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/

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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:
Do omega-3 fatty acid supplements (EPA and DHA) improve sarcopenia-related performances among the elderly?

Study design:
This review article included 10 RCTs with 552 participants.
The number of study participants ranged from 24 to 126 and the durations of the interventions spanned 10 to 24 weeks.
The doses ranged from 0.16 to 2.6 g/day of EPA and from 0 to 1.8 g/day of DHA.
The mean ages of the participants across the RCTs ranged from 63 to 75 years old.

Results and conclusions:
The investigators found in subgroup analyses that omega-3 fatty acid supplements (EPA and DHA) at more than 2 g/day significantly increased muscle mass among the elderly [SMD = 0.67 kg, 95% CI = 0.16 to 1.18, p 0.05].

The investigators found in subgroup analyses that omega-3 fatty acid supplements (EPA and DHA) during more than 6 months significantly improved walking speed among the elderly [SMD = 1.78 m/sec, 95% CI = 1.38 to 2.17, p 0.05].

The investigators concluded that taking at least 2 grams of omega-3 supplements (EPA and DHA) per day increases muscle mass among the elderly, while taking omega-3 supplements for at least 6 months increases walking speed among the elderly.

Original title:
Effects of Omega-3 Fatty Acids on Muscle Mass, Muscle Strength and Muscle Performance among the Elderly: A Meta-Analysis by Huang YH, Chiu WC, […], Wang YH.

Link:
https://www.mdpi.com/2072-6643/12/12/3739/htm

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EPA and DHA are present in fish.
 

Objectives:
Does calcium combined with vitamin D supplementation reduce risk of osteoporosis in postmenopausal women?

Study design:
This review article included 10 RCTs.

Results and conclusions:
The investigators found calcium combined with vitamin D supplementation significantly increased total bone mineral density [SMD = 0.537, 95% CI = 0.227 to 0.847] in postmenopausal women.

The investigators found calcium combined with vitamin D supplementation significantly increased lumbar spine bone mineral density [SMD = 0.233, 95% CI = 0.073 to 0.392, p 0.001] in postmenopausal women.

The investigators found calcium combined with vitamin D supplementation significantly increased arms bone mineral density [SMD = 0.464, 95% CI = 0.186 to 0.741] in postmenopausal women.

The investigators found calcium combined with vitamin D supplementation significantly increased femoral neck bone mineral density [SMD = 0.187, 95% CI = 0.010 to 0.364] in postmenopausal women.

The investigators found calcium combined with vitamin D supplementation significantly reduced risk of hip fracture with 13.6% [RR = 0.864, 95% CI = 0.763 to 0.979] in postmenopausal women.

The investigators found in subgroup analysis that calcium combined with 400 IU/d (10 mcg/d) vitamin D supplementation significantly increased femoral neck bone mineral density [SMD = 0.335, 95% CI = 0.113 to 0.558] in postmenopausal women.

The investigators found in subgroup analysis that dairy products fortified with calcium and vitamin D significantly increased total bone mineral density [SMD = 0.784, 95% CI = 0.322 to 1.247] in postmenopausal women.

The investigators found in subgroup analysis that dairy products fortified with calcium and vitamin D significantly increased lumbar spine bone mineral density [SMD = 0.320, 95% CI = 0.146 to 0.494] in postmenopausal women.

The investigators concluded that dairy products fortified with calcium and vitamin D have a favourable effect on bone mineral density. Furthermore, calcium combined with vitamin D supplementation could prevent osteoporosis hip fracture in postmenopausal women.

Original title:
Effects of combined calcium and vitamin D supplementation on osteoporosis in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials by Liu C, Kuang X […], Li D.

Link:
https://pubmed.ncbi.nlm.nih.gov/33237064/

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Find more information/studies on dairy products consumption, calcium and vitamin D right here.

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/

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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/

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Find here more information/studies about fish consumption.

Objectives:
Isoflavones have a structure similar to 17β-estradiol, so they may be useful to postmenopausal women in preventing bone loss related to estrogen deficiency. Therefore, this review article has been conducted.

Do isoflavone supplements increase bone mineral density (BMD) in postmenopausal women?

Study design:
This review article included 63 RCTs, involving 6,427 postmenopausal women.

Isoflavone interventions were generally safe and well tolerated.

Results and conclusions:
The investigators found statistically significant differences in bone mineral density at the last follow-up visit between the two groups (isoflavones vs. control) at the lumbar spine [MD = 21.34 mg/cm², 95% CI = 8.21 to 34.47 mg/cm², p = 0.001], the femoral neck [MD = 28.88 mg/cm², 95% CI = 15.05 to 42.71 mg/cm², p 0.0001] and the distal radius [MD = 19.27 mg/cm², 95% CI = 5.65 to 32.89 mg/cm², p = 0.006].
This improved bone mineral density was found for genistein 54 mg/day and ipriflavone (a synthetic isoflavone) 600 mg/day.

The investigators concluded isoflavone interventions, genistein (54 mg/day) and ipriflavone (600 mg/day) in particular, have beneficial effects on bone mineral density outcomes and are safe in postmenopausal women. They may be considered as a complementary or alternative option in the prevention and treatment of menopause-related osteoporosis.

Original title:
Effects of Isoflavone Interventions on Bone Mineral Density in Postmenopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Sansai K, Takuathung MN, [...], Koonrungsesomboon N.

Link:
https://pubmed.ncbi.nlm.nih.gov/32524173/

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Find more information/studies on isoflavones and elderly right here.

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:
Has oral supplementation of vitamin B (vitamins B1, B6, B12 and folic acid alone or combined) preventive effect on cognitive decline in cognitively unimpaired individuals?

Study design:
This review article included 20 RCTs, ranging from 23 to 2,919 participants per study, with a total of 12,697 participants.
8 of these 20 RCTs were deemed appropriate for the meta-analysis.

Results and conclusions:
The investigators found meta-analysis did not yield a significant overall effect of supplementation with vitamin B on cognitive function [SMD = 0.02, 95% CI = -0.034 to 0.08]. A sensitivity analysis focusing on specific risk factors did not alter this result.
Some studies reported isolated significant effects of the intervention on secondary outcomes. However, these findings were outnumbered by the number of cognitive tests that did not yield significant effects.

The investigators concluded there is no overall evidence that oral vitamin B supplementation prevent cognitive decline in cognitively unimpaired individuals. The results of this review do not provide evidence that population groups with certain risk factors would profit more from the intervention than others.

Original title:
Vitamin B-Can It Prevent Cognitive Decline? A Systematic Review and Meta-Analysis by Behrens A, Graessel E, [...], Donath C.

Link:
https://systematicreviewsjournal.biomedcentral.com/articles/10.1186/s13643-020-01378-7

Additional information of El Mondo:
Find more information/studies on vitamins B1, B6, B12 and folic acid and dementia right here.

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/

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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

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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:
Previous studies did not draw a consistent conclusion about the effects of vitamin K combined with vitamin D on human skeletal quality. Therefore, this review article has been conducted.

Does vitamin K combined with vitamin D supplementation increase bone mineral density (BMD)?

Study design:
This review article included 8 RCTs with a total of 971 participants.

Results and conclusions:
The investigators found vitamin K combined with vitamin D supplementation significantly increased total bone mineral density (BMD) [pooled effect size = 0.316, 95% CI = 0.031 to 0.601].

The investigators found vitamin K combined with vitamin D supplementation significantly decreased levels of undercarboxylated osteocalcin [effect size = -0.945, 95% CI = -1.113 to -0.778].

The investigators found simultaneously, subgroup analysis showed that K2 or vitamin K (not specified) supplement less than 500 μg/d, when combined with vitamin D significantly increased total bone mineral density compared with the control group fed a normal diet or the group with no treatment [effect size = 0.479, 95% CI = 0.101 to 0.858 and effect size = 0.570, 95% CI = 0.196 to 0.945, respectively).

The investigators concluded the combination of vitamin K and D supplement increases the total bone mineral density (BMD) and decreases levels of undercarboxylated osteocalcin and a more favorable effect is expected when less than 500 μg/d vitamin K2 is used.

Original title:
The combination effect of vitamin K and vitamin D on human bone quality: a meta-analysis of randomized controlled trials by Kuang X, Liu C, […], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32219282

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Find more information/studies on elderly, vitamin D and K right here.

Undercarboxylated osteocalcin represents inadequately carboxylated osteocalcin and this fraction increases with vitamin K insufficiency.

Objectives:
Is there a causal relationship between dietary intake of dairy products and a positive effect on bone mineral density (BMD) in healthy postmenopausal women?

Study design:
This review article included 6 RCTs with a total of 618 participants. Milk was the main dairy product used in the trials.

Results and conclusions:
The investigators found there was a significant association between dairy product consumption and bone mineral density of the lumbar spine [SMD = 0.21, 95% CI = 0.05 to 0.37, p = 0.009], femoral neck [SMD = 0.36, 95% CI = 0.19 to 0.53, p  0.001], total hip [SMD = 0.37, 95% CI = 0.20 to 0.55, p  0.001] and total body [SMD = 0.58, 95% CI = 0.39 to 0.77, p  0.001].

The investigators found subgroup analysis showed a positive effect of dairy product consumption on the bone mineral density of the total hip starting from 12 months and the femoral neck starting from 18 months. There was also a positive association with the bone mineral density in the 4 sites in people living in low-calcium intake countries.

The investigators concluded that there is a causal relationship between dietary intake of dairy products, particularly milk during at least 12 months and a positive effect on bone mineral density (BMD) in healthy postmenopausal women. Therefore, dairy product consumption should be considered an effective public health measure to prevent osteoporosis in postmenopausal women.

Original title:
Effects of dairy products on bone mineral density in healthy postmenopausal women: a systematic review and meta-analysis of randomized controlled trials by Shi Y, Zhan Y, [...], Jiang Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32185512

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Find more information/studies on dairy products and elderly right here.

Menopause is the point when a woman no longer has menstrual periods for at least 12 months. Postmenopause is the stage after menopause.

Objectives:
Does a high LDL cholesterol level (bad cholesterol) increase risk of Alzheimer's disease (AD)?

Study design:
This review article included 26 case-control studies involving 7,033 participants (2,266 Alzheimer's disease patients and 4,767 non-dementia controls).

There was no significant evidence of publication bias according to the results of Egger's test [p = 0.084].

Results and conclusions:
The investigators found results from the meta-analysis of 26 studies revealed higher levels of LDL cholesterol (>121 mg/dL) in Alzheimer's disease than that of non-dementia controls [SMD = 0.35, 95% CI = 0.12 to 0.58, p 0.01], which was consistent with the results of the fixed-effect model [SMD = 0.16, 95% CI = 0.10 to 0.22, p 0.01].
Sensitivity analyses showed that no single study exerted substantial influence on the pooled effect size after sequentially omitting a study.

The investigators found subgroup analysis of age showed LDL cholesterol levels in Alzheimer's disease patients aged 60-70 were higher than that of non-dementia [60 ≤ age 70: SMD = 0.80, 95% CI = 0.23 to 1.37, p 0.01].  

The investigators concluded that elevated concentration of LDL cholesterol (>121 mg/dL) is a risk factor for Alzheimer's disease. This strong association is significant in patients with Alzheimer's disease aged 60-70 years, but vanishes with increasing age. This review article provides a promising strategy for reducing the risk of Alzheimer's disease in patients with hyperlipidemia, which may be achieved by regulating LDL cholesterol concentration between 103.9 and 121 mg/dL with statins. Prospective studies that exclude potential confounders, more scientific design and adequate long-term follow-up are needed to validate this hypothesis.

Original title:
Low-Density Lipoprotein Cholesterol and Alzheimer's Disease: A Systematic Review and Meta-Analysis by Zhou Z, Liang Y, […], Zhao M.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002548/

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Find more information/studies on cholesterol and Alzheimer's disease right here.
 

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:
Several epidemiological studies have been performed to evaluate the association of dietary intake of vitamin C-oriented foods (DIVCF) with risk of fracture and bone mineral density (BMD) loss, but the results remain controversial. Therefore, this review article has been conducted.

Does dietary intake of vitamin C-oriented foods decrease risk of fracture and bone mineral density loss?

Study design:
This review article included 4 cohort studies, 11 case-control studies and 2 cross-sectional studies with a total of 19,484 subjects.

The studies received a quality score of ≥5, indicating that the methodological quality of the studies was generally good.

No evidence of publication bias was found in the evaluation of dietary intake of vitamin C-oriented foods and the risk of hip fracture.

Results and conclusions:
The investigators found that the people with a higher dietary intake of vitamin C-oriented foods had a significantly 34% [RR = 0.66, 95% CI = 0.47 to 0.94, I2 = 79.5%, p = 0.000] lower risk of hip fracture.

The investigators found that the people with a higher dietary intake of vitamin C-oriented foods had a significantly 42% [RR = 0.58, 95% CI = 0.38 to 0.89] lower risk of hip fracture in case-control studies.
However, this reduced risk was not significant in cohort studies [RR = 0.92, 95% CI = 0.59 to 1.44]. 

The investigators found that the people with a higher dietary intake of vitamin C-oriented foods had a significantly 34% [RR = 0.66, 95% CI = 0.48 to 0.92] lower risk of osteoporosis.

The investigators found higher dietary intake of vitamin C-oriented foods was negatively associated with the risk of bone mineral density loss at the lumbar spine [pooled r = 0.15, 95% CI = 0.09 to 0.23] and at the femoral neck [pooled r = 0.20, 95% CI = 0.11 to 0.34].

The investigators concluded that higher dietary intake of vitamin C-oriented foods reduces the risk of hip fracture, osteoporosis and bone mineral density loss, suggesting that people should consume more vitamin C to decrease the risk of hip fracture, osteoporosis and bone mineral density loss, particularly lumbar spine and femoral neck.

Original title:
Can Dietary Intake of Vitamin C-Oriented Foods Reduce the Risk of Osteoporosis, Fracture, and BMD Loss? Systematic Review With Meta-Analyses of Recent Studies by Zeng LF, Luo MH, […], Liu J.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7008177/

Additional information of El Mondo:
Find more information/studies on vitamin C and elderly right here.
 

Objectives:
Current evidence on associations between intakes of linoleic acid (LA), the predominant n-6 (ω-6) fatty acid and mortality is inconsistent and has not been summarized by a systematic review and meta-analysis. Therefore, this review article has been conducted.

Does higher linoleic acid intake, assessed by dietary surveys or biomarkers decrease mortality from all causes, cardiovascular disease (CVD) and cancer?

Study design:
This review article included 44 prospective cohort studies with 811,069 participants with dietary intake assessment (170,076 all-cause, 50,786 cardiovascular disease and 59,684 cancer deaths) and 65,411 participants with biomarker measurements (9,758 all-cause, 6,492 cardiovascular disease and 1,719 cancer deaths).

Meta-regressions suggested baseline age and dietary assessment methods as potential sources of heterogeneity for the association between linoleic acid and total mortality.

Results and conclusions:
The investigators found when compared with the lowest categories of dietary linoleic acid intake, that the highest categories of dietary linoleic acid intake significantly reduced total mortality risk with 13% [pooled RR = 0.87, 95% CI = 0.81 to 0.94, I2 = 67.9%].

The investigators found when compared with the lowest categories of dietary linoleic acid intake, that the highest categories of dietary linoleic acid intake significantly reduced cardiovascular disease mortality risk with 13% [pooled RR = 0.87, 95% CI = 0.82 to 0.92, I2 = 3.7%].

The investigators found when compared with the lowest categories of dietary linoleic acid intake, that the highest categories of dietary linoleic acid intake significantly reduced cancer mortality risk with 11% [pooled RR = 0.89, 95% CI = 0.85 to 0.93, I2 = 0%].

The investigators found for each standard deviation increment in linoleic acid concentrations in adipose tissue/blood compartments a significantly reduced total mortality risk of 9% [pooled RR = 0.91, 95% CI = 0.87 to 0.95, I2 = 64.1%].

The investigators found for each standard deviation increment in linoleic acid concentrations in adipose tissue/blood compartments a significantly reduced cardiovascular disease mortality risk of 11% [pooled RR = 0.89, 95% CI = 0.85 to 0.94, I2 = 28.9%].

The investigators found for each standard deviation increment in linoleic acid concentrations in adipose tissue/blood compartments a significantly reduced cancer mortality risk of 9% [pooled RR = 0.91, 95% CI = 0.84 to 0.98, I2 = 26.3%].

The investigators concluded higher linoleic acid intake, assessed by dietary surveys or biomarkers, reduces risk of mortality from all causes, cardiovascular disease and cancer. These data support the potential long-term benefits of PUFA intake in lowering the risk of cardiovascular disease and premature death.

Original title:
Dietary intake and biomarkers of linoleic acid and mortality: systematic review and meta-analysis of prospective cohort studies by Li J, Guasch-Ferré M, […], Hu FB.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32020162

Additional information of El Mondo:
Find more information/studies on linoleic acid intake and mortality right here.
Linoleic acid is a PUFA.
 

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:
Alzheimer's disease (AD) is a common type of dementia, which has caused heavy global economic and health burden and the using of statins to treat Alzheimer disease has caused widely debated. Therefore, this review article has been conducted.

Does statin use decrease Alzheimer disease?

Study design:
This review article included a total of 9 RCTs containing 1,489 patients. Of them, 742 patients in the statins group, 747 patients in the control group (group without statins).

There were 9 studies used the MMSE scale, 5 studies used the ADAS-Cog scale, 4 studies used the NPI scale and 6 studies used the ADL scale.

Sensitivity analysis and publication bias test were both negative and the results were relatively reliable and stable.

Results and conclusions:
The investigators found meta-analysis of the 9 studies that reported the MMSE scale scores indicated that there was no significant effect of statins as compared with control group [pooled WMD = 1.09, 95% CI = -0.00 to 2.18, p = 0.05, I2 = 87.9%].

The investigators found meta-analysis of the 5 studies that reported the ADAS-Cog scale scores also indicated that there was no significant effect of statins as compared with control group [pooled WMD = -0.16, 95% CI = -2.67 to 2.36, p = 0.90, I2 = 80.1%].

The investigators found meta-analysis of the 4 studies that reported the NPI scale scores indicated that treatment with statins significantly slowed the rise in the NPI scale scores as compared with control group [pooled WMD = -1.16, 95% CI = -1.88 to -0.44, p = 0.002, I2 = 45.4%].

The investigators found meta-analysis of the 6 studies that reported the ADL scale scores indicated that treatment with statins significantly improve patients' daily living ability [pooled WMD = -4.06, 95% CI = -6.88 to -1.24, p = 0.005, I2 = 86.7%].

The investigators found results of subgroup analysis indicated that the use of statins in the short term (≤ 12 months) associated with the change of the MMSE scale scores [pooled WMD = 1.78, 95% CI = 0.53 to 3.04, p = 0.005, I2 = 79.6%].

The investigators concluded statins used in Alzheimer disease patients have beneficial effects on the scores of MMSE scale in the short term (≤ 12 months) and statins slow the deterioration of neuropsychiatric status and improve activities of daily living ability in Alzheimer disease patients.

Original title:
The efficacy of statins in the treatment of Alzheimer's disease: a meta-analysis of randomized controlled trial by Xuan K, Zhao T, […], Sun Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31930449

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

Objectives:
Despite growing evidence for the association between other dietary macronutrients and bone health, limited and inconsistent knowledge is available regarding carbohydrate intake. Therefore, this review article has been conducted.

Does a high carbohydrate intake increase risk of fracture?

Study design:
This review article included observational studies.

Results and conclusions:
The investigators found no association between carbohydrate intake and the risk of fracture in high versus low intake meta-analysis [overall relative risk = 1.24, 95% CI = 0.84 to 1.84, p = 0.27, I2 = 57.7%, p = 0.05].

The investigators found, moreover, there was no relationship between carbohydrate intake and the risk of fracture in both linear [overall RR = 1.00, 95% CI = 0.94 to 1.05, p = 0.88, I2 = 68.1%, p = 0.48] and nonlinear [p non-linearity = 0.14] models.

The investigators concluded high carbohydrate intake does not increase risk of fracture.

Original title:
Dietary carbohydrate intake and risk of bone fracture: a systematic review and meta-analysis of observational studies by Mozaffari H, Daneshzad E and Azadbakht L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31982636

Additional information of El Mondo:
Find more information/studies on carbohydrates and elderly right here.
 

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:
Which factors increase risk of dementia?

Study design:
This review article included 34 prospective cohort studies, among which 24 were eligible for meta-analysis. A total of 159,594 non-demented adults were enrolled at baseline before 65 years and 13,540 people were diagnosed with dementia after follow-up.

Results and conclusions:
The investigators found obesity significantly increased risk of dementia with 78% [RR = 1.78, 95% CI = 1.31-2.41].

The investigators found diabetes mellitus significantly increased risk of dementia with 69% [RR = 1.69, 95% CI = 1.38-2.07].

The investigators found current smoking significantly increased risk of dementia with 61% [RR = 1.61, 95% CI = 1.32-1.95].

The investigators found hypercholesterolemia significantly increased risk of dementia with 57% [RR = 1.57, 95% CI = 1.19-2.07].
However, the sensitivity analyses showed that the result of hypercholesterolemia was not reliable, which need to be confirmed by more high-quality studies.

The investigators found hypertension significantly increased risk of dementia with 41% [RR = 1.41, 95% CI = 1.23-1.62] for borderline blood pressure.

The investigators found hypertension significantly increased risk of dementia with 72% [RR = 1.72, 95% CI = 1.25-2.37] for high systolic blood pressure.
However, the sensitivity analyses showed that the result of high systolic blood pressure was not reliable, which need to be confirmed by more high-quality studies.

The investigators found hyperhomocysteinemia, psychological stress and heavy drinking were also associated with elevated dementia risk.

The investigators found, in addition, physical exercise, a healthy diet and hormone therapy in middle age were associated with the reduction of dementia risk.

The investigators concluded middle-aged people with obesity or diabetes and current smokers in midlife are at higher risk of developing dementia later in life.

Original title:
Midlife Modifiable Risk Factors for Dementia: A Systematic Review and Meta-analysis of 34 Prospective Cohort Studies by Li XY, Zhang M, [...], Tan L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31902364

Additional information of El Mondo:
Find more information/studies on obesity, diabetes, hypertension and dementia right here.
 

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.