Nutrition and health

Objectives:
Is there a relationship between the levels of vitamin C, vitamin E and β-carotene in the plasma and Alzheimer's disease risk?

Study design:
This review article included studies with data of levels of vitamin C, vitamin E and β-carotene in the plasma of Alzheimer's disease patients.

Results and conclusions:
The investigators found meta-analysis showed that, compared with the control group, the level of vitamin E in the plasma of Alzheimer's disease patients declined significantly [SMD = -1.49 μmol/L, 95% CI = -2.08 to -0.89 μmol/L, p 0.001].

However, no differences were determined in the levels of the plasma vitamin C and β-carotene between the two groups [vitamin C: SMD = -1.43 μmol/L, 95% CI = -3.05 to 0.19 μmol/L, p = 0.083 and β-carotene: SMD = -0.61 μmol/L, 95% CI = -1.40 to 0.18 μmol/L, p = 0.131].

The investigators concluded increasing vitamin E level in the plasma through vitamin E riched diet is useful to prevent Alzheimer's disease. However, it is not yet believed the beneficial role on Alzheimer's disease to increase vitamin C and β-carotene.

Original title:
Meta-analysis of vitamin C, vitamin E and β-carotene levels in the plasma of Alzheimer's disease patients by Dong R, Yang Q, […], Zhao H.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30081996  

Additional information of El Mondo:
Find more information/studies on vitamin E, C, β-carotene and dementia right here.
 

Objectives:
Although several studies have been conducted on the association of vitamins with glaucoma, it is often noticed that the results are conflicting leaving physicians and patients in doubt about the effect of vitamins on glaucoma. Therefore, this review article has been conducted.

Does dietary vitamin intake reduce risk of the eye disease glaucoma? 

Study design:
This review article included 5 cohort studies with a total of 940 open-angle glaucoma (OAG) cases and 123,697 controls (persons without open-angle glaucoma).

Results and conclusions:
The investigators found a significantly reduced risk of 55% [pooled OR = 0.45, 95% CI = 0.30-0.68, I2 = 0%] for open-angle glaucoma for dietary intake of vitamin A.

The investigators found a significantly reduced risk of 61% [pooled OR = 0.39, 95% CI = 0.23-0.67, I2 = 0%] for open-angle glaucoma for dietary intake of vitamin C.

The investigators found a significantly reduced risk of 61% [pooled OR = 0.39, 95% CI = 0.22-0.70, I2 = 0%] for open-angle glaucoma for dietary intake of green leafy vegetables (a source for vitamin A, C and nitrate).

The investigators concluded dietary intake of vitamin A, C and green leafy vegetables show a beneficial association with the eye disease open-angle glaucoma.

Original title:
The Effect of Vitamins on Glaucoma: A Systematic Review and Meta-Analysis by Ramdas WD, Schouten JSAG and Webers CAB.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5872777/

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

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 associations of various dietary or circulating antioxidants with the risk of all-cause mortality in the general population have not been established yet. Therefore, this review article has been conducted.

Do dietary or circulating antioxidants reduced risk of all-cause mortality in the general population?

Study design:
This review article included 41 prospective observational studies with a total of 507,251 participants and 73,965 cases of all-cause mortality.

Results and conclusions:
The investigators found for the highest compared with the lowest category of circulating total carotenes concentrations a significantly reduced risk of 40% [RR = 0.60, 95% CI = 0.46 to 0.74] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating vitamin C concentrations a significantly reduced risk of 39% [RR = 0.61, 95% CI = 0.53 to 0.69] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating selenium concentrations a significantly reduced risk of 38% [RR = 0.62, 95% CI = 0.45 to 0.79] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating β-carotene concentrations a significantly reduced risk of 37% [RR = 0.63, 95% CI = 0.57 to 0.70] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating α-carotene concentrations a significantly reduced risk of 32% [RR = 0.68, 95% CI = 0.58 to 0.78] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating total carotenoids concentrations a significantly reduced risk of 32% [RR = 0.68, 95% CI = 0.56 to 0.80] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating lycopene concentrations a significantly reduced risk of 25% [RR = 0.75, 95% CI = 0.54 to 0.97] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of circulating α-tocopherol concentrations a significantly reduced risk of 16% [RR = 0.84, 95% CI = 0.77 to 0.91] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of total carotenoids a significantly reduced risk of 24% [RR = 0.76, 95% CI = 0.66 to 0.85] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of total antioxidants a significantly reduced risk of 23% [RR = 0.77, 95% CI = 0.73 to 0.81] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of selenium a significantly reduced risk of 21% [RR = 0.79, 95% CI = 0.73 to 0.85] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of α-carotene a significantly reduced risk of 21% [RR = 0.79, 95% CI = 0.63 to 0.94] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of β-carotene a significantly reduced risk of 18% [RR = 0.82, 95% CI = 0.77 to 0.86] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of vitamin C a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.83 to 0.94] for all-cause mortality.  

The investigators found for the highest compared with the lowest category of dietary intakes of total carotenes a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.81 to 0.97] for all-cause mortality.  

The investigators found for the highest compared with the lowest category a nonsignificant inverse association between dietary zinc, zeaxanthin, lutein and vitamin E and all-cause mortality risk.

The investigators found in nonlinear dose-response meta-analyses a linear inverse association in the analyses of dietary β-carotene and total antioxidant capacity, as well as in the analyses of circulating α-carotene, β-carotene, selenium, vitamin C and total carotenoids.

The investigators found the association appeared to be U-shaped in the analyses of serum lycopene and dietary vitamin C.

The investigators concluded that a diet with high antioxidant properties reduces the risk of all-cause mortality. These findings confirm current recommendations that promote higher intake of antioxidant-rich foods such as fruit and vegetables.

Original title:
Dietary Antioxidants, Circulating Antioxidant Concentrations, Total Antioxidant Capacity, and Risk of All-Cause Mortality: A Systematic Review and Dose-Response Meta-Analysis of Prospective Observational Studies by Jayedi A, Rashidy-Pour A, […], Shab-Bidar S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30239557

Additional information of El Mondo:
Find more information/studies on meta-analysis/cohort studies, nutrients, antioxidants and elderly right here.

Objectives:
Low carbohydrate diets, which restrict carbohydrate in favour of increased protein or fat intake, or both, are a popular weight-loss strategy. However, the long-term effect of carbohydrate restriction on mortality is controversial and could depend on whether dietary carbohydrate is replaced by plant-based or animal-based fat and protein. Therefore, this review article has been conducted.

Is there a relationship between carbohydrate diet and all-cause mortality?

Study design:
This review article included 8 cohort studies with a total of 432,179 participants, of which 40,181 deaths.

Results and conclusions:
The investigators found in the meta-analysis of 8 cohort studies, low carbohydrate consumption (40 En%) significantly increased all-cause mortality risk with 20% [pooled HR = 1.20, 95% CI = 1.09-1.32].

The investigators found in the meta-analysis of 8 cohort studies, high carbohydrate consumption (>70 En%) significantly increased all-cause mortality risk with 23% [pooled HR = 1.23, 95% CI = 1.11-1.36].

The investigators found, however, results varied by the source of macronutrients: all-cause mortality increased when carbohydrates were exchanged for animal-derived fat or protein [HR = 1.18, 95% CI = 1.08-1.29] and all-cause mortality decreased when the substitutions were plant-based [HR = 0.82, 95% CI = 0.78-0.87].

The investigators found a U-shaped relationship between carbohydrate intake and all-cause mortality, with minimum risk observed with 50-55% of energy from carbohydrate.

The investigators concluded that both high (>70 En%) and low percentages of carbohydrate diets (40 En%) are associated with increased all-cause mortality, with minimal risk observed at 50-55 En% carbohydrate intake. Low carbohydrate dietary patterns favouring animal-derived protein and fat sources, from sources such as lamb, beef, pork and chicken, are associated with higher all-cause mortality, whereas those that favoured plant-derived protein and fat intake, from sources such as vegetables, nuts, peanut butter and whole-grain breads, are associated with lower all-cause mortality, suggesting that the source of food notably modifies the association between carbohydrate intake and all-cause mortality.

Original title:
Dietary carbohydrate intake and mortality: a prospective cohort study and meta-analysis by Seidelmann SB, Claggett B, […], Solomon SD.

Link:
https://www.thelancet.com/journals/lanpub/article/PIIS2468-2667(18)30135-X/fulltext

Additional information of El Mondo:
Find more information/studies on meta-analysis/cohort studies, carbohydrates and elderly right here.

The most easy way to follow a diet with 50-55 En% carbohydrates is to choose only meals/products with 50-55 En% carbohydrates.
However, the most practical way to follow a diet with 50-55 En% carbohydrates is all meals/products that you eat on a daily basis should contain on average 50-55 En% carbohydrates. Check here which products contain 50-55 En% carbohydrates.
 

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:
Oxidative stress has been found to be implicated in the development of Alzheimer's disease (AD). Therefore, this review article has been conducted.

Is there an association between selenium level in the brain and Alzheimer’s disease? 

Study design:
This review article included 14 studies with 40 observations on selenium concentrations in Alzheimer’s disease and control brains (persons without Alzheimer’s disease).

The effect size as standardized mean difference (SMD) was generated using review manager 5.3.

The funnel plot with Egger's [p = 0.88] and Begg's tests [p = 0.24] detected no significant publication bias.

Results and conclusions:
The investigators found random-effects meta-analysis indicated a decrease [SMD = - 0.42] in brain tissue selenium levels in patients with Alzheimer’s disease as compared to non-Alzheimer’s disease controls.
The results of sensitivity analysis indicated that no single study/observation had significantly influenced the overall outcome.

The investigators found the subgroup meta-analysis demonstrated that the selenium levels were decreased in the temporal, hippocampal and cortex regions of the brains in patients with Alzheimer’s disease.
The results of sensitivity analysis indicated that no single study/observation had significantly influenced the overall outcome.

The investigators concluded there is consolidated evidence for a significant decrease of selenium status in Alzheimer’s disease brains compared to controls (persons without Alzheimer’s disease). In line with the evidence supporting selenium's antioxidant role and the involvement of oxidative stress in Alzheimer’s disease development, these findings support new therapeutic strategies aimed at brain tissue selenium homeostasis in Alzheimer’s disease.

Original title:
Brain Selenium in Alzheimer's Disease (BRAIN SEAD Study): a Systematic Review and Meta-Analysis by Varikasuvu SR, Prasad VS, [...], Manne M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30171594

Additional information of El Mondo:
Find more information/studies on selenium and Alzheimer’s disease right here.
 

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:
Total dietary fat intake might influence the risk of fracture; however, conflicting findings have been reported to date. Therefore, this review article has been conducted.

Is there an association between dietary fat intake and risk of fracture?

Study design:
This review article included 6 observational studies.

Results and conclusions:
The investigators found no significant association between total dietary fat intake and risk of fracture [pooled effect size = 1.31, 95% CI = 0.95-1.79, p = 0.09].

The investigators found dietary saturated fat intake significantly increased risk of fracture with 79% [pooled effect size = 1.79, 95% CI = 1.05-3.03, p = 0.03].

The investigators found dietary monounsaturated fatty acids (MUFAs) intake derived from animal sources significantly increased risk of fracture with 129% [pooled effect size = 2.29, 95% CI = 1.50-3.50, p 0.0001].

The investigators concluded that both dietary saturated fat and monounsaturated fatty acids (MUFAs) intake derived from animal sources increase risk of fracture.

Original title:
Dietary fat, saturated fatty acid, and monounsaturated fatty acid intakes and risk of bone fracture: a systematic review and meta-analysis of observational studies by Mozaffari H, Djafarian K, […], Shab-Bidar S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29947872

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

A diet high in saturated fat is a diet that is largely made up of meals/products with more than 10 En% saturated fat. Practically, this means that all meals/products that you eat on a daily basis should on average contain more than 10 En% saturated fat. Check here which products contains more than 10 En% saturated fat.
More than 10 En% saturated fat means that the total amounts of saturated fat make up for more than 10% of the total kcal of the diet.
 

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:
Is there an association between consumption of food groups and the occurrence of age-related macular degeneration (AMD)?

Study design:
This review article included 26 prospective cohort studies with a total of 211,676 subjects and 7,154 cases of age-related macular degeneration.

Results and conclusions:
The investigators found no significant association between age-related macular degeneration and vegetables, fruit, nuts, grains, dairy products or dietary fats such as oils, butter and margarine when comparing the highest vs. the lowest consumption.

The investigators found a significantly reduced risk of 18% for total age-related macular degeneration [RR = 0.82, 95% CI = 0.75-0.90, p  0.05] when comparing the highest vs. the lowest fish consumption.

The investigators found a significantly reduced risk of 16% for early age-related macular degeneration [RR = 0.84, 95% CI = 0.73-0.97, p  0.05] when comparing the highest vs. the lowest fish consumption.

The investigators found a significantly reduced risk of 21% for late age-related macular degeneration [RR = 0.79, 95% CI = 0.70-0.90, p  0.05], when comparing the highest vs. the lowest fish consumption. 

The investigators found a significantly increased risk of 17% for early age-related macular degeneration [RR = 1.17, 95% CI = 1.02-1.34] when comparing the highest vs. the lowest meat consumption. However, no association was found for late age-related macular degeneration.

The investigators found a significantly increased risk of 20% for early age-related macular degeneration [RR = 1.20, 95% CI = 1.04-1.39] when comparing the highest vs. the lowest alcohol consumption.

The investigators concluded that high fish consumption decreases risk of age-related macular degeneration, while high intake of meat and alcohol increases risk of age-related macular degeneration.

Original title:
Food groups and risk of age-related macular degeneration: a systematic review with meta-analysis by Dinu M, Pagliai G, […], Sofi F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29978377

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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

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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

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Objectives:
Cardiovascular risk factors are closely linked with dementia risk, but whether heart disease predisposes to dementia is uncertain. Therefore, this review article has been conducted.

Does heart disease increase risk of dementia?

Study design:
This review article included 16 studies (1,309,483 individuals) regarding coronary heart disease and 7 studies (1,958,702 individuals) about heart failure.

Results and conclusions:
The investigators found that a history of coronary heart disease was associated with a 27% increased risk of dementia [pooled relative risk = 1.27, 95% CI = 1.07-1.50, I2 = 80%].

The investigators found that a history of heart failure was associated with a 60% increased dementia risk [pooled relative risk = 1.60, 95% CI = 1.19-2.13, I2 = 59%].

The investigators found among 9 prospective population-based cohort studies, a significantly increased risk of 26% for dementia among patients with coronary heart disease [pooled relative risk = 1.26, 95% CI = 1.06-1.49, I2 = 0%].
Significantly means that there is an association with a 95% confidence.

The investigators found among 4 prospective population-based cohort studies, a significantly increased risk of 80% for dementia among patients with heart failure [pooled relative risk = 1.80, 95% CI = 1.41-2.31, I2 = 0%].
Significantly means it can be said with a 95% confidence that heart failure really increased the risk of getting dementia with 80%. 

The investigators concluded that both coronary heart disease and heart failure are associated with an increased risk of dementia.

Original title:
Coronary heart disease, heart failure, and the risk of dementia: A systematic review and meta-analysis by Wolters FJ, Segufa RA, […], Sedaghat S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29494808

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Objectives:
Inflammatory markers are often elevated in patients with dementia, including Alzheimer's disease (AD). However, it remains unclear whether inflammatory markers are associated with the risk of developing dementia. Therefore, this review article has been conducted.

Do inflammatory markers increase risk of dementia and Alzheimer's disease (AD)?

Study design:
This review article included 13 studies in 6 countries.

Results and conclusions:
The investigators found a significantly increased risk of 37% [HR = 1.37, 95% CI = 1.05-1.78] for all-cause dementia for the highest vs. lowest quantile of C-reactive protein. However, this increased risk was not significant for Alzheimer's disease.

The investigators found a significantly increased risk of 40% [HR = 1.40, 95% CI = 1.13-1.73] for all-cause dementia for the highest vs. lowest quantile of interleukin-6. However, this increased risk was not significant for Alzheimer's disease.

The investigators found a significantly increased risk of 54% [HR = 1.54, 95% CI = 1.14-2.80] for all-cause dementia for the highest vs. lowest quantile of α1-antichymotrypsin. However, this increased risk was not significant for Alzheimer's disease.

The investigators found a significantly increased risk of 40% [HR = 1.40, 95% CI = 1.03-1.90] for all-cause dementia for the highest vs. lowest quantile of lipoprotein-associated phospholipase A2 activity. However, this increased risk was not significant for Alzheimer's disease.

The investigators concluded that several inflammatory markers are associated with an increased risk of all-cause dementia; however, these markers are not specific for Alzheimer's disease. Whether inflammatory markers closely involved in Alzheimer's disease pathology are associated with the risk of Alzheimer's disease remains to be elucidated.

Original title:
Inflammatory markers and the risk of dementia and Alzheimer's disease: A meta-analysis by Darweesh SKL, Wolters FJ, […], Hofman A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29605221

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Objectives:
β-amyloid (Aβ) accumulates abnormally to senile plaque which is the initiator of Alzheimer's disease (AD). As one of the Aβ-degrading enzymes, insulin-degrading enzyme (IDE) remains controversial for its protein level and activity in Alzheimer's brain. Therefore, this review article has been conducted.

Is there an association between insulin-degrading enzyme protein level and risk of Alzheimer's disease (AD)?

Study design:
This review article included 7 studies for IDE protein level (Alzheimer's disease cases = 293 and controls (persons without Alzheimer's disease)  = 126), 3 for mRNA level (Alzheimer's disease cases = 138 and controls = 81) and 3 for enzyme activity (Alzheimer's disease cases = 123 and controls = 75).

Results and conclusions:
The investigators found the insulin-degrading enzyme protein level was significantly lower in Alzheimer's disease patients than in controls [SMD = -0.47, 95% CI = -0.69 to -0.24, p 0.001].
But insulin-degrading enzyme mRNA and enzyme activity had no significant difference [SMD = 0.02, 95% CI = -0.40 to 0.43 and SMD = 0.06, 95% CI = -0.41 to 0.53, respectively].

The investigators found in subgroup analyses (to get more information) that insulin-degrading enzyme protein level was decreased in both cortex and hippocampus of Alzheimer's disease patients [SMD = -0.43, 95% CI = -0.71 to -0.16, p = 0.002 and SMD = -0.53, 95% CI = -0.91 to -0.15, p = 0.006 respectively].
However, insulin-degrading enzyme mRNA was higher in cortex of Alzheimer's disease patients [SMD = 0.71, 95% CI = 0.14 to 1.29, p = 0.01] but not in hippocampus [SMD = -0.26, 95% CI [= -0.58 to 0.06].

The investigators concluded that Alzheimer's disease patients have lower insulin-degrading enzyme protein level. Further relevant studies are still needed to verify whether insulin-degrading enzyme is one of the factors affecting Aβ abnormal accumulation and throw new insights for Alzheimer's disease detection or therapy.

Original title:
Characteristics of Insulin-degrading Enzyme in Alzheimer's Disease: A Meta-analysis by Zhang H, Liu D, […], Zhou H.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29357797

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Objectives:
Is there a dose-response association between serum 25(OH)D (vitamin D level in blood) and risk of dementia and Alzheimer's disease (AD)?

Study design:
This review article included 7 prospective cohort studies and 1 retrospective cohort study involving 1,953 cases of dementia and 1,607 cases of Alzheimer's disease among a total of 28,354 participants.

Results and conclusions:
The investigators found no association between vitamin D insufficiency (10-20 ng/mL) and risk of dementia [pooled HR = 1.09, 95% CI = 0.95 to 1.24].
No association because RR of 1 was found in the 95% CI of 0.95 to 1.24. RR of 1 means no risk/association.

The investigators found no association between vitamin D insufficiency (10-20 ng/mL) and risk of Alzheimer's disease [pooled HR = 1.19, 95% CI = 0.96 to 1.41].

The investigators found vitamin D deficiency (10 ng/mL) significantly increased risk of dementia with 33% [pooled HR = 1.33, 95% CI = 1.08 to 1.58].
Significantly means it can be said with a 95% confidence that vitamin D deficiency really increased the risk of getting dementia with 33%. 

The investigators found vitamin D deficiency (10 ng/mL) non-significantly increased risk of Alzheimer's disease with 31% [pooled HR = 1.31, 95% CI = 0.98 to 1.65].

The investigators found lower risk of dementia was observed at serum 25(OH)D of 25 ng/mL, whereas the risk of Alzheimer's disease decreased continuously along with the increase of serum 25(OH)D up to 35 ng/mL.

The investigators concluded that vitamin D (serum 25(OH)D) levels of 25 to 35 ng/mL decrease risk of dementia and Alzheimer's disease. However, there is no conclusive evidence regarding serum 25(OH)D levels of >35 ng/mL.

Original title:
Vitamin D status and risk of dementia and Alzheimer's disease: A meta-analysis of dose-response by Jayedi A, Rashidy-Pour A and Shab-Bidar S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29447107

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Objectives:
Dairy product consumption may affect the risk of hip fracture, but previous studies have reported inconsistent findings. Therefore, this review article has been conducted.

Does consumption of dairy products reduce risk of hip fracture?

Study design:
This review article included 10 cohort studies (with a total of 8,613 hip fracture events and 363,557 participants. The length of follow-up ranged from 3 to 22 years) and 8 case-control studies (3,815 hip fracture cases and 6,415 controls/subjects without hip fracture).

Results and conclusions:
The investigators found in cohort studies no association between a high milk consumption and hip fracture risk [pooled RR = 0.91, 95% CI = 0.74-1.12, I2 = 75.0%, p  0.01].
There were no significant changes to the results after using the trim-and-fill method when including 4 missing articles [adjusted random effects summary RR = 1.06, 95% CI = 0.91-1.23].

The investigators found, however, case-control studies indicated that participants in the highest categories of milk consumption had a 29% reduction in the risk of hip fracture [OR = 0.71, 95% CI = 0.55-0.91, I2 = 54%, p = 0.04].
There were no significant changes to the results after using the trim-and-fill method when including 1 missing article [adjusted random effects summary OR = 0.74, 95% CI = 0.57-0.97].

The investigators found in cohort studies no association between a high total dairy consumption and hip fracture risk [pooled RR = 1.02, 95% CI = 0.93-1.12]. No association because RR of 1 was found in the 95% CI of 0.93 to 1.12. RR of 1 means no risk/association.

The investigators found cohort studies indicated that participants in the highest categories of yoghurt consumption had a 25% reduction in the risk of hip fracture [RR = 0.75, 95% CI = 0.66-0.86].
 

The investigators found cohort studies indicated that participants in the highest categories of cheese consumption had a 32% reduction in the risk of hip fracture [RR = 0.68, 95% CI = 0.61-0.77].

The investigators found the summary RR for an increased milk consumption of 200 g/day was 1.00 [95% CI = 0.94-1.07, I2 = 87%, p heterogeneity  0.01] among cohort studies.

The investigators found in cohort studies there was a nonlinear positive association between milk consumption and hip fracture risk [p nonlinearity  0.01], with a rapid increase in risk when milk consumption increased from 0 to 600 g/d. However, there was no further increase in risk with milk consumption between 600 and 1200 g/d.

The investigators found in case-control studies there was a nonlinear association between milk consumption and hip fracture risk [p nonlinearity = 0.28], with a reduction in risk with milk consumption of 200-600 g/d. However, the confidence intervals were wide for all outcomes.

The investigators concluded that a high consumption of yogurt and cheese is associated with a lower risk of hip fracture in cohort studies.

Original title:
Dairy product consumption and risk of hip fracture: a systematic review and meta-analysis by Bian S, Hu J, [...], Ma J.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5778815/

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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

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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.

Objectives:
Does exercise training delay the decline in cognitive function among individuals who are at risk of/or have Alzheimer's disease?  

Study design:
This review article included 19 controlled studies with 23 interventions including 1,145 subjects with a mean age of 77.0 ± 7.5.
The studies included an exercise-only intervention and a nondiet, nonexercise control group and reported pre- and post-intervention cognitive function measurements.

Most subjects were at risk of Alzheimer's disease because they had mild cognitive impairment (64%) or a parent diagnosed with Alzheimer's disease (1%) and 35% presented with Alzheimer's disease.

Exercise interventions were performed 3.4 ± 1.4 days per week at moderate intensity (3.7 ± 0.6 metabolic equivalents) for 45.2 ± 17.0 minutes per session for 18.6 ± 10.0 weeks and consisted primarily of aerobic exercise (65%).

Results and conclusions:
The investigators found overall, there was a modest favourable effect of exercise on cognitive function [d+ = 0.47, 95% CI = 0.26 to 0.68].

The investigators found within-group analyses revealed that exercise improved cognitive function [d+w = 0.20, 95% CI = 0.11 to 0.28], whereas cognitive function declined in the control group [d+w = -0.18, 95% CI = -0.36 to 0.00].

The investigators found within-group analyses revealed that aerobic exercise had a moderate favourable effect on cognitive function [d+w = 0.65, 95% CI = 0.35 to 0.95), but other exercise types did not [d+w = 0.19, 95% CI = -0.06 to 0.43].

The investigators concluded that exercise training (3.4 days per week at moderate intensity for 45.2 minutes per session during 18.6 weeks) delays the decline in cognitive function that occurs in individuals who are at risk of/or have Alzheimer's disease, with aerobic exercise having the most favourable effect. Additional randomized controlled clinical trials that include objective measurements of cognitive function are needed to confirm these findings.

Original title:
Can Exercise Improve Cognitive Symptoms of Alzheimer's Disease? A Meta-Analysis by Panza GA, Taylor BA, […], Pescatello LS.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29363108

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Metabolic Equivalents (METs) are commonly used to express the intensity of physical activities.
MET is the ratio of a person's working metabolic rate relative to their resting metabolic rate.
One MET is defined as the energy cost of sitting quietly and is equivalent to a caloric consumption of 1 kcal/kg/hour.