Nutrition and health

Objectives:
Taurine plays a pivotal role in regulating glucose and lipid metabolism, blood pressure homeostasis and obesity largely due to its cytoprotective, antioxidant and anti-inflammatory actions. Despite promising data from animal studies in this scenario, the efficacy of taurine supplementation in human studies has been inconsistent. Therefore, this review article has been conducted.

Does taurine supplementation lower blood pressure and improve the lipid profile in patients with liver dysregulation?

Study design:
This review article included 12 RCTs.
Most studies were conducted in patients with liver or metabolic dysregulation (diabetes, hepatitis, fatty liver, obesity, cystic fibrosis, chronic alcoholism and cardiac surgery).
The taurine dosage varied from 0.5 to 6 g/d for 15 days to 6 months.

Results and conclusions:
The investigators found that taurine administration (supplementation) had a significant effect of on systolic blood pressure [WMD = -4.67 mm Hg, 95% CI = -9.10 to -0.25], diastolic blood pressure [WMD = -2.90 mm Hg, 95% CI = -4.29 to -1.52], total cholesterol levels [WMD = -10.87 mg/dL, 95% CI = -16.96 to -4.79] and triglycerides levels [WMD = -13.05 mg/dL, 95% CI = -25.88 to -0.22]. 

The investigators found, however, that taurine administration had no effect on fasting blood glucose [WMD = 0.06 mg/dL], HDL cholesterol [WMD = 0.90 mg/dL], LDL cholesterol [WMD = -6.17 mg/dL], as well as on body mass index [WMD = -0.46 kg/m²] and body weight [WMD = -0.47 kg] as the anthropometric measures.

The investigators concluded that, in patients with liver dysregulation, taurine supplements (0.5 to 6 g/d for 15 days to 6 months) reduce blood pressure and improve the lipid profile by reducing total cholesterol and triglyceride levels.

Original title:
The effects of taurine supplementation on obesity, blood pressure and lipid profile: A meta-analysis of randomized controlled trials by Guan L and Miao P.

Link:
https://pubmed.ncbi.nlm.nih.gov/32871172/

Additional information of El Mondo:
Find here more information/studies about taurine consumption and lowering blood pressure and cholesterol levels.

The main sources of taurine are animal foods, such as meat, fish and dairy products.

Objectives:
A dietary protein intake (DPI) of between 0.6 and 0.8 g protein per kilogram body weight per day (g/kg/day) is frequently recommended for adults with moderate-to-advanced chronic kidney disease (CKD). However, evidence on whether patients with diabetic kidney disease (DKD) actually benefit from a DPI of ≤ 0.8 g/kg/day and from a low-protein diet (LPD) at CKD stages 1-3 has not been consistent. Therefore, this review article has been conducted.

Do patients with diabetic kidney disease benefit from a dietary protein intake of 0.8 g protein per kilogram body weight per day (g/kg/day)?

Study design:
This review article included 9 RCTs with a total of 506 participants and follow-up periods varying from 4.5 to 60 months.

Results and conclusions:
The investigators found that patients with diabetic kidney disease who consumed 0.8 g protein/kg/day had a significantly reduced decline in glomerular filtration rate (GFR) [MD = 22.31 mL/min/1.73 m², 95% CI = 17.19 to 27.42, p 0.01] and a significant decrease in proteinuria [SMD = -2.26 units, 95% CI = -2.99 to -1.52, p 0.001] versus those on the control diet.

The investigators found the benefits of a low-protein diet to patients with diabetic kidney disease at chronic kidney disease stages 1-3 were a markedly decreased proteinuria [SMD - 0.96 units, 95% CI = -1.81 to -0.11, p = 0.03] and slight but significant decreases in glycated hemoglobin [-0.42%] and cholesterol levels [-0.22 mmol/L].

The investigators concluded that a dietary protein intake of 0.8 g/kg/day is strongly associated with a slow decline in glomerular filtration rate (GFR) and decreases proteinuria in the patients with diabetic kidney disease. Patients with chronic kidney disease (CKD) stages chronic kidney disease 1-3 benefit from a low-protein diet in terms of a marked decrease of proteinuria and slight but significant improvements in lipid and glucose control.  

Original title:
Diabetic Kidney Disease Benefits from Intensive Low-Protein Diet: Updated Systematic Review and Meta-analysis by Li Q, Wen F, [...], Wang W.

Link:
https://pubmed.ncbi.nlm.nih.gov/33150563/

Additional information of El Mondo:
Find here more information/studies about protein consumption and kidney disease.

For example: you are a patient with diabetic kidney disease, you weigh 70 kg and you want to eat 2200 kcal every day. How should you meet a dietary protein intake of 0.8 g protein per kilogram body weight per day (g/kg/day) in daily life?
Every day you should take maximal 0.8 g protein x 70 kg = 56 g protein. 56 g protein give 56x4 kcal = 224 kcal. 224 kcal is around 10% of 2200 kcal. Thus, you should eat products whose protein content contributes maximum 10% to the total kcal of the product in question, meaning you should eat products with 10 En% protein. These products in the supermarket contain maximum 10 En% protein.

Thus, a dietary protein intake of 0.8 g protein per kilogram body weight per day (g/kg/day) for a person weighing 70 kg on a diet of 2200 kcal, means he/she should eat products with maximum 10 En% protein in daily life.
 

Objectives:
Soy products contain several compounds with anti-inflammatory properties like genistein and daidzein which reported to act through different pathways. However, there are inconsistent results and lack of any comprehensive review regarding randomized controlled trials which assess the effect of soy products on inflammatory markers. Therefore, this review article has been conducted.

Does soy product supplementation reduce levels of inflammatory markers, like CRP, IL-6?

Study design:
This review article included 51 RCTs.

Results and conclusions:
The investigators found soy product supplementation significantly reduced CRP levels [MD = -0.27 mg/L, 95% CI = -0.51 to -0.02, p = 0.028] but it did not affect IL-6 [MD = 0.0 pg/mL, 95% CI = -0.06 to 0.06, p = 0.970] and TNF-α [MD = -0.04 pg/mL, 95% CI = -0.11 to 0.03, p = 0.252].

The investigators found subgroup analysis showed that soy supplementation had a significant impact on decreasing IL-6 and TNF-α levels when studies had a long-term intervention (≥12 weeks) and used low dose isoflavone (100 mg/day).

The investigators concluded there is a significant reduction in CRP levels after soy product supplementation.

Original title:
The effects of soy supplementation on inflammatory biomarkers: A systematic review and meta-analysis of randomized controlled trials by Asbaghi O, Yaghubi E, […], Ghaedi E.

Link:
https://pubmed.ncbi.nlm.nih.gov/32979840/

Additional information of El Mondo:
Find here more information/studies about soy consumption and chronic disease.

Objectives:
There is some inconclusive evidence for the role of fish consumption in susceptibility to multiple sclerosis (MS). Therefore, this review article has been conducted.

Does fish consumption reduce multiple sclerosis (MS)?

Study design:
This review article included 6 observational studies.

Results and conclusions:
The investigators found that the consumption of fish (at least 0.5 servings of fish per week) significantly decreased the risk of multiple sclerosis with 23% [OR = 0.77, 95% CI = 0.64 to 0.92, p-value = 0.004, I2 = 54.7%] compared with controls.

The investigators concluded that dietary intake of at least 0.5 servings of fish per week during adolescence and after reduce the risk of multiple sclerosis; however, further studies are required to prove this preventive effect.

Original title:
Dietary fish intake and the risk of multiple sclerosis: a systematic review and meta-analysis of observational studies by Rezaeizadeh H, Mohammadpour Z, […], Homayon IA.

Link:
https://pubmed.ncbi.nlm.nih.gov/32787642/

Additional information of El Mondo:
Find here more information/studies about fish consumption.

Objectives:
The relationship between dietary pattern and the risk of chronic obstructive pulmonary disease (COPD) has been described; however, the exclusive role of dietary factors remains controversial. Therefore, this review article has been conducted.

Does a dietary intake of fruits and vegetables, dietary fiber, fish, n-3 or n-6 fatty acids and antioxidant vitamins reduce risk of COPD in adults?

Study design:
This review article included 10 cohort, 6 case-control and 20 cross-sectional studies.

To assess usual dietary intake, 28 studies had used food frequency questionnaires (FFQ), of which 2 studies had used FFQ and a 24-hour recall, 3 studies had used the crosscheck dietary method, 1 study had assessed with only 24-hour recall and 1 study had used weighted household food records.

Results and conclusions:
The investigators found a significantly reduced risk of 26% [relative risk = 0.74, 95% CI = 0.65 to 0.85] for COPD for the highest fruit intake group compared with the lowest intake group.
This significantly reduced risk was 29% in cohort studies [RR = 0.71, 95% CI = 0.63 to 0.79, I2 = 0.0%].

The investigators found a significantly reduced risk of 47% [relative risk = 0.53, 95% CI = 0.39 to 0.74, I2 = 0.0%, p = 0.65] for COPD mortality for the highest fruit intake group compared with the lowest intake group.

The investigators found a significantly reduced risk of 35% [relative risk = 0.65, 95% CI = 0.55 to 0.78] for COPD for the highest dietary fiber intake group compared with the lowest intake group.
This significantly reduced risk was 39% in cohort studies [RR = 0.61, 95% CI = 0.54 to 0.68, I2 = 0.0%, p = 0.9].

The investigators found a significantly reduced risk of 29% [relative risk = 0.71, 95% CI = 0.58 to 0.85] for COPD for the highest fish intake group compared with the lowest intake group.

The investigators found a significantly reduced risk of 11% [relative risk = 0.89, 95% CI = 0.76 to 0.99] for COPD for the highest vitamin C dietary intake group compared with the lowest intake group.

The investigators found no association between the risk of COPD and the intake of vegetables, n-3 fatty acids, vitamin E and β-carotene.

The investigators concluded that a higher dietary intake of fruit, dietary fiber, fish and vitamine C reduce the risk of COPD in adults.

Original title:
Dietary Factors and Risk of Chronic Obstructive Pulmonary Disease: A Systemic Review and Meta-Analysis by Seyedrezazadeh E, Moghaddam MP, […], Kolahdooz F.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7309892/

Additional information of El Mondo:
Find here more information/studies about fruit, dietary fiber, fish and vitamine C.

Objectives:
Vitamin D deficiency has been related to the risk of sepsis. However, previous studies showed inconsistent results regarding the association between serum 25-hydroxyvitamin D (25 (OH)D) and mortality risk in septic patients. Therefore, this review article has been conducted.

Does a low serum 25-hydroxyvitamin D (vitamin D level in blood) increase mortality risk in septic patients?

Study design:
This review article included 8 follow-up studies (4 were prospective and the other 4 were retrospective) with 1,736 septic patients.

The sample sizes of the included studies varied from 57 to 610.
The mean ages of the patients included in each study ranged from 57 to 75 years and the proportions of male patients varied from 43% to 71%.

Optimal vitamin D level, vitamin D insufficiency, vitamin D deficiency and severe vitamin D deficiency are defined as serum 25 (OH)D > 30 ng/mL, 21-29 ng/mL and  20 ng/mL, 10 ng/mL, respectively.

There was no publication bias.

Results and conclusions:
The investigators found meta-analysis with a random-effect model showed that septic patients with lower serum 25 (OH)D ( 30 ng/ml) at admission was associated with a significantly increased mortality risk of 93% [adjusted RR = 1.93, 95% CI = 1.41 to 2.63, p  0.001, I2 = 63%, p = 0.003].
Sensitivity analysis by excluding one study at a time did not significantly change the results.

The investigators found subgroup analyses according to the severity of vitamin D deficiency showed that patients with severe vitamin D deficiency ( 10 ng/mL) was significantly associated with a 92% higher mortality risk [adjusted RR = 1.92, 95% CI = 1.09 to 2.55, p  0.001].
But the associations were not significant for vitamin D insufficiency (25 (OH)D = 20-30 ng/mL) or deficiency (25 (OH)D = 10-20 ng/mL).

The investigators found further analyses showed that the association between lower serum 25(OH) D and higher mortality risk were consistent in studies applied different diagnostic criteria for sepsis (SIRS, Sepsis-2.0 or Sepsis-3.0), short-term (within 1 month) and long-term studies (3-12 months) and in prospective and retrospective studies.

The investigators concluded that severe vitamin D deficiency ( 10 ng/mL) is independently associated with increased mortality in patients with sepsis. Large-scale prospective studies are needed to validate these findings.

Original title:
Serum 25-Hydroxyvitamin D and the risk of mortality in adult patients with Sepsis: a meta-analysis by Li Y and Ding S.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7057612/

Additional information of El Mondo:
Find here more information/studies about vitamin D.

Objectives:
Multiple sclerosis (MS) is a demyelinating and disabling inflammatory disease of the central nervous system. Multiple sclerosis is triggered by complex environmental factors which mostly affect genetically the susceptible young people. Emerging data has suggested that changes of homocysteine (Hcy), vitamin B12 and folate serum levels may be associated with multiple sclerosis. However, previous findings are not always consistent. Therefore, this review aricle has been conducted.

Does a low serum homocysteine, vitamin B12 or folate level increase risk of multiple sclerosis?

Study design:
This review article included 21 original studies with 1,738 multiple sclerosis patients and 1,424 controls (patients without multiple sclerosis). There were 17 studies for measuring homocysteine, 16 studies for measuring vitamin B12 and 13 studies for measuring folate in patients with multiple sclerosis, respectively.

Results and conclusions:
The investigators found patients with multiple sclerosis (MS) had higher serum levels of homocysteine [SMD = 0.64, 95% CI = 0.33 to 0.95, p 0.0001] compared with control groups.

The investigators found no significant differences of SMD for vitamin B12 [SMD = -0.08, 95% CI = -0.35 to 0.20, p = 0.58] or folate [SMD = 0.07, 95% CI = -0.14 to 0.28, p = 0.52] between MS and controls.

The investigators found subgroup analysis demonstrated that there was statistically significant difference for homocysteine between relapsing-remitting MS (RRMS) patients and controls with a SMD of 0.67 [95% CI = 0.21 to 1.13, p = 0.004].

However, no significant difference of homocysteine serum levels between secondary progressive MS patients or primary progressive MS patients and controls.

The investigators found no significant difference of homocysteine levels in females [SMD = 0.22, 95% CI = -0.16 to 0.60, p = 0.25] or males [SMD = 0.56, 95% CI = -0.13 to 1.26, p = 0.11] between MS patients and controls.

The investigators concluded higher serum levels of homocysteine increase risk of multiple sclerosis (MS), especially for relapsing-remitting MS (RRMS) patients. Functional studies are required to assess the effects of homocysteine on patients with MS at the molecular level.

Original title:
Serum levels of Homocysteine, Vitamin B12 and Folate in Patients with Multiple Sclerosis: an Updated Meta-Analysis by Li X, Yuan J, [...], Hu W.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7085269/

Additional information of El Mondo:
Find here more information/studies about lowering serum levels of homocysteine.

Objectives:
Physical exercise may offer multiple benefits to patients with chronic kidney disease (CKD). However, it was not traditionally recommended because of the possibility of impairing renal function and increasing proteinuria. Therefore, this review aricle has been conducted.

Does low-intensity physical exercise offer benefits to patients with chronic kidney disease?

Study design:
This review article included 21 RCTs with a intervention of at least 12 weeks and 927 patients.

The frequency of low-intensity physical exercise in 14 studies was 3 times per week during 30 minutes.

Results and conclusions:
The investigators found no differences in glomerular filtration rate or proteinuria between the intervention group (group with low-intensity physical exercise) and the control group (group without low-intensity physical exercise) [SMD = -0.3, p = 0.81 and SMD = 26.6, p = 0.82].

The investigators found positive effects on peak oxygen consumption [SMD = 2.5, p 0.001], functional capacity [SMD = 56.6, p 0.001], upper limb strength [SMD = 6.8, p 0.001] and haemoglobin [SMD = 0.3, p = 0.003] for the intervention group.

The investigators found an improvement on the quality of life, using the KDQOL-36 survey [SMD = 3.56, p = 0.02] and the SF-36 survey [SMD = 6.66, p = 0.02] for the intervention group.

The investigators concluded low-intensity physical exercise routinely has no negative impact on renal function. On the contrary, it improves aerobic and functional capacity, impacting positively on the quality of life.

Original title:
Impact of physical exercise in patients with chronic kidney disease: Sistematic review and meta-analysis by Villanego F, Naranjo J, […], Mazuecos A.

Link:
https://reader.elsevier.com/reader/sd/pii/S0211699520300266?token=62CEB2BCF50CE23B396565B5DC989F795AEEB75C666C74AA410FD2172DB39F90DBBB5D72BF3B4347C0C8AD2FEF8B0110

Additional information of El Mondo:
Find here more information/studies about kidney disease and sport nutrition.

Low-intensity physical exercises are a casual walk, a stretch session, a beginners' yoga class or tai chi.

Objectives:
Is there a causal relationship between dietary anthocyanins and reduced levels of systemic and vascular inflammation?

Study design:
This review article included 32 RCTs.

Results and conclusions:
The investigators found that dietary anthocyanins significantly decreased levels of C-reactive protein (CRP) [-0.33 mg/L, 95% CI = -0.55 to -0.11, p = 0.00], interleukin-6 (IL-6) [-0.41 ρg/mL, 95% CI = -0.70 to -0.13, p = 0.004], tumor necrosis factor-alpha (TNF-α) [-0.64 ρg/mL, 95% CI = -1.18 to -0.09, p = 0.023], intercellular adhesion molecule-1 [-52.4 ng/mL, 95% CI = -85.7 to -19.1, p = 0.002] and vascular adhesion molecule-1 (VCAM-1)  [-49.6 ng/mL, 95% CI = -72.7 to -26.5, p  0.001]. 

The investigators found that dietary anthocyanins significantly increased adiponectin level [0.75 μg/mL, 95% CI = 0.23 to 1.26, p = 0.004].

The investigators found subgroup analyses showed that administration of higher doses of anthocyanins (>300 mg/day) significantly decreased levels of CRP, IL-6, TNF-α and VCAM-1.

The investigators concluded that >300 mg/day dietary anthocyanins reduce the levels of systemic and vascular inflammation in the subjects.

Original title:
Impact of dietary anthocyanins on systemic and vascular inflammation: Systematic review and meta-analysis on randomised clinical trials by Fallah AA, Sarmast E, […], Jafari T.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31669599

Additional information of El Mondo:
Find here more information/studies about inflammation and anthocyanins.

Inflammation in the body can be measured by the following biomarker; the pro-inflammatory cytokines. The pro-inflammatory cytokines are the C-reactive protein (CRP), IL-1, interleukin-6 (IL-6), IL-8, MCP-1, the vascular adhesion molecule-1 (VCAM-1) and tumor necrosis factor alpha (TNF-α).

Objectives:
Is there a causal relationship between intake of pomegranate and decreased risk of getting inflammation in adults?

Study design:
This review article included 16 randomized controlled trials (RCTs) involving 572 subjects.

Results and conclusions:
The investigators found when compared to placebo, that pomegranate supplementation significantly reduced hs-CRP levels [WMD = -6.57 mg/L, 95% CI = -10.04 to -3.10, p = 0.000].

The investigators found when compared to placebo, that pomegranate supplementation significantly reduced IL-6 levels [WMD = -1.68 pg/mL, 95% CI = -3.52 to -0.157, p = 0.000].

The investigators found when compared to placebo, that pomegranate supplementation significantly reduced TNF-α levels [WMD = -2.37 pg/mL, 95% CI = -3.67 to -1.07, p = 0.00].

The investigators found no association between pomegranate supplementation and CRP levels [WMD = 2.19 mg/dL, 95% CI = -3.28 to 7.67, p = 0.61], E-selectin levels [WMD = 8.42 ng/mL, 95% CI = -22.9 to 39.8, p = 0.599], ICAM levels [WMD = -17.38 ng/mL, 95% CI = -53.43 to 18.66, p = 0.107], VCAM levels [WMD = -69.32 ng/mL, 95% CI = -229.26 to 90.61, p = 0.396] or MDA levels [WMD = 0.031 μmol/L, 95% CI = -1.56 to 0.218, p = 0.746].

The investigators concluded pomegranate supplementation reduces hs-CRP levels, IL-6 levels and TNF-α levels in adults.

Original title:
The effects of pomegranate supplementation on biomarkers of inflammation and endothelial dysfunction: A meta-analysis and systematic review by Wang P, Zhang Q, [...], Yao G.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32147056

Additional information of El Mondo:
Find here more information/studies about fruit and chronic diseases.

Inflammation in humans can be measured by biomarkers, such as highly sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6) and the tumor necrosis factor alpha (TNF-α).

Inflammation in humans can lower the resistance. A low resistance makes the body susceptible to diseases.
 

Objectives:
The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified. Therefore, this review article has been conducted.

Does hepatitis B virus infection increase risk of chronic kidney disease?

Study design:
This review article included 33 studies with a total of 7,849,849 patients.

Results and conclusions:
The investigators found in 11 cohort studies with 1,056,645 patients, that a positive HBV serologic status (hepatitis B virus infection) significantly increased risk of incidence of chronic kidney disease with 40% [adjusted HR = 1.40, 95% CI = 1.16 to 1.69, p 0.001, I2 = 49.5%, p 0.0001].

The investigators found in 10 cross-sectional studies with 3,222,545 patients, no relationship between hepatitis B virus infection and prevalence of chronic kidney disease [adjusted OR = 1.04, 95% CI = 0.90 to 1.218, p = 0.5].

The investigators found meta-regression analysis reported a relationship between positive HBsAg status and incidence of chronic kidney disease in the general population [p 0.015].

The investigators concluded hepatitis B virus infection increases risk of developing of chronic kidney disease in the adult general population. Studies aimed to understand the mechanisms responsible of such association are underway.

Original title:
HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis by Fabrizi F, Cerutti R, […], Messa P.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32037008

Additional information of El Mondo:
Find here more information/studies about kidney disease.
 

Objectives:
Lead is a known risk factor for amyotrophic lateral sclerosis (ALS). However, the results of studies exploring the relationship between lead exposure and the occurrence of ALS are inconsistent. Therefore, this review article has been conducted.

Does a high lead exposure increase risk of ALS?

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

Results and conclusions:
The investigators found a high lead exposure significantly increased risk of ALS with 28% [OR = 1.28, 95% CI = 1.02 to 1.63].
Subgroup and sensitivity analyses showed stable results.

The investigators concluded a high lead exposure increases risk of ALS.

Original title:
Population-based study of environmental/occupational lead exposure and amyotrophic lateral sclerosis: a systematic review and meta-analysis by Meng E, Mao Y, […], Jin W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31578652

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

Objectives:
Many studies have been reported that dietary meat intake may be associated with the risk of asthma in children, but the results are inconsistent. Therefore, this review article has been conducted.

Does dietary meat intake increase asthma in children?

Study design:
This review article included a total of 9 articles.

No publication bias was detected.

Results and conclusions:
The investigators found dietary meat intake 3 or more times per week compared with never/occasionally intake had no significant association with asthma risk among children [OR = 1.27, 95% CI  =  0.80-2.01, p =  0.308].
Not significant because OR of 1 was found in the 95% CI of 0.80 to 2.01. OR of 1 means no risk/association.

The investigators found, similarly, daily dietary intake of meat did not affect the risk of asthma in children when compared with never/occasionally intake [OR  =  1.13, 95% CI  =  0.93-1.37, p  =  0.234].

The investigators concluded dietary meat intake is not a risk factor for asthma in children. Due to some limitations that exist in this review article, more studies are needed to further assess the association between dietary meat intake and asthma risk in children.

Original title:
Dietary meat intake and risk of asthma in children: evidence from a meta-analysis by Zhang D, Cao L, [...], Wang Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31895767

Additional information of El Mondo:
Find here more information/studies about meat consumption and chronic diseases.
 

Objectives:
Is there an association between dietary factors and the risk of gout and hyperuricemia?
 
Study design:
This review article included 10 prospective cohort studies (the follow-up duration ranged from 6 years to 26 year) and 9 cross-sectional studies.

Based on the Newcastle-Ottawa Scale (NOS), the quality assessment of included studies yielded a mean NOS score of 7.1, suggesting the presence of high methodologic quality.

Results and conclusions:
The investigators found in meta-analysis that the risk of getting gout significantly increased with:
29% [OR = 1.29, 95% CI = 1.16-1.44] for dietary red meat intake;
31% [OR = 1.31, 95% CI = 1.01-1.68] for dietary seafoods intake;
158% [OR = 2.58, 95% CI = 1.81-3.66] for dietary alcohol intake;
114% [OR = 2.14, 95% CI = 1.65-2.78] for dietary fructose intake.

The investigators found in meta-analysis that the risk of getting gout significantly decreased with:
44% [OR = 0.56, 95% CI = 0.44-0.70] for dietary dairy products intake;
15% [OR = 0.85, 95% CI = 0.76-0.96] for dietary soy foods intake;
14% [OR = 0.86, 95% CI = 0.75-0.98] for dietary high-purine vegetables intake;
53% [OR = 0.47, 95% CI = 0.37-0.59] for dietary coffee intake.

The investigators found in meta-analysis that the risk of getting hyperuricemia (an excess of uric acid in the blood) significantly increased with:
24% [OR = 1.24, 95% CI = 1.04-1.48] for dietary red meat intake;
47% [OR = 1.47, 95% CI = 1.16-1.86] for dietary seafoods intake;
106% [OR = 2.06, 95% CI = 1.60-2.67] for dietary alcohol intake;
85% [OR = 1.85, 95% CI = 1.66-2.07] for dietary fructose intake.

The investigators found in meta-analysis that the risk of getting hyperuricemia (an excess of uric acid in the blood) significantly decreased with:
50% [OR = 0.50, 95% CI = 0.37-0.66] for dietary dairy products intake;
30% [OR = 0.70, 95% CI = 0.56-0.88] for dietary soy foods intake.

The investigators found in meta-analysis that the risk of getting hyperuricemia (an excess of uric acid in the blood) non-significantly increase with:
10% [OR = 1.10, 95% CI = 0.88-1.39] for dietary high-purine vegetables intake.

The investigators found in meta-analysis that the risk of getting hyperuricemia (an excess of uric acid in the blood) non-significantly decreased with 24% [OR = 0.76, 95% CI = 0.55-1.06] for dietary coffee intake in men.
Non-significantly because OR of 1 was found in the 95% CI of 0.55 to 1.06. OR of 1 means no risk/association.

The investigators found in meta-analysis that the risk of getting hyperuricemia (an excess of uric acid in the blood) significantly increased with 58% [OR = 1.58, 95% CI = 1.16-2.16] for dietary coffee intake in women.
Significant because OR of 1 was not found in the 95% CI of 1.16 to 2.16. OR of 1 means no risk/association.

The investigators concluded that the risk of hyperuricemia and gout is positively correlated with the dietary intake of red meat, seafoods, alcohol or fructose and negatively with dairy products or soy foods. High-purine vegetables show no association with hyperuricemia, but negative association with gout. Coffee intake is negatively associated with gout risk, whereas it is positively associated with hyperuricemia risk in women.

Original title:
Dietary factors and risk of gout and hyperuricemia: a meta-analysis and systematic review by Li R, Yu K and Li C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30485934

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

Objectives:
Postherpetic neuralgia (PHN) is the most distressful complication of herpes zoster. Postherpetic neuralgia results in an impaired quality of life and higher healthcare utilization. Vitamin B12 has been proven to be effective in pain relief for various conditions. Therefore, this review article has been conducted.

Do postherpetic neuralgia patients benefit from vitamin B12 supplementation?

Study design:
This review article included 4 RCTs (published between 2013 and 2016) including 383 participants.

Results and conclusions:
The investigators found compared with the placebo group, the vitamin B12 group exhibited a significant decrease in the Numeric Rating Scale score, with a mean difference of -4.01 [95% CI = -4.70 to -3.33].

The investigators found compared with the placebo group, vitamin B12 administration improved the quality of life of postherpetic neuralgia patients with moderate quality evidence and significantly decreased the number of patients using analgesics.

The investigators concluded that vitamin B12 appears to be an attractive complementary therapy for postherpetic neuralgia patients. However, further investigation is needed before conclusive recommendations can be made.

Original title:
Vitamin B12 for herpetic neuralgia: A meta-analysis of randomised controlled trials by Wang JY, Wu YH, [...], Lu PH.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30477853

Additional information of El Mondo:
Find more information/studies on vitamin B12 and chronic diseases right here.

Postherpetic neuralgia (PHN) is a nerve pain (neuralgia) that persists after a shingles rash has cleared. Postherpetic neuralgia is caused by the chickenpox (varicella-zoster) virus.
 

Objectives:
Does magnesium supplementation reduce C-reactive protein concentrations in humans?

Study design:
This review article included 8 RCTs (2004-2014) with 349 participants.

The mean age of participants ranged from 18 to 85 years.
The range of duration of the supplementation intervention across studies was from 8 h to 6.5 months.
The consumed range of magnesium dose in these studies was from 320 to 1500 mg/day. The baseline level (at the start of the study) of the CRP varied between the studies from 0.42 mg/dL as minimum to 9.4 mg/dL as maximum.

Results and conclusions:
The investigators found magnesium supplementation significantly reduced serum CRP levels [WMD = -1.33 mg/dL, 95% CI = -2.63 to -0.02, p 0.001, I2 = 29.1%, p 0.123] across all studies.
In leave-one-out sensitivity analyses, the pooled effect estimates remained similar across all studies for CRP levels [WMD = -1.33 mg/dL, 95% CI = -2.63 to -0.02].

The investigators found after adjustment of the effect size for potential publication bias using the “trim and fill” correction, no potentially missing studies were imputed in the funnel plot [WMD = -1.33 mg/dL, 95% CI = -2.63 to -0.02]. The “fail-safe N” test showed that 146 studies would be needed to bring the WMD down to a non-significant [p > 0.05] value.

The investigators found in random-effects meta-regression changes in serum CRP levels were independent of the dosage of magnesium [slope = -0.004, 95% CI = -0.03 to 0.02, p = 0.720, and duration [slope = -0.06, 95% CI = -0.37 to 0.24, p = 0.681] of supplementation.

The investigators found in 4 RCTs that subjects with a baseline CRP of ≥ 2 mg/dL had more significant reduction in the serum CRP level [WMD = -2.95 mg/dL, 95% CI = -3.35 to -2.25, p 0.001, I2 = 1.1%, p = 0.952] compared with subjects with a baseline CRP of 2 mg/dL [WMD = -0.23 mg/dL, 95% CI = -0.195 to -0.326, p 0.001, I2 = 1.3% p = 0.923].

The investigators found magnesium supplementation non-significantly reduced IL-6 levels [WMD = -0.16 pg/dL, 95% CI = -3.52 to 3.26, p = 0.236, I2 = 2.3%, p = 0.802] across all studies.

The investigators found magnesium supplementation significantly increased TNF-α levels [WMD = 1.97 pg/dL, 95% CI = 1.12 to 2.82, p = 0.043, I2 = 2.1%, p = 0.869] across all studies.

The investigators found magnesium supplementation non-significantly decreased fasting blood glucose (FBG) levels [WMD = -0.61 mg/dL, 95% CI = -2.72 to 1.48, p = 0.182, I2 = 6.1%, p = 0.742] across all studies.

The investigators found magnesium supplementation non-significantly decreased systolic blood pressure levels [WMD = -0.93 mmHg, 95% CI = -3.03 to 1.20, p = 0.293, I2 = 3.6%, p = 0.526] across all studies.

The investigators found magnesium supplementation non-significantly decreased diastolic blood pressure levels [WMD = -0.30 mmHg, 95% CI = -2.80 to 2.19, p = 0.639, I2 = 3.8%, p = 0.489] across all studies.

The investigators found magnesium supplementation non-significantly increased BMI levels [WMD = 0.27 kg/m², 95% CI = -0.59 to 1.15, p = 0.542, I2 = 2.0%, p = 0.906] across all studies.  

The investigators concluded that 320 to 1500 mg/day magnesium supplementation decreases serum CRP levels, especially with the baseline values ≥ 2 mg/dL. To provide more conclusive results and clarify the mechanistic pathways, RCTs with a larger sample size and a long-term follow-up period are warranted.

Original title:
Effect of magnesium supplements on serum C-reactive protein: a systematic review and meta-analysis by Mazidi M, Rezaie P and Banach M.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6040119/

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

Objectives:
Dietary salt reduction in the general population lowers blood pressure and cardiovascular risk. Despite being widely recommended, there is limited evidence as to whether this is applicable to individuals with end-stage renal disease (ESRD) receiving dialysis. Therefore, this review article has been conducted.

Study design:
This review article included 4 RCTs (91 participants), of which 3 were crossover trials and 1 was a parallel study.
Participants were 18 years and over; a reduction in salt intake of at least 1 g/day over 1 week and no concomitant interventions during the study.
The primary outcome was change in systolic and diastolic blood pressure.

Results and conclusions:
The investigators found dietary salt reduction was associated with an 8.4 mmHg [95% CI = 4.8-12.0, Ι2 = 0%] reduction in systolic blood pressure and a 4.4 mmHg [95% CI = 2.2-6.6, Ι2 = 0%] reduction in diastolic blood pressure.

The investigators concluded that a reduction in salt intake of at least 1 g/day over 1 week reduces blood pressure among individuals with end-stage renal disease (ESRD) receiving dialysis.

Original title:
The effect of dietary salt on blood pressure in individuals receiving chronic dialysis: a systematic review and meta-analysis of randomised controlled trials by Cole NI, Swift PA, […], Suckling RJ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30413764

Additional information of El Mondo:
Find more information/studies on lowering blood pressure, salt intake and chronic disease right here.
 

Objectives:
The association between coffee consumption and the circulating level of adiponectin and leptin has been evaluated in several epidemiological studies with conflicting results. Therefore, this review article has been conducted.

Is there an association between coffee consumption and the circulating level of adiponectin and leptin in humans?

Study design:
This review article included 12 cross-sectional studies.

Results and conclusions:
The investigators found when compared the highest versus the lowest coffee intake category, coffee consumption was associated with a higher circulating adiponectin level [SMD = 0.11, 95% CI = 0.06 to 0.17, p 0.001].

The investigators found in subgroup analysis when compared the highest versus the lowest coffee intake category, coffee consumption was associated with a higher circulating adiponectin level in women [SMD = 0.11, 95% CI = 0.02 to 0.20, p = 0.01], but not in men [SMD = 0.03, 95% CI = -0.08 to 0.14, p = 0.59].

The investigators found when compared the highest versus the lowest coffee intake category, coffee consumption was associated with a lower circulating leptin level [SMD = -0.19, 95% CI = -0.28 to -0.10, p 0.001].

The investigators concluded that coffee consumption is associated with a higher circulating level of adiponectin in women and a lower circulating level of leptin. However, more well-designed prospective cohort studies and randomised controlled trials are needed to further elaborate the concerned issues.

Original title:
Associations of coffee consumption with circulating level of adiponectin and leptin. A meta-analysis of observational studies by Zhang Y and Zhang DZ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29513118

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

Adiponectin is a unique adipokine, which is specifically and abundantly expressed in adipose tissues and improves insulin resistance. Having insulin resistance may increase the risk of type 2 diabetes and metabolic syndrome.

Objectives:
Inflammation is associated with an increased risk of a range of chronic diseases. A diet high in fruit and vegetables may help to reduce inflammation, as fruit and vegetables are rich sources of antioxidants and other biologically active substances, which may improve immune function. Therefore, this meta-analysis (systematic review) has been conducted.

Does fruit or vegetables intake reduce inflammation and improve immune function?

Study design:
This review article included 71 clinical trials and 12 were observational studies (n = 10 cross-sectional studies and n = 2 cohort studies).

Results and conclusions:
The investigators found among observational studies (n = 10 studies) an inverse association between intakes of fruit or vegetables and inflammatory biomarkers.

The investigators found the majority of the intervention studies (n = 48 studies) reported beneficial effects of fruit or vegetable intake on ≥1 biomarker of systemic or airway inflammation.

The investigators found a meta-analysis of included studies showed that fruit or vegetable intake significantly decreased circulating levels of C-reactive protein and tumor necrosis factor-α [p 0.05] and significantly increased the γδ-T cell population [p 0.05].

The investigators concluded that higher intakes of fruit and vegetables lead to both a reduction in proinflammatory mediators and an enhanced immune cell profile.

Original title:
Effects of fruit and vegetable consumption on inflammatory biomarkers and immune cell populations: a systematic literature review and meta-analysis by Hosseini B, Berthon BS, […], Wood LG.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29931038

Additional information of El Mondo:
Find more information/studies on fruit and vegetables and chronic disease right here.

The level of C-reactive protein (CRP), which can be measured in your blood, increases when there's inflammation in your body.

Tumour necrosis factor-alpha (TNF-alpha) is recognized as an important mediator in many cytokine-dependent inflammatory events.

 

Objectives:
Although glucosamine and chondroitin sulfate have showed beneficial effects on joint tissues in osteoarthritis (OA), their therapeutic use in the clinical setting is still debatable. Therefore, this meta-analysis (systematic review) has been conducted.

Do glucosamine and chondroitin sulfate supplements relieve pain of knee osteoarthritis?

Study design:
This review article included RCTs.

The pain of knee osteoarthritis was measured using the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) and/or the Visual Analog Scale (VAS).

Results and conclusions:
The investigators found that glucosamine supplements significantly reduced pain of knee osteoarthritis (expressed as Visual Analog Scale (VAS) [WMD = - 7.41 mm, 95% CI = - 14.31 to - 0.51, p = 0.04].
Significant means that there is an association with a 95% confidence.

The investigators found that chondroitin supplements significantly reduced pain of knee osteoarthritis (expressed as Visual Analog Scale (VAS) [WMD = - 8.35 mm, 95% CI = - 11.84 to - 4.85, p  0.00001].
Significant because the found p-value of 0.00001 is less than 0.05.

The investigators found that the combination of glucosamine and chondroitin supplements non-significantly reduced pain of knee osteoarthritis (expressed as Visual Analog Scale (VAS) [WMD = - 0.28 mm, 95% CI = - 8.87 to 8.32, p = 0.95].
Non-significantly because the found p-value of 0.95 is greater than 0.05.

The investigators found that none of the glucosamine, chondroitin supplements or their combination had a significant positive effect on the total WOMAC index and its subscores.

The investigators concluded that oral supplementation with glucosamine or chondroitin sulfate reduces pain in knee osteoarthritis. However, there is no additional effect using both therapeutic agents in combination for the management of symptomatic knee osteoarthritis.

Original title:
Effect of glucosamine and chondroitin sulfate in symptomatic knee osteoarthritis: a systematic review and meta-analysis of randomized placebo-controlled trials by Simental-Mendía M, Sánchez-García A, […], Simental-Mendía LE.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29947998

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

 

Objectives:
In the past, some observational studies have been carried out on the relationship between milk and dairy intake and risk of acne occurrence. However, their results were conflicting. Therefore, this meta-analysis (systematic review) has been conducted.

Does milk and dairy intake increase risk of acne?

Study design:
This review article included observational studies.

Results and conclusions:
The investigators found for highest compared with lowest category of dairy intake a significantly increased risk of 161% for acne [OR = 2.61, 95% CI = 1.20 to 5.67].

Significant means that there is an association with a 95% confidence.

The investigators found for highest compared with lowest category of total milk intake a significantly increased risk of 48% for acne [OR = 1.48, 95% CI = 1.31 to 1.66].
Significantly means it can be said with a 95% confidence that a high total milk intake really increased the risk of getting acne with 48%. 

The investigators found for highest compared with lowest category of low-fat milk intake a significantly increased risk of 25% for acne [OR = 1.25, 95% CI = 1.10 to 1.43].
Significant because OR of 1 was not found in the 95% CI of 1.10 to 1.43. RR of 1 means no risk/association.

The investigators found for highest compared with lowest category of skim milk intake a significantly increased risk of 82% for acne [OR = 1.82, 95% CI = 1.34 to 2.47].

The investigators found results of dose-response analysis revealed a significant linear relationship between dairy, whole milk and skim milk and risk of acne and a nonlinear association between dairy, milk, low-fat milk and skim milk intake and acne.

The investigators concluded there is a positive relationship between dairy, total milk, whole milk, low-fat and skim milk consumption and acne occurrence. In contrary, there is no significant association between yogurt/cheese and acne development.

Original title:
Dairy intake and acne development: A meta-analysis of observational studies by Aghasi M, Golzarand M, […], Taheri F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29778512

Additional information of El Mondo:
Find more information/studies on dairy products and chronic disease right here.
 

Objectives:
The evidence is mixed on the use of long chain omega 3 fatty acids in the prevention and management of childhood asthma. Therefore, this meta-analysis (systematic review) has been conducted.

Does fish consumption reduce risk of childhood asthma?

Study design:
This review article included 23 observational studies on fish intake in association with childhood asthma.

Results and conclusions:
The investigators found in 15/23 studies early introduction of fish (6-9 months) and regular consumption (at least once a week) improved asthma symptoms and reduced risk in children 0-14 years as compared to no fish consumption; 6/23 showed no effect and 2/23 studies suggested adverse effects.

The investigators found a significantly reduced risk of 25% [OR = 0.75, 95% CI = 0.60-0.95] for all fish intake on current asthma in children up to 4.5 years old. 

The investigators found a significantly reduced risk of 38% [OR = 0.62, 95% CI = 0.48-0.80] for all fish intake on current wheeze in children up to 4.5 years old.

The investigators found as compared to no fish intake, a significantly reduced risk of 65% [OR = 0.35, 95% CI = 0.18-0.67] for fatty fish intake on asthma in children 8-14 years old. 

The investigators concluded that introduction of fish early in life (6-9 months) and regular consumption of all fish (at least once a week) reduces asthma and wheeze in children up to 4.5 years old, while fatty fish intake has beneficial effects in older children (8-14 years). Future well-designed clinical trials are recommended to confirm the promising findings documented in this literature analysis.

Original title:
The role of fish intake on asthma in children: A meta-analysis of observational studies by Papamichael MM, Shrestha SK, [...], Erbas B.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29524247

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

Objectives:
Zinc is an essential trace element for living organisms and their biological processes. Zinc plays a key role in more than 300 enzymes and it is involved in cell communication, proliferation, differentiation and survival. Zinc also plays a role in regulating the immune system with implications in pathologies where zinc deficiency and inflammation are observed. Therefore, this meta-analysis (systematic review) has been conducted.

Do zinc deficiency increase risk of autoimmune disorders?

Study design:
This review article included 62 case-control studies.

The manner of collecting and investigating zinc samples was very heterogeneous.

Results and conclusions:
The investigators found in fixed model that serum zinc concentration of autoimmune disease patients was significantly lower than in controls [mean effect = -1.19, 95% CI = -1.26 to -1.11].

The investigators found in fixed model that plasma zinc concentration of autoimmune disease patients was significantly lower than in controls [mean effect = -3.97, 95% CI = -4.08 to -3.87].

The investigators concluded that a deficiency of zinc in serum and plasma increases risk of autoimmune disorders in humans.

Original title:
Zinc Status and Autoimmunity: A Systematic Review and Meta-Analysis by Sanna A, Firinu D, […], Valera P.

Link:
http://www.mdpi.com/2072-6643/10/1/68/htm

Additional information of El Mondo:
Find here more information/studies about zinc and chronic diseases.

An autoimmune disease is a condition in which your immune system mistakenly attacks your body. These are the most common autoimmune diseases:  

1. Addison’s disease: Caused by an adrenal hormone insufficiency. Addison’s disease can lead to muscle weakness and fatigue, nausea, weight loss, irritability, low blood pressure, low blood sugar and depression.
2. Celiac disease (gluten allergy): Celiac disease is a reaction to gluten (found in barley, rye and wheat) that causes damage to the lining of the small intestine.
3. Graves’ disease: Caused by extremely overactive thyroid gland. People who have Graves’ disease may have difficulty sleeping, bulging of the eyes, irritability, brittle hair, unexplained weight loss, sensitivity to heat, muscle weakness, light menstrual periods and shakiness of the hands. On the other hand, some people with Graves’ disease may experience no symptoms at all.
4. Hashimoto’s disease: Caused by inflammation of the thyroid gland. Although sometimes no symptoms occur, Hashimoto’s thyroiditis often results in a goiter (enlargement of the thyroid gland, which may be visible as a bulge in the neck), weight gain, fatigue, muscle weakness, depression, cold sensitivity, dry hair and skin, and constipation.
5. Inflammatory bowel disease: This disease refers to a group of inflammatory diseases of the colon and small intestine.
6. Multiple Sclerosis or MS: This disease affects the brain and spinal cord. People who have MS may experience weakness, trouble with balance and coordination, problems speaking and walking, tremors, paralysis and numbness in the extremities.
7. Psoriasis: This is a skin condition that causes redness and irritation as well as thick, flaky, silver-white patches.
8. Pernicious anemia: Caused by the inability to absorb vitamin B12 leading to a decrease in red blood cells.
9. Reactive arthritis: Caused by inflammation of joints, the urethra and eyes.
10. Raynaud’s phenomenon: People with Raynaud’s have a problem with blood flow, resulting in numbness, tingling of the fingers, discoloration, toes and tip of the nose with exposure to cold temperatures.
11. Rheumatoid arthritis: In rheumatoid arthritis, autoimmunity causes the immune system to attack tissues in the joints. It typically affects the small joints in your hands and feet causing painful swelling, stiffness and loss of movement in the joints that can eventually result in bone erosion and joint deformity.
12. Scleroderma: Scleroderma is a connective tissue disease that causes changes in skin, muscles, blood vessels and internal organs.
13. Sjögren’s syndrome: Caused by destruction of the glands that produce tears and saliva causing dry eyes and mouth.
14. Systemic lupus erythematosus: In lupus, antibodies made by the immune system attack the body. Systemic lupus erythematosus can affect skin, kidneys, joints and brain.
15. Type 1 diabetes: In type 1 diabetes, the immune system attacks cells in the pancreas that produce insulin. When your insulin levels are insufficient, your body cannot control your blood glucose level, which can lead to a number of problems, including kidney failure, stroke, vision loss, circulation problems and heart disease.