Nutritional advice

Objectives:
Even though many studies have examined the possible effect of low-fat diet on breast cancer survival, the relationship remains unclear. Therefore, this review article has been conducted.

Does low-fat diet reduce risk of recurrence of breast cancer?

Study design:
This review article included 2 randomized controlled trials (RCTs) and 1 large multi-center prospective cohort study with 9,966 breast cancer patients.

Results and conclusions:
The investigators found post-diagnostic low-fat diet significantly reduced risk of recurrence of breast cancer by 23% [HR = 0.77, 95% CI = 0.63 to 0.94, p = 0.009] and all cause mortality of breast cancer by 17% [HR = 0.83, 95% CI = 0.69 to 1.00, p = 0.05].

The investigators concluded post-diagnostic low-fat diet reduces risk of recurrence of breast cancer. However, more trials of the relationship between low-fat diet and all-cause mortality of breast cancer are still needed.

Original title:
Effect of low-fat diet on breast cancer survival: a meta-analysis by Xing MY, Xu SZ and Shen P.

Link:
https://pubmed.ncbi.nlm.nih.gov/24606431/

Additional information of El Mondo:
Find more information/studies on fat consumption and breast cancer right here.

A low-fat diet is a diet with maximum 30 En% fat and maximum 7 En% saturated fat.  
30 En% fat means that the amounts of fat contribute 30% to the total calories (kcal) of the diet.
If the diet contains 2000 kcal, 66.7 grams of fat contribute 30% to this 2000 kcal.
1 gram of fat gives 9 kcal. Thus, 66.7 grams of fat provide 600 kcal and 600 kcal is 30% of 2000 kcal.

The most easy way to follow a diet a diet with maximum 30 En% fat and maximum 7 En% saturated fat is to choose only meals/products with maximum 30 En% fat and maximum 7 En% saturated fat. Check here which products contain maximum 30 En% fat and maximum 7 En% saturated fat.

However, the most practical way to follow a diet with maximum 30 En% fat and maximum 7 En% saturated fat is, all meals/products that you eat on a daily basis should contain on average maximum 30 En% fat and maximum 7 En% saturated fat.

To do this, use the 7-points nutritional profile app to see whether your daily diet contains maximum 30 En% fat and maximum 7 En% saturated fat.

Objectives:
Lung cancer is the most common cause of cancer death. Fruits and vegetables containing carotenoids and other antioxidants have been hypothesized to decrease lung cancer risk. Therefore, this meta-analysis (systematic review) has been conducted.

Do fruits and vegetables reduce lung cancer risk?

Study design:
This review article included prospective cohort studies up to December 2014.

Results and conclusions:
The investigators found in 18 studies, when comparing the highest fruits and vegetables with the lowest intakes, a significantly reduced risk of 14% for lung cancer [summary RR = 0.86 [95% CI = 0.78-0.94].

The investigators found in 25 studies, when comparing the highest vegetables with the lowest intakes, a significantly reduced risk of 8% for lung cancer [summary RR = 0.92 [95% CI = 0.87-0.97].

The investigators found in 29 studies, when comparing the highest fruits with the lowest intakes, a significantly reduced risk of 18% for lung cancer [summary RR = 0.82, 95% CI = 0.76-0.89].

The investigators found the association with fruit and vegetable intake was marginally significant in current smokers and inverse but not significant in former or never smokers.

The investigators found in 4 studies for each 100 g/day increase of fruits and vegetables, a significantly reduced risk of 4% for lung cancer [RR = 0.96, 95% CI = 0.94-0.98, I2 = 64%, n (cases) = 9,609].

The investigators found in 20 studies for each 100 g/day increase of vegetables, a significantly reduced risk of 6% for lung cancer [RR = 0.94, 95% CI = 0.89-0.98, I2 = 48%, n (cases) = 12,563].

The investigators found in 23 studies for each 100 g/day increase of fruits, a significantly reduced risk of 8% for lung cancer [RR = 0.92, 95% CI = 0.89-0.95, I2 = 57%, n (cases) = 14,506].

The investigators found the results were consistent among the different types of fruits and vegetables. However, the strength of the association differed across locations.

The investigators found evidence of a non-linear relationship [p 0.01] between fruit and vegetable intake and lung cancer risk showing that no further benefit is obtained when increasing consumption above ∼400g per day.

The investigators concluded fruits and/or vegetables intakes reduce risk of lung cancer with no further benefit when increasing consumption of fruits and vegetables above ∼400g per day.

Original title:
Fruits, vegetables and lung cancer risk: a systematic review and meta-analysis by Vieira AR, Abar L, […], Norat T.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/26371287

Additional information of El Mondo:
Find more information/studies on fruits and vegetables consumption and cancer right here.

Objectives:
Although exercise can improve insulin sensitivity, no adequate synthesis exists of exercise intervention studies with regard to their effect on insulin sensitivity. Therefore, this review article (meta-analysis) has beeen conducted.

Does exercise improve insuline sensitivity?

Study design:
This review article included data found across 2509 subjects (115 samples, 78 reports).
The median of mean age was 43 years.
The median of mean preintervention fasting insulin was 8 mU/L.

Results and conclusions:
The investigators found the overall mean effect size for 2-group postintervention comparisons was 0.38 [95% CI = 0.25-0.51, I2 = 0%] and for 2-group pre-post comparisons was 0.43 [95% CI = 0.30-0.56, I2 = 52%].

The investigators found higher mean insulin sensitivity for treatment than control subjects.

The investigators found the postintervention mean of 0.38 was consistent with treatment subjects ending studies with a mean fasting insulin of 6.8 mU/L if control participants’ mean fasting insulin were 7.9 mU/L.
Exploratory moderator analyses did not document different insulin sensitivity effect sizes across intervention characteristics or sample attributes.

The investigators concluded exercise is a valuable primary care and community health strategy for healthy adults to improve insulin sensitivity and lower the risk for diabetes conferred by insulin resistance.

Original title:
Insulin Sensitivity Following Exercise Interventions: Systematic Review and Meta-Analysis of Outcomes Among Healthy Adults by Conn VS, Koopman RJ, […], Hafdahl AR.

Link:
http://journals.sagepub.com/doi/pdf/10.1177/2150131913520328

Additional information of El Mondo:
Find more studies/information on physical activity and diabetes right here.

Objectives:
Evidence shows cruciferous vegetables exhibit chemoprotective properties, commonly attributed to their rich source of isothiocyanates. However, epidemiological data examining the association between cruciferous vegetable intake and colorectal neoplasms have been inconclusive. Therefore, this review article (meta-analysis) has been conducted.

Does cruciferous vegetable intake decrease colon cancer risk?

Study design:
This review article included 33 articles.
Subgroup analysis for individual cruciferae types (n = 8 studies) and GST polymorphism (n = 8 studies) were performed. Pooled adjusted odds ratios (ORs) comparing highest and lowest categories of dietary pattern scores were calculated.

Results and conclusions:
The investigators found when comparing highest with lowest categorie, cruciferous vegetable intake significantly reduced risk of colon cancer with 16% [OR = 0.84, 95% CI = 0.72-0.98, p value heterogeneity 0.001].

The investigators found when comparing highest with lowest categorie, broccoli intake significantly reduced risk of colorectal neoplasms with 20% [OR = 0.80, 95% CI = 0.65-0.99, p value heterogeneity = 0.02].

The investigators found stratification by GST genotype showed that the GSTT1 null genotype confered a reduction in colorectal neoplasms risk of 22% [OR = 0.78, 95% CI = 0.64-0.95, p value heterogeneity = 0.32].

The investigators concluded this meta-analysis provides support to the hypothesis that cruciferous vegetable intake protects against cancer of the colon. This meta-analysis also demonstrates the significance of gene-diet interactions and the importance of assessing individual cruciferous vegetables.

Original title:
Cruciferous vegetables and risk of colorectal neoplasms: a systematic review and meta-analysis by Tse G and Eslick GD.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/24341734

Additional information of El Mondo:
Find more studies/information on colon cancer and cruciferous vegetable intake right here.

Objectives:
Does physical activity reduce gastric cancer risk?

Study design:
This review article included 7 cohort studies (with mean reported follow-up ranging from 6 to 18.8 years) and 9 case control studies reporting 11,111 cases of gastric cancer among 1,606,760 patients.

There was no evidence of publication bias, both quantitatively [Begg and Mazumdar rank correlation test, p = 0.62] and qualitatively, on visual inspection of the funnel plot.

Results and conclusions:
The investigators found the risk of gastric cancer was 21% [OR = 0.79, 95% CI = 0.71-0.87, I2 = 55%]  lower among the most physically active people as compared with the least physically active people, after adjustment for important confounders, including age, obesity, and other risk factors for gastric cancer (smoking, alcohol, dietary patterns and socioeconomic status).
This protective effect was seen for gastric cancers in the cardia [OR = 0.80, 95% CI = 0.63-1.00, 4 studies] and distal stomach [OR = 0.63, 95% CI = 0.52-0.76, 5 studies].

The investigators found increasing physical activity was associated with a reduced risk of gastric cancer in both men [OR = 0.86, 95% CI = 0.75-0.99, 10 studies] and women [OR = 0.72, 95% CI = 0.55-0.94, 3 studies].

The investigators found in 12 studies that increased recreational physical activity showed an 18% reduction in gastric cancer risk [OR = 0.82, 95% CI = 0.72-0.94].

The investigators found the effect size was significantly smaller in high-quality studies [OR = 0.86, 95% CI = 0.75-0.99, 6 studies] as compared with low-quality studies [OR = 0.74, 95% CI = 0.69-0.81, 10 studies]. The results were consistent across sex, study quality, study design and geographic location.

The investigators concluded physical activity - especially recreational physical activity - is associated with reduced risk of gastric cancer. Lifestyle interventions focusing on increasing physical activity may decrease the global burden of gastric cancer, in addition to a myriad of other health benefits with being physically active, which include cardiovascular, metabolic and psychologic wellbeing.

Original title:
Physical Activity Is Associated with Reduced Risk of Gastric Cancer: A Systematic Review and Meta-analysis by Singh S, Varayil JE, […], Iyer PG.

Link:
http://cancerprevention.aacrjournals.org/content/7/1/12.abstract

Additional information of El Mondo:
Find more studies/information on physical activity and cancer right here.

Objectives:
Previous meta-analyses identified an inverse association of coffee consumption with the risk of type 2 diabetes. However, an updated meta-analysis is needed because new studies comparing the trends of association for caffeinated and decaffeinated coffee have since been published. Therefore, this review article has been conducted.

Does coffee intake reduce type 2 diabetes risk in a dose-response manner?

Study design:
This review article included 28 prospective cohort studies with 1109272 study participants and 45335 cases of type 2 diabetes. The follow-up duration ranged from 10 months to 20 years.

Results and conclusions:
The investigators found for compared with no or rare coffee consumption, a significant reduced risk of type 2 diabetes of:
8% [RR = 0.92, 95% CI = 0.90-0.94] for 1 cup/day;
15% [RR= 0.85, 95% CI = 0.82-0.88] for 2 cups/day;
21% [RR = 0.79, 95% CI = 0.75-0.83] for 3 cups/day;
25% [RR = 0.75, 95% CI = 0.71-0.80] for 4 cups/day;
29% [RR = 0.71, 95% CI = 0.65-0.76] for 5 cups/day and;
33% [RR = 0.67, 95% CI = 0.61-0.74] for 6 cups/day.

The investigators found a significant decreased risk of type 2 diabetes of 9% [RR = 0.91, 95% CI = 0.89-0.94] for an increasement of 1 cup/day caffeinated coffee and 6% [RR = 0.94, 95% CI = 0.91-0.98] for an increasement of 1 cup/day decaffeinated coffee [p for difference = 0.17].

The investigators concluded coffee consumption is inversely associated with the risk of type 2 diabetes in a dose-response manner. Both caffeinated and decaffeinated coffee is associated with reduced diabetes risk.

Original title:
Caffeinated and decaffeinated coffee consumption and risk of type 2 diabetes: a systematic review and a dose-response meta-analysis by Ding M, Bhupathiraju SN, […], Hu FB.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/24459154

Additional information of El Mondo:
Find more studies/information on coffee consumption and diabetes right here.
 

Objectives:
The prevalence of obesity and diabetes is increasing among children, adolescents and adults. Although estimates of the efficacy of exercise training on fasting insulin and insulin resistance have been provided for adults, similar estimates have not been provided for youth. Therefore, this review article has been conducted.

Study design:
This review article included 24 trials.

Results and conclusions:
The investigators found a small to moderate effect for exercise training on fasting insulin and improving insulin resistance in youth [Hedges’ d effect size = 0.48, 95% CI = 0.22-0.74, p 0.001 and 0.31, 95% CI = 0.06-0.56, p 0.05, respectively].

The investigators concluded there is evidence to support the use of exercise training in the prevention and treatment of type 2 diabetes in youth.

Original title:
Exercise and Insulin Resistance in Youth: A Meta-Analysis by Fedewa MV, Gist NH, […], Dishman RK.

Link:
http://www.pediatricsdigest.mobi/content/133/1/e163.abstract

Additional information of El Mondo:
Find more information/studies on diabetes and sport nutrition right here.

Objectives:
The aim of this review article (meta-analysis) was to assess the clinical efficacy and safety of oral ginger for symptomatic treatment of osteoarthritis (OA).

Study design:
This review article included 5 RCTs with in total 593 patients.

The average age of the patients ranged from 47 years to 66 years and the percentage of women included in the studies ranged from 26% to 80%.
The dose of oral administration of ginger ranged from 500 mg/day to 1000 mg/day.
Trial duration ranged from 3 to 12 weeks.

Results and conclusions:
The investigators found compared to placebo, ginger intake significantly reduced pain [SMD = -0.30, 95% CI = -0.50 to -0.09, p = 0.005, I2 = 27%].

The investigators found compared to placebo, ginger intake showed a statistically significant reduction in disability [SMD = -0.22, 95% CI = -0.39 to -0.04, p = 0.01, I2 = 0%].

The investigators found patients given ginger were more than twice as likely to discontinue (due to adverse events) treatment compared to placebo [RR = 2.33, 95% CI = 1.04 to 5.22, p = 0.04, I2 = 0%].

The investigators concluded that 500-1000 mg/day oral ginger intake is able to reduce pain and disability in osteoarthritis patients.

Original title:
Efficacy and safety of ginger in osteoarthritis patients: a meta-analysis of randomized placebo-controlled trials by Bartels EM, Folmer VN, […], Christensen R.

Link:
http://www.oarsijournal.com/article/S1063-4584(14)01276-X/pdf

Additional information of El Mondo:
Find more information/studies on chronic diseases right here. 

Objectives:
The aim of this review article was to evaluate the diagnostic accuracy of ultrasound in assessing active Crohn’s disease (CD) in adults.

Study design:
This meta-analysis included 15 studies involving 1558 adults with active Crohn’s disease.

Results and conclusions:
The investigators found overall, the pooled sensitivity (0.88) and LR- (0.14) were not heterogeneous, whereas the pooled specificity [0.97, I2 = 72.9%] and LR + [15.10, I2 = 71.8 %] were.

The investigators found the DOR of ultrasound for assessing active CD was 121.70, with significant heterogeneity (I2 = 63.3%).
A symmetrical summary ROC curve was plotted showing that the area under the curve was 0.94, indicating good diagnostic accuracy.

The investigators found meta-regression and subgroup analysis showed that the disease location may be a major cause of heterogeneity.

The investigators concluded ultrasound has high diagnostic accuracy in detecting active Crohn’s disease in adults, especially for small bowel Crohn’s disease.

Original title:
Ultrasound as a diagnostic tool in detecting active Crohn’s disease: a meta-analysis of prospective studies by Dong J, Wang H, [...], Li J.

Link:
http://link.springer.com/article/10.1007/s00330-013-2973-0

Additional information of El Mondo:
Find more information/studies on chronic diseases right here. 

Objectives:
The association of red meat consumption with the risk of stomach cancer has been reported by many studies, with inconclusive results. Therefore, this review article has been conducted.

Does a high red meat consumption increase stomach cancer risk?

Study design:
This review article included a total of 18 studies (cohort and case-control studies) involving 1,228,327 subjects.

Results and conclusions:
The investigators found for the highest versus lowest categories of red meat intake a significant increased risk of 37% for gastric cancer [pooled RR = 1.37, 95% CI = 1.18-1.59, I2 = 67.6%, p 0.001].

The investigators found in population-based case-control studies, a significant increased risk of 58% for gastric cancer [pooled RR = 1.58, 95% CI = 1.22-2.06, I2 = 73.0%, p 0.001].

The investigators found in hospital-based case-control studies, a significant increased risk of 63% for gastric cancer [pooled RR = 1.63, 95% CI = 1.38-1.92, I2 = 19.1%, p = 0.284].

The investigators found, however, no association among cohort studies [RR = 1.00, 95% CI = 0.83-1.20, I2 = 33.9%, p = 0.158].

The investigators found the significant association was also presented in the subgroup analysis by geographic area (Asia, Europe), publication year (≥2000), sample size (1,000, ≥1,000) and quality score (7 stars, ≥7 stars).

The investigators found in dose-response analysis that every 100 g/day increment in red meat intake significant increased gastric cancer risk with 17% [RR = 1.17, 95% CI = 1.05-1.32].

The investigators found in linear regression model that the risk of gastric cancer increased with increasing level of red meat consumption.

The investigators concluded that a increased intake of red meat might be a risk factor for stomach cancer. Might be because the risk was not significant among cohort studies. Therefore, further larger prospective cohort studies are warranted to verify this association.

Original title:
Red meat consumption and stomach cancer risk: a meta-analysis by Song P, Lu M, […], Zhao Q.

Link:
https://link.springer.com/article/10.1007/s00432-014-1637-z

Additional information of El Mondo:
Find more studies/information on meat intake and cancer right here.
 

Objectives:
Does allium vegetable consumption reduce gastric cancer risk?

Study design:
This review article included 22 case-control and 4 cohort studies with more than 10,000 cases.

Results and conclusions:
The investigators found in 10 case-control and 4 cohort studies for the highest versus lowest allium vegetables intake category a significant reduced risk of 22% for gastric cancer [OR = 0.78, 95% CI = 0.67-0.91].

The investigators found in 12 case-control studies for the highest versus lowest garlic intake category a significant reduced risk of 40% for gastric cancer [OR = 0.60, 95% CI = 0.47-0.76].

The investigators found in 13 case-control studies for the highest versus lowest onion intake category a significant reduced risk of 45% for gastric cancer [OR = 0.55, 95% CI = 0.41-0.73].

The investigators found in 4 cohort studies for the highest versus lowest allium vegetables intake category a non-significant increased risk of 2% for gastric cancer [RR = 1.02, 95% CI = 0.88-1.18]. Non-significant means no association with 95% confidence.

The investigators concluded high allium vegetable consumption, like garlic and onion is likely to reduce gastric cancer risk. Likely because this evidence is derived mainly from case-control studies. Therefore, further data from large cohorts are desirable for conclusive confirmation.

Original title:
Allium vegetable intake and gastric cancer: a case-control study and meta-analysis by Turati F, Pelucchi C, […], Galeone C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/25215621

Additional information of El Mondo:
Find more studies/information on allium vegetable consumption and cancer right here.

Objectives:
Garlic is a common spicy flavouring agent also used for certain therapeutic purposes. Garlic's effects on blood glucose have been the subject of many clinical and animal studies. However, studies reporting hypoglycemic effects of garlic in humans are conflicting. Therefore, this review article (meta-analysis) has been conducted.

Has garlic supplementation lowering effects on glycemic control measurements such as fasting blood glucose (FBG), postprandial glucose (PPG) and glycated haemoglobin (HbA1c)?

Study design:
This review article included a total of 7 RCTs (parallel design) that involved 9 comparisons with 513 subjects. The trials varied in size from 33 to 180 subjects. The study duration varied from 4 to 24 week (median: 12 week). The trials enrolled male and female subjects, both healthy and with diabetes.

Doses of garlic in the treatment group ranged from 600 to 1500 mg/d.

Results and conclusions:
The investigators found pooled analyses showed that garlic supplementation resulted in a statistically significant lowering in fasting blood glucose [SMD = -1.67, 95% CI = -2.80 to -0.55, p = 0.004].

The investigators could not perform a pooled analyse for postprandial glucose (PPG) control and glycosylated haemoglobin (HbA1c) outcomes, because only 1 study included in the meta-analysis reported PPG variables and only 2 studies reported HbA1c variables.

The investigators concluded that garlic supplementation (600 to 1500 mg/d) during 12 weeks results in a lowering in fasting blood glucose. More trials are needed to investigate the effectiveness of garlic on HbA1c and PPG.

Original title:
Garlic intake lowers fasting blood glucose: meta-analysis of randomized controlled trials by Hou LQ, Liu YH and Zhang YY.

Link:
http://apjcn.nhri.org.tw/server/APJCN/24/4/575.pdf

Additional information of El Mondo:
Find more information/studies on diabetes and garlic right here.

Objectives:
Emerging randomized controlled trials (RCTs) investigating the effect of green tea or green tea extract (GTE) supplementation on blood pressure (BP) among overweight and obese adults reported inconsistent findings. Therefore, this review article has been conducted.

Does tea consumption decrease blood pressure among overweight and obese adults?

Study design:
This review article included 14 RCTs with 971 participants (47% women).

Results and conclusions:
The investigators found green tea or green tea extract supplementation compared with placebo, significantly reduced systolic blood pressure with 1.42 mmHg [95% CI = -2.47 to -0.36, p  =  0.008, I2  =  52%, p for heterogeneity =  0.01 ] among overweight and obese adults.

The investigators found green tea or green tea extract supplementation compared with placebo, significantly reduced diastolic blood pressure with 1.25 mmHg [95% CI = -2.32 to -0.19, p = 0.02, I2 = 74%, p for heterogeneity   0.001] among overweight and obese adults.

The investigators found the quality of evidence across studies was low. Similar results were found in subgroup and sensitivity analyses.

The investigators concluded among overweight and obese adults, green tea or green tea extract supplementation is found to cause a small but significant reduction in blood pressure. However, more high-quality RCTs with large sample sizes are needed to further confirm the efficacy on blood pressure and make strong recommendations for green tea or green tea extract supplementation among the overweight and obese adults.

Original title:
Effect of green tea supplementation on blood pressure among overweight and obese adults: a systematic review and meta-analysis by Li G, Zhang Y, […], Holbrook A.

Link:
http://journals.lww.com/jhypertension/Abstract/2015/02000/Effect_of_green_tea_supplementation_on_blood.6.aspx

Additional information of El Mondo:
Find more information/studies on tea consumption right here.

Objectives:
There are conflicting reports on the correlation between manganese (Mn) levels and breast cancer. Therefore, this review article (meta-analysis) has been conducted.

Does manganese deficiency increase risk of breast cancer?

Study design:
This review article included 11 case-control studies involving 1302 subjects.

There was no evidence of publication bias. Sensitivity analysis showed that excluding any one study from the pooled analysis did not vary the results substantially.

Results and conclusions:
The investigators found the random-effects meta-analysis results indicated that subjects with breast cancer had lower manganese levels in serum and hair than healthy controls [SMD = -1.51, 95% CI = -2.47 to -0.56, I2 = 97.8%, p 0.001].

The investigators found in subgroup analysis that subjects with breast cancer had lower manganese levels than healthy controls in China [SMD = -1.32, 95% CI = -2.33 to -0.32] and Korea [SMD = -4.08, 95% CI = -4.63 to -3.54], but not in Turkey [SMD = -0.96, 95% CI = -3.19 to 1.27].

The investigators found in subgroup analysis that the differences of manganese levels between patients with breast cancer and healthy controls were similar in different sample specimens:
serum [SMD = -1.24, 95% CI = -2.31 to -0.16];
hair [SMD = -1.99, 95% CI = -3.91 to -0.06] and;
different types of manganese measurement:

ICP-AAS [SMD = -1.14, 95% CI = -2.24 to -0.04];
GFAAS [SMD = -1.94, 95% CI = -2.38 to -1.49];
ICP-AES [SMD = -3.77, 95% CI = -4.70 to -2.85]. These findings can well explain that  the between-study variability was the main source of heterogeneity.

The investigators concluded there is an association between deficient manganese concentration and breast cancer. However, the subgroup analysis found that there was contradiction regarding races and geography, like China and Turkey. Thus this finding needs further confirmation by trans-regional multicenter, long-term observation in a cohort design to obtain better understanding of causal relationships between manganese levels and breast cancer, through measuring manganese at baseline to investigate whether the highest manganese category versus lowest was associated with breast cancer risk.

Original title:
The association between deficient manganese levels and breast cancer: a meta-analysis by Shen F, Cai WS, [...],Xu B.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4443096/

Additional information of El Mondo:
Find more studies/information on manganese and breast cancer right here.

Objectives:
Approximately 5.7 million Americans carry the diagnosis of systolic heart failure (HF), a major health care burden. Heart failure is a known manifestation of thiamine deficiency (TD). Therefore, this review article has been conducted.

Is thiamine deficiency (vitamin B1 deficiency) a risk factor of systolic heart failure?

Study design:
This review article included 9 studies (observational studies and RCTs).

Results and conclusions:
The investigators found systolic heart failure patients had a higher risk of 153% of getting a thiamine deficiency [odds ratio = 2.53, 95% CI = 1.65-3.87].

The investigators found diuretic use, changes in dietary habits and altered thiamine absorption and metabolism were identified as possible mechanisms of thiamine deficiency in heart failure patients.

The investigators found small observational studies and randomized control trials suggested that thiamine supplementation in heart failure population could improve ejection fraction and reduce symptoms.

The investigators concluded thiamine deficiency is more prevalent in heart failure population, and its supplementation may be beneficial. The therapeutic role of thiamine in heart failure warrants further study.

Original title:
Determining the Role of Thiamine Deficiency in Systolic Heart Failure: A Meta-Analysis and Systematic Review by Jain A, Mehta R, […], Winchester DE.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/26497757

Additional information of El Mondo:
Find more information/studies on cardiovascular disease and vitamin B1 (thiamine) right here.

Objectives:
The association between meat consumption and the risk of hepatocellular carcinoma (HCC) is still inconclusive. Therefore, this review article has been conducted.

Does meat consumption increase risk of hepatocellular carcinoma?

Study design:
This review article included 7 cohort studies and 10 case-control studies.

Results and conclusions:
The investigators found for the highest vs. lowest consumption levels a non-significant increased risk for hepatocellular carcinoma of 10% [RR = 1.10, 95% CI = 0.85-1.42] for red meat, a non-significant increased risk of 1% [RR = 1.01, 95% CI = 0.79-1.28] for processed meat and a non-significant decreased risk of 3% [RR = 0.97, 95% CI = 0.85-1.11] for total meat. Non-significant means, there is no association with a 95% confidence.

The investigators found for the highest vs. lowest consumption levels a significant decreased risk for hepatocellular carcinoma of 31% [RR = 0.69, 95% CI = 0.58-0.81] for white meat and a significant decreased risk of 22% [RR = 0.78, 95% CI = 0.67-0.90] for fish. The results remained quite stable after stratification by the confounding factors.
Significant means, there is an association with a 95% confidence.

The investigators concluded a high level of white meat or fish consumption reduces the risk of hepatocellular carcinoma, while intake of red meat, processed meat or total meat is not associated with hepatocellular carcinoma risk. These results suggest that dietary intervention may be a promising approach for prevention of hepatocellular carcinoma, which still need to be confirmed by further well-designed prospective studies and experimental research.

Original title:
Systematic review with meta-analysis: meat consumption and the risk of hepatocellular carcinoma by Luo J, Yang Y, [...], Zhu Y.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/24588342

Additional information of El Mondo:
Find more studies/information on fish consumption, meat consumption and cancer right here.

A review article of cohort studies or case-control studies will answer the following question:
"Should I change my diet?".

Objectives:
Is there an association between meat intake and risk of esophageal cancer?

Study design:
This review article included 7 cohort studies and 28 case-control studies.

Results and conclusions:
The investigators found for the highest versus lowest total meat consumption categories a non-significant increased risk of 19% [95% CI = 0.98-1.46] for esophageal cancer.

The investigators found for the highest versus lowest red meat consumption categories a significant increased risk of 55% [95% CI = 1.22-1.96] for esophageal cancer.

The investigators found for the highest versus lowest processed meat consumption categories a significant increased risk of 33% [95% CI = 1.04-1.69] for esophageal cancer.

The investigators found for the highest versus lowest white meat consumption categories a significant decreased risk of 28% [95% CI = 0.60-0.86] for esophageal cancer.

The investigators found for the highest versus lowest poultry consumption categories a significant decreased risk of 17% [95% CI = 0.72-0.96] for esophageal cancer.

The investigators found for the highest versus lowest fish consumption categories a non-significant decreased risk of 5% [95% CI = 0.76-1.19] for esophageal cancer.

The investigators found when stratified by histological subtype, positive associations among esophageal squamous cell carcinoma and red meat, white meat and poultry and esophageal adenocarcinoma with total meat and processed meat.

The investigators concluded red meat and processed meat consumption increase risk of esophageal cancer, while white meat and poultry decrease risk of esophageal cancer. Fish consumption is not associated with incidence of esophageal cancer.

Original title:
Meat consumption is associated with esophageal cancer risk in a meat- and cancer-histological-type dependent manner by Zhu HC, Yang X, […], Sun XC.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/24395380

Additional information of El Mondo:
Find more studies/information on meat consumption and cancer right here.
 

Objectives:
Is there an association of intake of different vitamins and multiple-vitamin supplements and the incidence of colorectal cancer?

Study design:
This review article included 47 articles (cohort studies).

There was unacceptable heterogeneity for studies of multiple-vitamin supplements, so findings were inconclusive.

Results and conclusions:
The investigators found a significant reduced risk of 12% [multivariable-adjusted RR = 0.88, 95% CI = 0.81-0.95] for colorectal cancer when comparing the highest versus lowest dietary vitamin B9 (folate) intake. Significant means that there is an association with a 95% confidence.

The investigators found a significant reduced risk of 13% [multivariable-adjusted RR = 0.87, 95% CI = 0.77-0.99] for colorectal cancer when comparing the highest versus lowest dietary vitamin D intake. Significant because RR of 1 was not found in the 95% CI of 0.77 to 0.99. RR of 1 means no risk/association.

The investigators found a significant reduced risk of 12% [multivariable-adjusted RR = 0.88, 95% CI = 0.79-0.99] for colorectal cancer when comparing the highest versus lowest dietary vitamin B6 intake.

The investigators found a significant reduced risk of 14% [multivariable-adjusted RR = 0.86, 95% CI = 0.76-0.97] for colorectal cancer when comparing the highest versus lowest dietary vitamin B2 intake.

The investigators found, however, no association between both dietary vitamine A, C, E, B3 and B12 and the risk of colorectal cancer.

The investigators concluded high dietary vitamin B9 (folate), D, B6 and B2 intake reduces risk of colorectal cancer, but further study is needed.

Original title:
Vitamin and multiple-vitamin supplement intake and incidence of colorectal cancer: a meta-analysis of cohort studies by Liu Y, Yu Q, […], Li K.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/25491145

Additional information of El Mondo:
Find more studies/information on vitamines and colorectal cancer right here.

Objectives:
Red meat intake has been associated with risk of colorectal cancer, potentially mediated through heterocyclic amines. The metabolic efficiency of N-acetyltransferase 2 (NAT2) required for the metabolic activation of such amines is influenced by genetic variation. The interaction between red meat intake, NAT2 genotype and colorectal cancer has been inconsistently reported. Therefore, this review article has been conducted.

Is there an interaction between red meat intake, NAT2 genotype and colorectal cancer?

Study design:
This review article included 11 retrospective case-control studies with 8,290 colorectal cancer cases and 9,115 controls (subjects without colorectal cancer).

Results and conclusions:
The investigators found the highest quartile of red meat intake was associated with a 41% increased risk of colorectal cancer compared with the lowest quartile [OR = 1.41, 95% CI = 1.29-1.55].
However, a significant association was observed only for studies with retrospective diet data, not for studies with diet prospectively assessed before cancer diagnosis.

The investigators found when combining all studies, high red meat intake was similarly associated with colorectal cancer in those with a rapid/intermediate NAT2 genotype [OR = 1.38, 95% CI = 1.20-1.59] as with a slow genotype [OR = 1.43, 95% CI = 1.28-1.61, p interaction = 0.9].

The investigators concluded high red meat intake was associated with increased risk of colorectal cancer only from retrospective case-control studies and not modified by NAT2 enzyme activity.

Original title:
Red Meat Intake, NAT2, and Risk of Colorectal Cancer: A Pooled Analysis of 11 Studies by Ananthakrishnan AN, Du M, […], Chan AT.

Link:
http://cebp.aacrjournals.org/content/cebp/24/1/198.full.pdf

Additional information of El Mondo:
Find more studies/information on red meat consumption and colorectal cancer right here.

Objectives:
Previous observational studies regarding the existence of an association between folate intake and the risk of breast cancer have been inconsistent. Therefore, this review article has been conducted.

Does a higher dietary folate intake reduce breast cancer risk?

Study design:
This review article included 14 prospective cohort studies that reported data on 677,858 individuals.
The participant follow-up period ranged 4.7-17.4 years and the number of individuals per study ranged 11,699-88,818.
There was no publication bias.

Results and conclusions:
The investigators found no association between dietary folate intake and breast cancer risk for highest versus lowest category  [RR =  0.97, 95% CI = 0.90-1.05, p  = 0.451, I2 =  57.5%, p = 0.004].

The investigators found dose-response meta-analysis findings showed no association between the risk of breast cancer and a 100 µg/day increase in dietary folate intake [RR = 0.99, 95% CI = 0.98-1.01, p = 0.361, I2 = 66.2%, p 0.001].

The investigators found evidence of a nonlinear relationship between dietary folate intake and the risk of breast cancer.

A daily dietary folate intake of 200-320 µg was associated with a reduced risk of breast cancer. However, daily folate intake levels >400 µg was associated with a increased risk of breast cancer.

The investigators found overall folate intake level was associated with a reduced breast cancer risk of 36% if the patients had a daily alcohol intake >10 g [RR for highest versus lowest category = 0.64, 95% CI = 0.43-0.97].

The investigators concluded there are no effects of increased dietary folate intake on the incidence of breast cancer. But, a daily dietary folate intake of 200-320 µg was associated with a reduced risk of breast cancer. However, daily folate intake levels >400 µg was associated with a increased risk of breast cancer. Future studies should focus on specific populations in order to analyze primary breast cancer prevention.

Original title:
Folate Intake and the Risk of Breast Cancer: A Dose-Response Meta-Analysis of Prospective Studies by Zhang YF, Shi WW, […], Zhou YH.

Link:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4059748/

Additional information of El Mondo:
Find more studies/information on folate intake and breast cancer right here.
 

Objectives:
Does a high GI or GL diet increase risk of stroke events?

Study design:
This review article included 7 prospective cohort studies with 225000 participants free of diabetes from 6 different countries. 3046 stroke events were included and the follow-up range was 5 to 18 years.

Results and conclusions:
The investigators found a high GI diet was not significantly associated with a 10% increased risk for stroke events [pooled RR = 1.10, 95% CI = 0.99-1.21]. Not significantly means, there is no association with a 95% confidence.

However, the investigators found high GL was significantly associated with a 19% increased risk for stroke events [pooled RR = 1.19, 95% CI = 1.05-1.36].

The investigators found there was no significant association between high carbohydrate intake and stroke risk [RR = 1.12, 95% CI = 0.93-1.35].

The investigators concluded a daily high GL diet (but not GI diet) is the risk factor of stroke event. Further researches are needed to verify the meta-analyses results and study associated mechanisms.

Original title:
Carbohydrate Intake, Glycemic Index, Glycemic Load, and Stroke: A Meta-analysis of Prospective Cohort Studies by Cai X, Wang C, [...], Ding F.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/25593213

Additional information of El Mondo:
Find more information/studies on GL and GI diet right here.

Objectives:
Increasing evidence suggests that the Mediterranean diet can reduce the risk of cardiovascular disease. Olive oil is the hallmark of this dietary pattern. Therefore, this review article has been conducted.

Does olive oil consumption reduce risk of cardiovascular disease?

Study design:
This review article included case-control, prospective cohort studies and a randomised controlled trial investigating the specific association between olive oil consumption and the risk of cardiovascular disease (101,460 participants) or stroke (38,673 participants). The results of all observational studies were adjusted for total energy intake.

Evidence of heterogeneity was apparent for cardiovascular disease, but not for stroke. Both the Egger test (p = 0.06) and the funnel plot suggested small-study effects.

Results and conclusions:
The investigators found in case-controle studies a non-significant reduced risk of 27% [relative risk = 0.73, 95% CI = 0.44-1.21] for cardiovascular disease for a 25g increase in olive oil consumption.

The investigators found in cohort studies a non-significant reduced risk of 4% [relative risk = 0.96, 95% CI = 0.78-1.18] for cardiovascular disease for a 25g increase in olive oil consumption.

The investigators found in cohort studies olive oil consumption significantly reduced risk of stroke with 26% [relative risk = 0.74, 95% CI = 0.60-0.92].

The investigators found random-effects model showed a significant reduced risk of 18% [RR = 0.82, 95% CI = 0.70, 0.96] for combining all cardiovascular events (CHD and stroke).

The investigators concluded available studies support an inverse association of olive oil consumption with stroke and with stroke and cardiovascular disease combined. This finding is in agreement with the recent successful results of the PREDIMED randomised controlled trial.

Original title:
Olive oil consumption and risk of CHD and/or stroke: a meta-analysis of case-control, cohort and intervention studies by Martínez-González MA, Dominguez LJ and Delgado-Rodríguez M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/24775425

Additional information of El Mondo:
Find more studies/information on cardiovascular disease right here.

Objectives:
Is there an association between serum non-ceruloplasmin copper and Alzheimer's disease risk?

Study design:
This review article included studies carried out from 1996 until March 2013.

Ten studies were analyzed in the meta-analysis for Non-Cp copper and % Non-Cp copper reaching a pooled total of 599 Alzheimer's disease subjects and 867 controls.
For Adj-Cp copper, 14 studies were analyzed with a pooled total of 879 Alzheimer's disease subjects and 1712 controls.
27 studies were considered for systemic total copper meta-analysis, with a pooled total of 1393 Alzheimer's disease subjects and 2159 controls.

Results and conclusions:
The investigators found all copper indices analyzed were significantly higher in Alzheimer's disease subjects compared to healthy controls.

The investigators concluded serum non-ceruloplasmin copper is higher in Alzheimer's disease.

Original title:
Meta-analysis of serum non-ceruloplasmin copper in Alzheimer's disease by Squitti R, Simonelli I, […], Bush AI.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/24072069

Additional information of El Mondo:
Find more studies/information on elderly and copper.

Objectives:
Does DHA, alone or combined with EPA, contribute to improved memory function in older adults with mild memory complaints?

Study design:
This review article included 15 intervention trials and 13 observational studies. Most intervention trials were conducted with subjects ≥ 45 years of age (n = 11). The majority of studies were conducted in subjects without cognitive complaints (n = 9) and ranged from 28-730 days in duration, averaging 4-6 months.

Results and conclusions:
The investigators found episodic memory of subjects with mild memory complaints significantly improved in response to DHA supplementation, alone or in combination with EPA [p 0.004].

The investigators found regardless of cognitive status at baseline, >1 g/day DHA/EPA significantly improved episodic memory of subjects with mild memory complaints [p 0.04].

The investigators found there was a trend for episodic memory improvement in response to supplementation in subjects 45 years or older [p 0.058].

The investigators found DHA intake above the mean DHA level studied (580 mg/day) significantly improved episodic memory in all subjects [p 0.009] and in subjects with mild memory complaints [p 0.019]. Significant means that there is an association with a 95% confidence.

The investigators found observational studies supported a beneficial association between intake/blood levels of DHA/EPA and memory function in older adults.

The investigators concluded DHA (>580 mg/day), alone or combined with EPA (>1 g/day DHA/EPA), contributes to improved memory function in older adults (45 years or older) with mild memory complaints.

Original title:
Docosahexaenoic Acid and Adult Memory: A Systematic Review and Meta-Analysis by Yurko-Mauro K, Alexander DD and Van Elswyk ME.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4364972/

Additional information of El Mondo:
Find more studies/information on elderly and EPA&DHA.

This meal provides at least 580 mg DHA.
1 g/day DHA/EPA corresponds to meals providing 4 days of DHA&EPA.

Episodic memory is the type of long-term, declarative memory in which we store memories of personal experiences that are tied to particular times and places.
Some examples of episodic memory:

• Your skiing vacation last winter;
• The first time you traveled by airplane;
• Your first high school day.

Objectives:
What is the impact of antioxidants (N-acetylcysteine (NAC), polyunsaturated fatty acids (PUFAs) and vitamins) on incidence of postoperative atrial fibrillation (POAF) and duration of length of hospital stay?

Study design:
This review article included 23 RCTs that reported outcomes of 4278 patients undergoing cardiac surgery.
A total of 10 RCTs with 1,026 patients (513 cases were allocated to the NAC and 513 cases to the control group, with a mean age of 63.2 years and 76.8% being males), 8 RCTs with 2,687 patients (with a mean age of 64.17 years and 77.6% being males), and 5 RCTs with 565 patients (with a mean age of 65.17 years and 73.6% being males) investigated the effect of NAC, PUFA and antioxidant vitamins on POAF, respectively.

There was no publication bias.

Results and conclusions:
The investigators found pooled effects estimates on postoperative atrial fibrillation showed a significant reduction after:
NAC [OR = 0.56, 95% CI = 0.40-0.77, p 0.001, I2 = 15%, p = 0.3];
PUFA [OR = 0.84, 95% CI = 0.71-0.99, p = 0.03] and;
Vitamin C treatment [OR = 0.50, 95% CI = 0.27-0.91, p = 0.02, I2 = 50%].

The investigators found hospital length of stay was not significant reduced after NAC therapy [SMD = 0.082, 95% CI = -0.09 to 0.25, p = 0.3, I2 = 0.0%, p = 0.7], but could be significant decreased with PUFA [SMD = -0.185, 95% CI = -0.35 to -0.018, p = 0.03, I2 = 11%, p = 0.3] and vitamin C [SMD = -0.325, 95% CI = -0.50 to -0.14, p 0.01, I2 = 60.4%, p = 0.056].
Significant because the p-values were less than the p-value of 0.05.

The investigators concluded perioperative antioxidant supplementations with N-acetylcysteine, polyunsaturated fatty acids and vitamin C prevent atrial fibrillation after cardiac surgery. Moreover, polyunsaturated fatty acids and vitamin C are capable to reduce hospital stay, whereas N-acetylcysteine lacks this capacity.

Original title:
Antioxidant supplementations for prevention of atrial fibrillation after cardiac surgery: an updated comprehensive systematic review and meta-analysis of 23 randomized controlled trials by Ali-Hassan-Sayegha S, Mirhosseinia SJ, […], Liakopoulose OJ.

Link:
http://icvts.oxfordjournals.org/content/early/2014/02/19/icvts.ivu020.long

Additional information of El Mondo:
Find more studies on cardiovascular diseases, antioxidants, NAC, PUFA, vitamin C and p-value of 0.05/95% CI right here.