Nutrition and health

Objectives:
Previous studies suggest that dietary vitamin C is inversely associated with gastric cancer (GC), but most of them did not consider intake of fruit and vegetables. Therefore, this review article has been conducted.

Do higher dietary vitamin C intakes reduce gastric cancer risk after adjusting for intake of fruit and vegetables?

Study design:
This review article included 14 case-control studies with in total 5,362 cases (persons with gastric cancer) and 11,497 controls (persons without gastric cancer).

More cases were male (61.88% vs. 54.64%), older than 60 years (63.37% vs. 57.87%) and had low socioeconomic status (57.29% vs. 45.66%) compared with controls. 
In addition, a higher proportion of cases than controls were obese (21.34% vs. 19.06%), current smokers (26.58% vs. 24.14%) and ever drinkers (64.85 vs. 63.29%). 
Similarly, H. pylori seropositivity (63.82% vs. 61.86%) was more common among cases than among controls when considering only participants from the 7 studies with available information. 
A larger proportion of controls reported high intake of fruit and vegetables compared with cases. 
Most cases were of noncardia (57.03%) and intestinal type gastric cancer (33.01%). 
Cases had a lower median intake of vitamin C and fewer of them were in the highest quartiles of intake compared with controls.

Results and conclusions:
The investigators found individuals in the highest quartile of dietary vitamin C intake had a significantly reduced risk of 36% for gastric cancer compared with those in the lowest quartile [OR = 0.64, 95% CI = 0.58 to 0.72]. 

The investigators found, however, when additionally adjusting for BMI and intake of fruit and vegetables, the observed association was attenuated and the OR for the highest versus lowest quartile of dietary vitamin C was 0.85 [95% CI = 0.73 to 0.98].

The investigators found a significant inverse association for noncardia gastric cancer, as well as for both intestinal and diffuse types of the disease. 

The investigators found dose-response analysis showed decreasing ORs of gastric cancer up to 150-200 mg/day of vitamin C [OR = 0.54, 95% CI = 0.41 to 0.71], whereas ORs for higher intakes were close to 1.0. 

The investigators concluded that consumption of 150-200 mg/day of vitamin C reduce gastric cancer risk. However, further well-designed prospective studies, aimed at disentangling the complex relationships between intake of fruit and vegetables, vitamins and other antioxidants and gastric cancer, are warranted to prove causality of the observed relationship between vitamin C and gastric cancer.

Original title: 
Dietary intake of vitamin C and gastric cancer: a pooled analysis within the Stomach cancer Pooling (StoP) Project by Sassano M, Seyyedsalehi  MS, […], Boffetta P. 

 

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11016516/

Additional information of El Mondo:
Find more information/studies on cohort studies/significantly, viamin C and cancer right here. 

Objectives:
The association between soy product consumption and cancer risk varies among studies. Therefore, this review article has been conducted.

Do higher soy product consumption reduce cancer risk?

Study design:
This review article included 17 cohort studies and 35 case-control studies with a total of 861,372 participants and 44,932 cases (persons with cancer). 

Regarding quality assessment, the case-control studies achieved an average score of 6.7. The mean score of the cohort study was 7.2, which satisfied the criterion of high quality. 
All analyses adjusted for age and most studies adjusted for smoking status (n = 38), drinking status (n = 29), total energy intake (n = 27), BMI (n = 26) and education level (n = 26). 

Results and conclusions:
The investigators found in pooled analysis of cohort studies and case-control studies that higher consumption of total soy products significantly reduced risk of cancer with 31% [RR = 0.69, 95% CI = 0.60 to 0.80, I2 = 82.7%, p < 0.001]. 
However, this reduced risk was not significant in cohort studies (RR = 0.90, 95% CI = 0.80 to 1.01].

The investigators found higher tofu consumption significantly reduced cancer risk in both men and women.

The investigators found higher consumption of total soy products significantly reduced risk of cancer amond women with 24% [RR = 0.76, 95% CI = 0.65 to 0.89].

The investigators found in subgroup analysis that higher consumption of total soy products was significantly associated with a reduced risk for gastrointestinal cancer [RR = 0.74, 95% CI = 0.61 to 0.89], prostate cancer [RR = 0.47, 95% CI = 0.31 to 0.71], lung cancer [RR = 0.67, 95% CI = 0.52 to 0.86], upper aerodigestive tract cancer [RR = 0.33, 95% CI = 0.22 to 0.49] and multiple myeloma [RR = 0.10, 95% CI = 0.01 to 0.97], but not in bladder or liver cancer.

The investigators found in pooled analysis of cohort studies and case-control studies that higher consumption of tofu significantly reduced risk of cancer with 22% [RR = 0.78, 95% CI = 0.70 to 0.86, I2 = 47.9%, p = 0.004]. 
However, this reduced risk was not significant in cohort studies [RR = 0.89, 95% CI = 0.78 to 1.01, p = 0.186].

The investigators found in pooled analysis of cohort studies and case-control studies that higher consumption of soymilk significantly reduced risk of cancer with 25% [RR = 0.75, 95% CI = 0.60 to 0.86, I2 = 47.9%, p = 0.004]. 
However, this reduced risk was not significant in cohort studies [RR = 1.10, 95% CI = 0.76 to 1.58].

The investigators found a 54g per day increment of total soy products significantly reduced cancer risk by 11%, a 61g per day increment of tofu significantly reduced cancer risk by 12%, and a 23g per day increment of soymilk significantly reduced cancer risk by 28%, while none of the other soy products were associated with cancer risk. 

The investigators concluded that daily consumption of 54g total soy products, 61g tofu or 23g soymilk is associated with a lower cancer risk. More prospective cohort studies are still needed to confirm the causal relationship between soy product consumption and cancer risk.

Original title: 
Soy Product Consumption and the Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies by Wang C, Ding K, […], Hong H. 

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11013307/

Additional information of El Mondo:
Find more information/studies on cohort studies/significantly, soy and cancer right here. 

Objectives:
Carotenoids appear to have anticancer effects. Prospective evidence for the relation between serum carotenoids and breast cancer is controversial. Therefore, this review article has been conducted.

Do higher carotenoids levels (likes, α-carotene, β-carotene, β-cryptoxanthin, lycopene, zeaxanthin and lutein) reduce breast cancer risk among women?

Study design:
This review article included 17 nested case-control studies and 1 cohort study, published between 1984 and 2016 with a total of 20,188 participants. 
Median follow-up ranged from 8 months to 21 years during which 7,608 breast cancer cases were reported. 
All studies assessed circulating carotenoids using high-performance liquid chromatography. The majority of studies carried out on circulating carotenoids and the risk of breast cancer were adjusted for the following variables: BMI (n = 9), dietary variables (n = 8), age (n = 9), alcohol (n = 6), age at menarche (n = 6) and age at first birth (n = 8). 
According to the quality assessment, except for 2 studies, other publications had high quality. 

There was no publication bias. 

Results and conclusions:
The investigators found that the highest levels of total carotenoids compared to the lowest were significantly related to a 24% lower risk of breast cancer [relative risk (RR) = 0.76, 95% CI = 0.62 to 0.93, I2 = 45.6%, p = 0.075]. 
According to the sensitivity analysis, no study affected the overall RR. 

The investigators found according to linear dose-response analysis, the risk of breast cancer decreased by 2% for every 10 μg/dL of total carotenoids [RR = 0.98, 95% CI = 0.97 to 0.99]. A steady drop in the risk of breast cancer was observed for total carotenoid concentrations <1200 μg/dL followed by a plateau. The level of evidence was graded as low.

The investigators found that the highest levels of α-carotene compared to the lowest were significantly related to a 23% lower risk of breast cancer [relative risk (RR) = 0.77, 95% CI = 0.68 to 0.87, I2 = 0.0%, p = 0.48]. 
According to the sensitivity analysis, no study affected the overall RR. 

The investigators found according to linear dose-response analysis, the risk of breast cancer decreased by 22% for every 10 μg/dL of α-carotene [RR = 0.78, 95% CI = 0.66 to 0.93]. 
No evidence for nonlinear association was found. The level of evidence was graded as low. 

The investigators found that the highest levels of β-carotene compared to the lowest were significantly related to a 20% lower risk of breast cancer [relative risk (RR) = 0.80, 95% CI = 0.65 to 0.98, I2 = 56.5%, p = 0.004]. 
According to the sensitivity analysis, no study affected the overall RR. 

The investigators found according to linear dose-response analysis, the risk of breast cancer decreased by 4% for every 10 μg/dL of β-carotene [RR = 0.96, 95% CI = 0.93 to 0.99]. No evidence for nonlinear association was found. The level of evidence was graded as low. 

The investigators found that the highest levels of β-cryptoxanthin compared to the lowest were significantly related to a 15% lower risk of breast cancer [relative risk (RR) = 0.85, 95% CI = 0.74 to 0.96, I2 = 0.0%, p = 0.80]. 
According to the sensitivity analysis, no study affected the overall RR. 

The investigators found according to linear dose-response analysis, the risk of breast cancer decreased by 10% for every 10 μg/dL of β-cryptoxanthin [RR = 0.90, 95% CI = 0.82 to 0.99]. 

The investigators found that the highest levels of lycopene compared to the lowest were significantly related to a 14% lower risk of breast cancer [relative risk (RR) = 0.86, 95% CI = 0.76 to 0.98, I2 = 0.0%, p = 0.46]. 
According to the sensitivity analysis, no study affected the overall RR. 

The investigators found that the highest levels of lutein compared to the lowest were significantly related to a 30% lower risk of breast cancer [relative risk (RR) = 0.70, 95% CI = 0.52 to 0.93, I2 = 17.1%, p = 0.30]. 
According to the sensitivity analysis, no study affected the overall RR. 

The investigators concluded that higher levels of carotenoids, α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein are related to a decreased risk of breast cancer. Additionally, each 10 μg/dL of total carotenoids, α-carotene, β-carotene and β-cryptoxanthin reduce breast cancer risk with 2%, 22%, 4% and 10%, respectively. 

Original title: 
The Association between Circulating Carotenoids and Risk of Breast Cancer: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies by Dehnavi MK, Ebrahimpour-Koujan S, […], Azadbakht L.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10694674/ 

Additional information of El Mondo:
Find more information/studies on cohort studies/significantly, carotenoids and breast cancer right here. 

Objectives:
Does consumption of fruits and vegetables reduce risk of endometrial cancer?

Study design:
This review article included  of 21 case-control studies and 6 cohort studies.

Results and conclusions:
The investigators found that vegetables consumption significantly reduced risk of endometrial cancer with 24% [pooled odds ratio [OR], relative risk [RR], hazard ratio [HR] = 0.76, 95% CI = 0.63 to 0.91].

The investigators found that cruciferous vegetables consumption significantly reduced risk of endometrial cancer with 19% [pooled OR = 0.81, 95% CI = 0.70 to 0.94].

The investigators found that dark green and yellow/orange combined vegetables consumption significantly reduced risk of endometrial cancer with 36% [pooled OR = 0.64, 95% CI = 0.42 to 0.97].

The investigators found that fruits consumption significantly reduced risk of endometrial cancer with 19% [pooled OR = 0.81, 95% CI = 0.70 to 0.92].

The investigators found these results were primarily based on studies of high quality and exhibited either by case-control only or a combination of case-control and cohort studies. Additionally, the results varied by geographic location, such as Western areas, the US and Italy.

The investigators concluded that consumption of fruits and vegetables has beneficial effects on endometrial cancer risk and that specific kinds of fruits and vegetables should be recommended differently due to their outstanding bioactive components.

Original title:
The influence of dietary vegetables and fruits on endometrial cancer risk: a meta-analysis of observational studies by Lu YT, Gunathilake M and Kim J.

Link:
https://pubmed.ncbi.nlm.nih.gov/36151331/

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

Objectives:
There is keen interest in better understanding the impacts of alpha-linolenic acid (ALA), a plant-derived n-3 fatty acid, in ameliorating the development of cancer. However, results of several prospective cohort studies present an inconsistent association between ALA intake and the incident colorectal cancer (CRC). Therefore, this review article has been conducted.

Does a high dietary intake of alpha-linolenic acid or a high level of alpha-linolenic acid in blood reduce risk of colorectal cancer (colon and rectal cancer)?

Study design:
This review article included 15 cohort studies (11 studies on diet and 5 studies on biomarkers including 4 on blood and 1 on adipose tissue) with 12,239 colorectal cancer cases occurred among 861,725 participants.
The mean follow-up was 9.3 years (ranging from 1 to 28 years).
Among all of the included studies, quality scores assessed by the 9-star NOS ranged from 7 to 9, with a median quality (≤7 stars) in 2 studies and high quality (≥ 8 stars) in 13 studies.

There was no publication bias.

Results and conclusions:
The investigators found higher level of alpha-linolenic acid in blood significantly reduced risk of colorectal cancer with 17% [summary RR = 0.83, 95% CI = 0.69 to 0.99, I2 = 0.0%].

The investigators found each 0.1% increase in the level of alpha-linolenic acid in blood was significantly associated with a 10% reduction in colorectal cancer risk [summary RR = 0.90, 95% CI = 0.80 to 0.99, I2 = 38.6%].

The investigators no significant dose-response association between dietary intake of alpha-linolenic acid and the incident colorectal cancer [p for non-linearity = 0.18; p for linearity = 0.24].

The investigators concluded that higher blood levels of alpha-linolenic acid reduce risk of colorectal cancer while higher dietary intake of alpha-linolenic acid does not reduce risk of colorectal cancer. Encouraging the consumption of foods rich in alpha-linolenic acid to improve its levels in the blood may potentially decrease the risk of colorectal cancer. Nevertheless, well-designed and large-scale cohort studies with biomarkers are still needed for better reconfirming the potential impacts of alpha-linolenic acid intake in the primary prevention of colorectal cancer.

Original title:
Association of Dietary Intake and Biomarker of α-Linolenic Acid With Incident Colorectal Cancer: A Dose-Response Meta-Analysis of Prospective Cohort Studies by Dai ZB, Ren XL, […], Xu L.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9301188/

Additional information of El Mondo:
Find more information/studies on colorectal cancer and alpha-linolenic acid consumption right here.

Objectives:
Colorectal cancer is one of the most commonly diagnosed and deadly cancers worldwide. Epidemiological studies on the relationship between folate intake and the risk of colorectal cancer have reported inconsistent findings since folate fortification in the USA. Therefore, this review article has been conducted.

Does a high folate (folic acid) ietary intake reduce risk of colorectal cancer (colon and rectal cancer)?

Study design:
This review article included 24 cohort studies involving 6,165,894 individuals, of which 37,280 persons with colorectal cancer.

Results and conclusions:
The investigators found compared with the lowest dietary intake, the highest folate dietary intake significantly reduced risk of colorectal cancer with 12% [combined relative risk (RR) = 0.88, 95% CI = 0.83 to 0.92, p = 0.0004].
Significantly means that there is an association with a 95% confidence.

The investigators found compared with the lowest dietary intake, the highest folate dietary intake significantly reduced risk of colorectal cancer with 3% among persons witih medium alcohol consumption [RR = 0.97, 95% CI = 0.96 to 0.99, p = 0.008].
Significantly because RR of 1 was not found in the 95% CI of 0.96 to 0.99. RR of 1 means no risk/association.

The investigators found compared with the lowest dietary intake, the highest folate dietary intake significantly reduced risk of colorectal cancer with 5% among persons witih high alcohol consumption [RR = 0.95, 95% CI = 0.92 to 0.97, p = 0.003].

The investigators found compared with the lowest dietary intake, the highest folate dietary intake did not reduce risk of colorectal cancer among non-drinkers [RR = 1.00, 95% CI = 0.98 to 1.02, p = 0.827].

The investigators found compared with the lowest dietary intake, the highest folate dietary intake significantly reduced risk of colon cancer with 14% [RR = 0.86, 95% CI = 0.81 to 0.92, p = 0.0004].
Significantly because the calculated p-value of 0.0004 was less than the p-value of 0.05.

The investigators found compared with the lowest dietary intake, the highest folate dietary intake did not reduce risk of rectal cancer [RR = 0.92, 95% CI = 0.84 to 1.02, p = 0.112].

The investigators found compared with the lowest dietary intake, the highest folate dietary intake significantly reduced risk of colorectal cancer in USA and Europe but not in other regions.

The investigators concluded that high folate dietary intake reduces risk of colon cancer, particularly in people with medium or high alcohol consumption, but it still needs to be further confirmed.

Original title:
Folate intake and risk of colorectal cancer: a systematic review and up-to-date meta-analysis of prospective studies by Fu H, He J, […], Chang H.

Link:
https://pubmed.ncbi.nlm.nih.gov/35579178/

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

Colorectal cancer starts in the colon or the rectum. These cancers can also be called colon cancer or rectal cancer, depending on where they start.

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

Does a higher dietary intake of meat increases the risk of hepatocellular carcinoma?

Study design:
This review article included 17 observational studies involving 2,915,680 participants, of which 4,953 cases of hepatocellular carcinoma.

10 studies reported red meat intake, 9 reported white meat intake, 9 reported fish intake, 7 reported processed meat intake and 5 reported total meat intake.

Results and conclusions:
The investigators found results showed that the consumption of red meat [relative risk = 1.04, 95% CI = 0.91 to 1.18, I2 = 50.50%, p = 0.033] and total meat intake [relative risk = 1.01, 95% CI =  0.90 to 1.13, I2 = 15.50%, p = 0.316] were not significantly associated with risk of hepatocellular carcinoma.

The investigators found, however, a higher dietary intake of processed meat significantly increased the risk of hepatocellular carcinoma with 20% [relative risk = 1.20, 95% CI = 1.02 to 1.41, I2 = 26.30%, p = 0.228].
Significant because relative risk of 1 was not found in the 95% CI of 1.02 to 1.41. Relative risk of 1 means no risk/association.

The investigators found, in contrast, a higher dietary intake of white meat significantly decreased the risk of hepatocellular carcinoma with 24% [relative risk = 0.76, 95% CI = 0.63 to 0.92, I2 = 68.30%, p = 0.001].

The investigators found, in contrast, a higher dietary intake of fish significantly decreased the risk of hepatocellular carcinoma with 9% [relative risk = 0.91, 95% CI = 0.86 to 0.96, I2 = 40.90%, p = 0.095].

The investigators concluded that a higher dietary intake of processed meat increases the risk of hepatocellular carcinoma, while a higher dietary intake of both white meat and fish decrease the risk of hepatocellular carcinoma. Therefore, these findings suggest that dietary intervention may be an effective approach to preventing hepatocellular carcinoma. These need to be verified with further well-designed observational studies and experimental clinical research.  

Original title:
Meat Intake and the Risk of Hepatocellular Carcinoma: A Meta-Analysis of Observational Studies by Yu J, Liu Z, […], Chen W.

Link:
https://pubmed.ncbi.nlm.nih.gov/35583453/

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

Processed meats are meats that have been preserved by smoking or salting, curing or adding chemical preservatives. They include deli meats, bacon and hot dogs.

Objectives:
Evidence associating diet with the incidence of renal cell carcinoma (RCC) is inconclusive. Therefore, this umbrella review article has been conducted.

What is the association between diet and renal cell carcinoma incidence?

Study design:
This umbrella review article included 22 meta-analyses with a total of 502 individual studies and 64 summary hazard ratios (HRs) for renal cell carcinoma incidence: dietary patterns or dietary quality indices (n = 6), foods (n = 13), beverages (n = 4), alcohol (n = 7), macronutrients (n =15) and micronutrients (n =19).

No meta-analyses had high methodological quality.

59% of these 502 individual studies were cohort studies (n = 298), 39% were case-control studies (n = 196) and 2% were pooled studies (n = 8).

Sixty (94%) exposures in the included meta-analyses had more than 1,000 cases or 20,000 participants.

Results and conclusions:
The investigators found no dietary factors showed convincing or highly suggestive evidence of association with renal cell carcinoma incidence in the overall analysis.

The investigators found in the overall analysis that dietary intake of vegetables significantly reduced risk of renal cell carcinoma with 26% [summary HR = 0.74, 95% = 0.63 to 0.86, suggestive evidence].

The investigators found in the overall analysis that dietary intake of vitamin C significantly reduced risk of renal cell carcinoma with 23% [summary HR = 0.77, 95% = 0.66 to 0.90, suggestive evidence].

The investigators found in the overall analysis that moderate drinking significantly reduced risk of renal cell carcinoma with 23% [summary HR = 0.77, 95% = 0.70 to 0.84, convincing evidence] in Europe and North America.

The investigators found in the overall analysis that dietary intake cruciferous vegetables significantly reduced risk of renal cell carcinoma with 22% [summary HR = 0.78, 95% = 0.70 to 0.86, highly suggestive evidence] in North America.

The investigators concluded dietary intake of vegetables and vitamin C could reduce renal cell carcinoma risk. Moderate drinking might be beneficial for Europeans and North Americans and cruciferous vegetables might be beneficial to North Americans, but the results should be interpreted with caution because no meta-analyses had high methodological quality. More researches are needed in the future.

Original title:
The role of diet in renal cell carcinoma incidence: an umbrella review of meta-analyses of observational studies by Liao Z, Fang Z, […], Luo Z.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8812002/

Additional information of El Mondo:
Find more information/studies on cancer, vegetables, vitamin C right here.

An umbrella review article is a scientific article which only includes meta-analyses (also called review articles). The results found in an umbrella review article are more reliable than found in an individual review article.

One swallow does not make a summer. A famous Dutch saying that could not be any more obvious. Just because one single scientific study about a certain topic makes certain claims, it does not necessarily mean it is true. On the other hand, a review article (a collection of scientific studies on a certain topic) of randomized, placebo-controlled double blind clinical trials (RCTs) will answer the following question:
"Do taking dietary supplements make sense?" Yes for a positive conclusion and no for a negative conclusion.

One swallow does not make a summer. A famous Dutch saying that could not be any more obvious. Just because one single scientific study about a certain topic makes certain claims, it does not necessarily mean it is true. On the other hand, a review article (a collection of scientific studies on a certain topic) of (prospective) cohort studies or case-control studies will answer the following question:
"Should I change my diet?".

Objectives:
Does a high olive oil consumption reduce cancer risk?

Study design:
This review article included 37 case-control studies with 17,369 cases (persons with cancer) and 28,294 controls (persons without cancer) and 8 cohort studies with 12,461 incident cases among 929,771 subjects (participants).

Significant publication bias was detected via Egger’s test in the analysis on overall cancer risk [p 0.001], breast cancer [p = 0.013] and gastrointestinal cancer risk [p = 0.048].

Results and conclusions:
The investigators found in pooled analysis of case-control and cohort studies that highest olive oil consumption was significantly associated with a 31% lower risk of any cancer [pooled RR = 0.69, 95% CI = 0.62 to 0.77].  
Significantly means that there is an association with a 95% confidence.

The investigators found subgroup analyses showed that the protective effect of high olive oil consumption in terms of cancer risk was also significant in case-control studies [37 study arms, RR = 0.65, 95% CI = 0.57 to 0.74] but not in cohort studies [8 study arms, RR = 0.90, 95% CI = 0.77 to 1.05].
Furthermore, the protective association was also found in a multivariate analysis [32 study arms, RR = 0.72, 95% CI = 0.65 to 0.81], a high study quality analysis [RR = 0.72, 95% CI = 0.64 to 0.81], Mediterranean participants [RR = 0.69, 95% CI = 0.60 to 0.79] and non-Mediterranean participants [RR = 0.49, 95% CI = 0.34 to 0.71].

The investigators found in pooled analysis of case-control and cohort studies that highest olive oil consumption was significantly associated with a 33% lower risk of breast cancer [pooled RR = 0.67, 95% CI = 0.52 to 0.86].  
Significantly because RR of 1 was not found in the 95% CI of 0.52 to 0.86. RR of 1 means no risk/association.

The investigators found subgroup analyses showed that the beneficial effect was reproducible in case-control studies [RR = 0.63, 95% CI = 0.45 to 0.87] but not in cohort studies.
Furthermore, high olive oil consumption was linked to a reduced breast cancer risk in Mediterranean [RR = 0.67, 95% CI = 0.49 to 0.92] and non-Mediterranean populations [RR = 0.25, 95% CI = 0.07 to 0.89].

The investigators found in pooled analysis of case-control and cohort studies that highest olive oil consumption was significantly associated with a 23% lower risk of gastrointestinal cancer [pooled RR = 0.77, 95% CI = 0.66 to 0.89].  
Subgroup analyses showed an inverse relationship between highest olive oil consumption and risk for esophageal cancer [RR = 0.47, 95%CI = 0.24 to 0.93] and pancreatic cancer [RR = 0.58, 95% CI = 0.35 to 0.97].
Furthermore, significant effects were also found in case-control studies [RR = 0.72, 95% CI = 0.61 to 0.85), studies within the Mediterranean area [RR = 0.77, 95% CI = 0.67 to 0.88], multivariate analyses [RR = 0.76, 95% CI = 0.63 to 0.90] and high quality studies [RR = 0.73, 95% CI = 0.62 to 0.86].

The investigators found in pooled analysis of case-control and cohort studies that highest olive oil consumption was significantly associated with a 26% lower risk of upper aerodigestive cancer [pooled RR = 0.74, 95% CI = 0.60 to 0.91].  
Subgroup analyses showed results remained significant for case-control studies [RR = 0.74, 95% CI = 0.60 to 0.91], multivariate analyses [RR = 0.75, 95% CI = 0.66 to 0.86] and studies of high quality [RR = 0.68, 95% CI = 0.52 to 0.89].

The investigators found in pooled analysis of case-control studies that highest olive oil consumption was significantly associated with a 54% lower risk of urinary tract cancer [pooled RR = 0.46, 95% CI = 0.29 to 0.72].  
Subgroup analyses showed results remained significant for studies of high quality [RR = 0.46, 95% CI = 0.32 to 0.66].

The investigators concluded highest versus lowest olive oil consumption is associated with 31% lower cancer risk, especially for breast, overall gastrointestinal, upper aerodigestive and urinary tract cancer. Additional prospective cohort studies on various cancer types, especially in non-Mediterranean regions, as well as large randomized trials, seem desirable in order to provide further insight into the role of olive oil in preventing cancer.

Original title:
Olive oil intake and cancer risk: A systematic review and meta-analysis by Markellos C, Ourailidou ME, […], Psaltopoulout T.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8751986/

Additional information of El Mondo:
Find more information/studies on cancer, olive oil consumption right here.

The conclusions in scientific studies are even more reliable when they are also found in cohort studies, multivariate analyzes (studies where adjustments were made for multiple confounding factors) and high-quality studies.
 

Objectives:
Does postoperative coffee or caffeine consumption causally reduce risk of postoperative ileus (POI) in patients undergoing elective colorectal surgery?

Study design:
This review article included 4 RCTs with 312 subjects.

Results and conclusions:
The investigators found postoperative coffee or caffeine consumption significantly decreased the time to first bowel movement [MD = -10.36 h, 95% CI = -14.61 to -6.11], shortened the length of hospital stay [MD = -0.95 days, 95% CI = -1.57 to -0.34] and was significantly  associated with a 36%-decreased risk of the use of any laxatives after the procedure [RR = 0.64, 95% CI = 0.44 to 0.92].

The investigators found the time to first flatus, time to tolerance of solid food, risk of any postoperative complication, postoperative reinsertion of a nasogastric (NG) tube and anastomotic leakage showed no statistical differences between groups.

The investigators concluded postoperative coffee or caffeine consumption causally improves bowel movement and decreases the duration of hospital stay in patients undergoing elective colorectal surgery. This method is safe and can prevent or treat postoperative ileus (POI).

Original title:
The effect of coffee/caffeine on postoperative ileus following elective colorectal surgery: a meta-analysis of randomized controlled trials by Yang TW, Wang CT, […], Tsai MC.

Link:
https://pubmed.ncbi.nlm.nih.gov/34993568/

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

Postoperative ileus is a prolonged absence of bowel function after surgical procedures, usually abdominal surgery.