LDL-C and HbA1c reduction.
CONCLUSIONS AND RELEVANCE
In this study, consuming a vegetarian diet was associated with significant improvements in LDL-C, HbA1c and body weight beyond standard therapy in individuals at high risk of CVDs. Additional high-quality trials are warranted to further elucidate the effects of healthy plant-based diets in people with CVDs.
Topics: Adult; Humans; Middle Aged; Cardiovascular Diseases; Cholesterol, LDL; Glycated Hemoglobin; Vegetarians; Research Design; Body Weight
PubMed: 37490288
DOI: 10.1001/jamanetworkopen.2023.25658 -
International Journal of Impotence... Apr 2021The objective was to study available evidence for ingredients of popular over-the-counter testosterone and erectile dysfunction (ED) supplements. The top 16 male...
The objective was to study available evidence for ingredients of popular over-the-counter testosterone and erectile dysfunction (ED) supplements. The top 16 male testosterone and 16 ED supplements in the USA were identified from the most popular online retailers: A1 Supplements, Amazon, Vitamin Shoppe, and Walmart. In total, 37 ingredients were identified and PUBMED online database was reviewed for randomized-controlled trials (RCT) studying their efficacy. Ingredients were categorized based on evidence quantity using an adapted version of the American Heart Association scoring system. In total, 16 ingredients from testosterone supplements and 21 from ED supplements were identified. Tribulus, Eurycoma longifolia, Zinc, L-arginine, Aspartate, Horny goat weed, and Yohimbine were most common. In all, 105 RCTs studying the identified ingredients were found. No whole supplement products have published RCT evidence. 19% of ingredients received an A grade for strong positive evidence with net positive evidence in two or more RCTs. In total, 68% received C or D grades for contradicting, negative, or lacking evidence. Overall, 69% of ingredients in testosterone supplements and 52% of ingredients in ED supplements have published RCT evidence. Many male supplements claim to improve testosterone or ED parameters; however, there is limited evidence, which should be considered when counseling patients.
Topics: Arginine; Dietary Supplements; Erectile Dysfunction; Humans; Male; Plant Extracts; Testosterone
PubMed: 32358510
DOI: 10.1038/s41443-020-0285-x -
Nutrients Dec 2016Recent literature has highlighted the possible role of vitamin D in atopic dermatitis (AD), and that vitamin D supplementation might help to treat AD. This study... (Meta-Analysis)
Meta-Analysis Review
Recent literature has highlighted the possible role of vitamin D in atopic dermatitis (AD), and that vitamin D supplementation might help to treat AD. This study determined the relationship between vitamin D level and AD, and assessed the efficacy of vitamin D supplementation. We searched the MEDLINE, EMBASE, and Cochrane databases up to May 2015. Observational studies and randomized controlled trials were included based on the available data on the serum 25-hydroxyvitamin D (25(OH)D) level and quantified data available for severity assessed using the Scoring Atopic Dermatitis (SCORAD) index or Eczema Area and Severity Index (EASI) score. Compared with healthy controls, the serum 25(OH)D level was lower in the AD patients of all ages (standardized mean difference = -2.03 ng/mL; 95% confidence interval (CI) = -2.52 to -0.78), and predominantly in the pediatric AD patients (standardized mean difference = -3.03 ng/mL; 95% CI = -4.76 to -1.29). In addition, the SCORAD index and EASI score decreased after vitamin D supplementation (standardized mean difference = -5.85; 95% CI = -7.66 to -4.05). This meta-analysis showed that serum vitamin D level was lower in the AD patients and vitamin D supplementation could be a new therapeutic option for AD.
Topics: Adolescent; Adult; Child; Child, Preschool; Dermatitis, Atopic; Dietary Supplements; Female; Humans; Male; Middle Aged; Nutrition Therapy; Observational Studies as Topic; Randomized Controlled Trials as Topic; Severity of Illness Index; Vitamin D; Vitamins; Young Adult
PubMed: 27918470
DOI: 10.3390/nu8120789 -
Ageing Research Reviews Jun 2023To evaluate the effect of vitamin D supplementation on cancer mortality in the general population and on prognosis in cancer patients, a systematic review and... (Meta-Analysis)
Meta-Analysis
To evaluate the effect of vitamin D supplementation on cancer mortality in the general population and on prognosis in cancer patients, a systematic review and meta-analysis of randomised, placebo-controlled trials (RCTs) and individual patient data (IPD) was conducted. Overall, 14 RCTs with a total of 104,727 participants (2015 cancer deaths) were identified and 7 RCTs, including 90 % of all study participants (n = 94,068), could be included in the IPD meta-analyses. The main meta-analysis of the 14 RCTs yielded a statistically non-significant reduction in cancer mortality by 6 % (risk ratio (RR) [95%-confidence interval (95%CI)]: 0.94 [0.86-1.02]). Subgroup analyses revealed a 12 % lower cancer mortality in the vitamin D group compared with the placebo group in 10 trials with a daily dosing regimen (RR [95%CI]: 0.88 [0.78-0.98]), whereas no mortality reduction was seen in 4 trials using a bolus regimen (RR [95%CI]: 1.07 [0.91-1.24]; p-value for interaction: 0.042). The IPD meta-analysis (RR [95%CI]: 0.93 [0.84; 1.02]) confirmed the finding of all trials. The IPD were used to test effect modification by age, sex, body mass index, ethnicity, baseline serum 25-hydroxyvitamin D concentration, adherence and cancer-related factors but no statistically significant findings were obtained in meta-analyses of all trials. When restricted to trials with daily dosing in a post-hoc analysis, adults aged ≥ 70 years (RR [95%CI]: 0.83 [0.77; 0.98]) and subjects with vitamin D therapy initiation before cancer diagnosis (RR [95%CI]: 0.87 [0.69; 0.99]) appeared to benefit most from daily vitamin D supplementation. Measurements of baseline 25-hydroxyvitamin D levels and inclusion of other than non-Hispanic White adults were too sparse in the trials to draw conclusions. Results for all-cause and cancer-specific survival of participants with cancer were comparable to those obtained in the general population for cancer mortality. In conclusion, vitamin D did not reduce cancer mortality in the main meta-analysis of all RCTs because the observed risk reduction by 6 % was not statistically significant. However, a subgroup analysis revealed that vitamin D administered daily, in contrast to bolus supplementation, reduced cancer mortality by 12 %.
Topics: Humans; Cholecalciferol; Dietary Supplements; Neoplasms; Prognosis; Vitamin D
PubMed: 37004841
DOI: 10.1016/j.arr.2023.101923 -
The Journal of Nutrition Oct 2021Dietary saturated fat raises total cholesterol and LDL cholesterol levels. It is unclear whether these effects differ by the fatty acid chain lengths of saturated fats;... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Dietary saturated fat raises total cholesterol and LDL cholesterol levels. It is unclear whether these effects differ by the fatty acid chain lengths of saturated fats; particularly, it is unclear whether medium-chain fatty acids increase lipid levels.
OBJECTIVES
We conducted a systematic review to determine the effects of medium-chain triglyceride (MCT) oil, consisting almost exclusively of medium-chain fatty acids (6:0-10:0), on blood lipids.
METHODS
We searched Medline and Embase through March 2020 for randomized trials with a minimum 2-week intervention period that compared MCT oil with another fat or oil. Outcomes were total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride levels. Included studies were restricted to adults above 18 years of age. Studies conducted in populations receiving enteral or parenteral nutrition were excluded. Data were pooled using a random-effects meta-analysis.
RESULTS
Seven articles were included in the meta-analysis; LDL cholesterol and HDL cholesterol were reported in 6 studies. MCT oil intake did not affect total cholesterol (0.04 mmol/L; 95% CI, -0.11 to 0.20; I2 = 33.6%), LDL cholesterol (0.02 mmol/L; 95% CI, -0.13 to 0.17; I2 = 28.7%), or HDL cholesterol (-0.01 mmol/L; 95% CI, -0.10 to 0.09; I2 = 74.1%) levels, but did increase triglycerides (0.14 mmol/L; 95% CI, 0.01-0.27; I2 = 42.8%). Subgroup analyses showed that the effects of MCT oil on total cholesterol and LDL cholesterol differed based on the fatty acid profile of the control oil (Pinteraction = 0.003 and 0.008, respectively), with MCT oil increasing total cholesterol and LDL cholesterol when compared to a comparator consisting predominantly of unsaturated fatty acids, and with some evidence for reductions when compared to longer-chain SFAs.
CONCLUSIONS
MCT oil does not affect total cholesterol, LDL cholesterol, or HDL cholesterol levels, but does cause a small increase in triglycerides.
Topics: Cholesterol; Cholesterol, HDL; Dietary Fats; Humans; Lipids; Randomized Controlled Trials as Topic; Triglycerides
PubMed: 34255085
DOI: 10.1093/jn/nxab220 -
International Journal of Environmental... Mar 2021(1) Background: The purpose of the current meta-analysis was to investigate any positive or negative effects of ketogenic diets in athletes and provide an assessment of... (Meta-Analysis)
Meta-Analysis Review
(1) Background: The purpose of the current meta-analysis was to investigate any positive or negative effects of ketogenic diets in athletes and provide an assessment of the size of these effects. (2) Methods: Databases were used to select relevant studies up to January 2021 regarding the effects of ketogenic diets in athletes. Inclusion criteria were as follows: data before and after ketogenic diet use, being randomized controlled trials and presenting ketogenic diets and assessments of ketone status. Study subjects were required to be professional athletes. Review studies, pilot studies, and studies in which non-athletes were included were excluded from this meta-analysis. The outcome effect sizes in these selected studies were calculated by using the standardized mean difference statistic. (3) Results: Eight studies were selected for this meta-analysis. Athletes who consumed the ketogenic diet had reduced body fat percentages, respiratory exchange rates, and increased total cholesterol compared to athletes who did not consume this diet. However, body mass index, cardiorespiratory fitness, heart rate, HDL cholesterol, glucose level, and insulin level were unaffected by the diet. (4) Conclusions: Ketogenic diets had a beneficial effect by decreasing body fat percentage, but athletes with high total cholesterol level need to be monitored when instituting a ketogenic diet. Our study sample size was limited; therefore, additional studies may be needed to confirm the current findings. Further studies need to be conducted on changes in LDL cholesterol, HDL cholesterol, total cholesterol and ratio of LDL to HDL cholesterol.
Topics: Adipose Tissue; Athletes; Cholesterol, HDL; Diet; Diet, Ketogenic; Humans
PubMed: 33809153
DOI: 10.3390/ijerph18062912 -
Nutrients Mar 2021The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and... (Meta-Analysis)
Meta-Analysis
The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance.
Topics: Adult; Athletes; Blood Glucose; Blood Pressure; Body Composition; Body Mass Index; Cholesterol, LDL; Databases, Factual; Diet; Diet, Healthy; Diet, Paleolithic; Exercise; Glycated Hemoglobin; Health Status; Humans; Lipids; Randomized Controlled Trials as Topic; Triglycerides; Waist Circumference
PubMed: 33801152
DOI: 10.3390/nu13031019