Nutrition and health

Objectives:
Dementia is a chronic progressive neurodegenerative disease that can lead to disability and death in humans, but there is still no effective prevention and treatment. Due to the neuroprotective effects of vitamin E, a large number of researchers have explored whether vitamin E can reduce the risk of dementia. Some researchers believe that vitamin E can reduce the risk of dementia, while others hold the opposite conclusion. Therefore, this review article has been conducted.

Do high intakes of diet or vitamin E supplements reduce the risk of dementia?

Study design:
This review article included 13 cohort studies (46,968 participants and 6,046 dementia patients after 4-23 years of follow-up) and 2 case-control studies with (3,157 controls and 3,459 patients).
The studies included in this meta-analysis (review article) were published between 1983 and 2022.
The literary NOS quality score ranged from 6 to 8.
There was no publication bias.

Results and conclusions:
The investigators found a high intake of diet or vitamin E supplements significantly decreased the risk of dementia by 21% [OR = 0.79, 95% CI = 0.70 to 0.88, I2 = 35.0%, p = 0.071].
This decreased risk was also significant in cohort studies [OR = 0.79, 95% CI = 0.69 to 0.89], dietary intake of vitamin E [OR = 0.78, 95% CI = 0.65 to 0.95], vitamin E supplement [OR = 0.83, 95% CI = 0.73 to 0.94] and studies with NOS scores >7 [OR = 0.85, 95% CI = 0.75 to 0.97].

The investigators found a high intake of diet or vitamin E supplements significantly decreased the risk of Alzheimer's disease by 22% [OR = 0.78, 95% CI = 0.64 to 0.94, I2 = 36.9%, p = 0.123].
This decreased risk was also significant in cohort studies [OR = 0.77, 95% CI = 0.63 to 0.94].

The investigators found in sensitivity analysis the pooled ORs fluctuated within a certain range after deleting each study, indicating that the results of this meta-analysis were stable.

The investigators concluded high intakes of diet or vitamin E supplements reduce the risk of dementia. Therefore, the elderly can reduce the risk of dementia by appropriately increasing foods rich in vitamin E, but also pay attention to the toxic side effects of vitamin E. Although the results are reliable, they should be further validated by large RCTs.

Original title:
Association of vitamin E intake in diet and supplements with risk of dementia: A meta-analysis by Zhao R, Han X, [...], You H.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9376618/

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

Objectives:
Do plant-based diets improve age-related ocular outcomes among adults?

Study design:
This review article included 15 studies (n = 51,695 participants) assessed the impact of fish consumption, 8 studies (n = 28,753 participants) analyzed the effect of red meat intake and 3 studies (n = 7,723 participants) assessed the impact of omission of skim milk, poultry and non-meat animal products and the presence of disease incidence as indicated by age-related macular degeneration or cataract development.

Results and conclusions:
The investigators found in 15 studies (n = 51,695 participants) that regular consumption of fish significantly reduced the risk of age-related eye disease development among adults with 30% [odds ratio = 0.70, 95% CI = 0.62 to 0.79].
Significant means that there is an association with a 95% confidence.

The investigators found in 3 studies (n = 7,723 participants) that regular consumption of skim milk, poultry and non-meat animal products significantly reduced the risk of age-related eye disease development among adults with 30% [odds ratio = 0.70, 95% CI = 0.61 to 0.79].
Significant because odds ratio of 1 was not found in the 95% CI of 1.07 to 1.72. Odds ratio of 1 means no risk/association.

The investigators found in 8 studies (n = 28,753 participants) that regular consumption of red meat significantly increased the risk of age-related eye disease development among adults with 41% [odds ratio = 1.41, 95% CI = 1.07 to 1.86].

The investigators concluded that regular consumption of both fish and skim milk, poultry and non-meat animal products reduce the risk of age-related eye disease development among adults, while regular consumption of red meat increases the risk of age-related eye disease development among adults. Results suggest a need for more initiatives promoting a healthy and balanced diet.

Original title:
Linkage between a plant-based diet and age-related eye diseases: a systematic review and meta-analysis by Cirone C, Cirone KD and Malvankar-Mehta MS.

Link:
https://pubmed.ncbi.nlm.nih.gov/36102832/

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

In practice, regular fish consumption corresponds to at least twice (100-150g per time) a week.
 

Objectives:
Although recent studies comparing various dosages and intervals of vitamin D supplementation have been published, it is yet to be elucidated whether there is an appropriate dose or interval to provide benefit regarding fracture risk. Therefore, this review article has been conducted.

What are the putative beneficial effects of vitamin D supplements on fractures and falls according to various dosages and intervals?

Study design:
This review article included 32 RCTs with a total of 104,363 patients, with a median of 3,162 patients per study (range 46 to 36,282).
The median daily dose of cholecalciferol (D3) was 800 IU/day and 8 studies reported 800 IU/day, 15 studies reported 800 to 1,000 IU/day and 9 studies reported >1,000 IU/day.
The median follow-up duration was 24 months (range 9 to 120) and the median age was 72 years (range 53 to 85).

Results and conclusions:
The investigators found vitamin D3 supplementation with daily dose of 800 to 1,000 IU was significantly associated with a lower risk of 13% for osteoporotic fracture [pooled relative risk = 0.87, 95% CI = 0.78 to 0.97, I2 = 23.5%] while studies with 800 or >1,000 IU/day did not.

The investigators found vitamin D3 supplementation with daily dose of 800 to 1,000 IU was significantly associated with a lower risk of 9% for fall [pooled relative risk = 0.91, 95% CI = 0.85 to 0.98, I2 = 70.9%] while studies with 800 or >1,000 IU/day did not.

The investigators found daily administration of vitamin D3 was associated with the reduced risk of falls, while intermittent dose was not.
Also, patients with vitamin D deficiency showed a significant risk reduction of falls after vitamin D3 supplementation.

The investigators concluded that daily vitamin D3 dose of 800 to 1,000 IU (20-25 mcg) during 24 months is the most probable way to reduce the fracture and fall risk among elderly. Further studies designed with various regimens and targeted vitamin D levels are required to elucidate the benefits of vitamin D supplements.

Original title:
Effect of Vitamin D Supplementation on Risk of Fractures and Falls According to Dosage and Interval: A Meta-Analysis by Kong SH, Jang HN, […], Shin CS.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9081312/

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

Objectives:
In postmenopausal women, vitamin D deficiency (as defined by the circulating level of 25(OH)D being below 20 ng/mL (50 nmol/L)) is a regular occurrence. The effect of vitamin D supplementation on the muscle function of postmenopausal women has been controversial. Therefore, this review article has been conducted.

Does vitamin D supplementation enhance the muscular strength and mobility of postmenopausal women?

Study design:
This review article included 19 RCTs between 2003 and 2021, with 5,398 participants.
The sample size of the RCTs included in multiple countries ranges from 20 to 2,347. Furthermore, the duration of vitamin D supplementation ranged from 3 to 60 months.
Vitamin D3 was applied in 12 of the 19 retrieved trials, whose dosages ranged from 400 IU/day to 300,000 IU (10 tot 7500 mcg vitamin D3) in a single oral dose.
Visual inspection of the funnel plot and Egger’s linear regression test revealed no indication of publication bias in the meta-analysis of vitamin D supplementation on handgrip strength.

Results and conclusions:
The investigators found meta-analysis of 9 RCTs (1,997 participants supplemented with vitamin D and 2,232 participants as the control group (vitamin D in low dosage or placebo)), showed that vitamin D supplementation significantly improved handgrip strength in postmenopausal women [WMD = 0.876 kg, 95% CI = 0.180 to 1.571, p = 0.014, I2 = 68.5%, p = 0.001].
Moreover, according to subgroup analysis, vitamin D supplementation substantially raised handgrip strength when compared to baseline blood vitamin D levels >75 nmol/L (30 ng/ml) [WMD = 0.478 kg, 95% CI = 0.963 to 1.918, p = 0.003], without calcium [WMD = 1.931 kg, 95% CI = 0.166 to 3.697, p = 0.032] and subject to an age of more than 60 [WMD = 1.116 kg, 95% CI = 0.433 to 1.799, p = 0.001].

The investigators concluded that 400 IU/day to 300,000 IU vitamin D supplementation during 3 to 60 months improves handgrip strength in postmenopausal women over 60 years of age who are without calcium supplementation or whose baseline vitamin D is >75 nmol/L (30 ng/mL). These findings show that future trials should focus on determining the ideal dosage and duration and taking into account the several factors that may impair muscle performance, such as exercise, calcium consumption, frailty, a history of falls or fractures and baseline vitamin D status and the relationship between muscle function and/or strength with muscle composition.

Original title:
Vitamin D Supplementation Improves Handgrip Strength in Postmenopausal Women: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Zhang JL, Poon CCW, […], Zhang Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9199366/

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

Objectives:
Data from studies support a beneficial effect of carotenoids and vitamins on an age-related macular degeneration (AMD) risk. However, studies on the relations between blood levels of these nutrients and AMD are limited and provided conflicting results. Therefore, this review article has been conducted.

Does a higher concentration of carotenoids (lutein/zeaxanthin, β-carotene, β-cryptoxanthin, lycopene) and vitamins in blood reduce age-related macular degeneration risk?

Study design:
This review article included 9 studies (1 cohort, 4 case-control and 4 cross-sectional studies) involving 15,674 participants and 2,077 AMD cases (persons with age-related macular degeneration).  
There was no evidence of publication bias.

Results and conclusions:
The investigators found in the meta-analysis that high blood lutein/zeaxanthin level significantly reduced risk of age-related macular degeneration with 47% [OR = 0.53, 95% CI = 0.40 to 0.72, p 0.001, I2 = 43.3%, p = 0.079], compared to those with low level.
Results stratified by factors yielded similar results to the main analysis.

The investigators found in the meta-analysis that high blood β-carotene level significantly reduced risk of age-related macular degeneration with 52% [OR = 0.48, 95% CI = 0.28 to 0.84, p = 0.01, I2 = 71.7%, p = 0.003], compared to those with low level.
A subgroup analysis by geographic region showed that the significant inverse association between blood β-carotene levels and risk of age-related macular degeneration was only found among the Asians.

The investigators found in the meta-analysis that high blood β-cryptoxanthin level significantly reduced risk of age-related macular degeneration with 52% [OR = 0.48, 95% CI = 0.23 to 1.00, p = 0.04, I2 = 83.5%, p 0.001], compared to those with low level.
In stratified analyses, no significant difference was observed for any subgroups.

The investigators found in the meta-analysis that high blood lycopene level significantly reduced risk of age-related macular degeneration with 30% [OR = 0.70, 95% CI = 0.54 to 0.90, p = 0.006, I2 = 0.0%, p = 0.67], compared to those with low level.

The investigators found in the meta-analysis that high blood α-tocopherol (vitamin E) level significantly reduced risk of age-related macular degeneration with 50% [OR = 0.50, 95% CI = 0.31 to 0.81, p = 0.005, I2 = 34.4%, p = 0.19], compared to those with low level.

The investigators found sensitivity analyses, that excluded one study at a time, did not change the statistical significance or the direction of the present findings, corroborating the robustness of the results.

The investigators concluded that there is a protective effect of higher concentration of carotenoids (lutein/zeaxanthin, β-carotene, β-cryptoxanthin, lycopene) and vitamin E in blood against age-related macular degeneration risk, which provides further evidence of the associations between carotenoid and vitamin status and the risk of age-related eye problems. Further randomized clinical trials are necessary for Asians to confirm such associations and to provide the most reliable direct information to base public health recommendations for age-related eye disease prevention by nutritional supplementation with carotenoids and vitamins.

Original title:
The Associations of Plasma Carotenoids and Vitamins With Risk of Age-Related Macular Degeneration: Results From a Matched Case-Control Study in China and Meta-Analysis by Jiang H, Fan  Y, […], Ma L.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8873933/

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

High blood levels of beta-carotene can be obtained by consuming beta-carotene-rich foods and/or taking beta-carotene supplements.
 

Objectives:
While there is growing research interest in the effects of nutrition and exercise on delaying sarcopenia, the results are inconclusive and there is scarce information on regional patterns. Therefore, this review article has been conducted.

Do protein supplements combined with exercise improve extremity strength in healthy older adults with sarcopenia?

Study design:
This review article included 14 RCTs, involving a total of 888 healthy older adults (>60 years).

4 studies in Asian countries provided data on lower-extremity strength, involving 280 participants (138 in protein supplements + exercise group and 142 in exercise group).
Lower-extremity strength was assessed using knee extension (n = 3) or leg extension (n = 1).
The intervention period of all studies was 12 weeks.
The dosage of protein ranged from 3 g/d to 40 g/d.

Results and conclusions:
The investigators found in 4 studies in Asian countries a significant increase in the lower-extremity strength in the protein supplementation + exercise group compared to the exercise group, with a SMD of 0.24 [95% CI = 0.00 to 0.47, p = 0.048, I2 = 0.0%, p = 0.513].

The investigators concluded that protein supplements (3 g/d to 40 g/d during 12 weeks) combined with exercise (knee extension and leg extension) exerts superior benefit on lower-extremity strength in healthy older adults with sarcopenia in Asian countries, when compared to exercise alone or with a placebo. However, no additional benefits from protein supplementation are observed on upper-extremity strength, muscle mass and physical performance regardless of the regions. More well-designed RCTs with information on baseline and total protein intake for longer follow-up periods are warranted to evaluate the effectiveness of protein supplementation and exercise on the prevention and management of sarcopenia in healthy older adults.

Original title:
Effects of protein supplementation and exercise on delaying sarcopenia in healthy older individuals in Asian and non-Asian countries: A systematic review and meta-analysis by Li L, He Y, […], Liu X.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8808080/

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

Upper extremity is part of the body that includes the arm, wrist and hand.

Lower extremity refers to the part of the body from the hip to the toes.

Sarcopenia is a type of muscle loss (muscle atrophy) that occurs with aging and/or immobility. Sarcopenia can affect people in their 30s and beyond.
 

Objectives:
Can the biomarker miRNAs predict Alzheimer's disease?

Study design:
This review article included 10 studies containing 770 Alzheimer's disease and 664 normal controls (persons without Alzheimer's disease).

Results and conclusions:
The investigators found miRNAs presented excellent diagnostic performance and the overall sensitivity was 0.80 [95% CI = 0.75-0.83], specificity was 0.83 [95% CI = 0.78-0.87] and diagnostic odds ratio was 14 [95% CI = 11-19].

The investigators found subgroup analysis suggested that the Caucasian group and blood group showed a better performance in Alzheimer's disease diagnosis and the diagnostic odds ratio was 42 and 34, respectively.

The investigators concluded that miRNAs may be a promising biomarker for Alzheimer's disease.

Original title:
Blood circulating miRNAs as biomarkers of Alzheimer's disease: a systematic review and meta-analysis by Zhang YH, Bai SF and Yan JQ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31385521

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

Objectives:
Does alcohol consumption increase of risk of osteoporosis?

Study design:
This review article included  3 case control studies, 2 cohort studies and 1 cross-sectional study.

Results and conclusions:
The investigators found no association between consuming 0.5-1 drinks per day and the risk of developing osteoporosis [adjusted RR = 1.38, 95% CI = 0.90-2.12].
No association because RR of 1 was found in the 95% CI of 0.90 to 2.12. RR of 1 means no risk/association.

The investigators found compared with abstainers of alcohol, persons consuming 1-2 drinks per day had 1.34 times the risk of developing osteoporosis [adjusted RR = 1.34, 95% CI = 1.11-1.62].

The investigators found compared with abstainers of alcohol, persons consuming 2 drinks or more per day had 1.63 times the risk of developing osteoporosis [adjusted RR = 1.63, 95% CI = 1.01-2.65].

The investigators found a positive association between alcohol consumption and osteoporosis in the case-control studies [adjusted OR = 2.95, 95% CI = 1.78-4.90].

The investigators concluded there is a positive relationship between alcohol consumption, particularly 1 drink or more per day and osteoporosis.

Original title:
The effect of alcohol on osteoporosis: A systematic review and meta-analysis by Cheraghi Z, Doosti-Irani A, Almasi-Hashiani A, […], Mansournia MA.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30844616

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

Objectives:
Do older adults benefit from high protein intake (>0.8 g/kg body weight/day)?

Study design:
This review article included 12 cohort studies and 1 RCT.
Studies had an intervention duration of at least 6 months.

Results and conclusions:
The investigators found meta-analysis of the cohort studies showed that high vs low protein intake resulted in a statistically significant decrease of 11% for hip fractures [pooled HR = 0.89, 95% CI = 0.84 to 0.94, p 0.001, I2 = 0.0%, p = 0.614].
Sensitivity analyses showed that there was no single study affecting the overall estimate considerably.

The investigators concluded there is an association between a dietary protein intake above the current RDA of 0.8 g/kg body weight/day and a reduced hip fracture risk in older adults. In comparison with younger adults, the body of evidence from the included studies is not strong enough to increase the protein recommendation for older adults with respect to bone health.

Original title:
High Versus low Dietary Protein Intake and Bone Health in Older Adults: a Systematic Review and Meta-Analysis by Groenendijk I, den Boeft L , [...], de Groot LCPGM.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6704341/

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Find more information/studies on protein and elderly.

A protein intake higher than 0.8 g/kg body weight/day corresponds to a diet with a minimum of 11 En% protein. The easiest way to follow a diet with at least 11 En% protein is to choose only products that contain at least 11 En% protein. These products from the supermarket contain at least 11% En% protein.
 

Objectives:
Do low folate levels and vitamin B12 levels increase risk of depression among the aged people?

Study design:
This review article included both gender data of 11 folate-related (7,949 individuals) and 9 B12-related studies (6,308 individuals) and gender-specific data of 4 folate-related (3,409 individuals) and 3 B12-related studies (1,934 individuals).

Results and conclusions:
The investigators found low folate levels significantly increased risk of depression among the aged people with 23% [OR =1.23, 95% CI =1.07-1.43]. 

The investigators found low vitamin B12 levels significantly increased risk of depression among the aged people with 20% [OR =1.20, 95% CI =1.02-1.42]. 

The investigators found in subgroup analysis low vitamin B12 levels significantly increased risk of depression among the aged women with 33% [OR =1.33, 95% CI =1.02-1.74]. 

The investigators concluded both low folate levels and low vitamin B12 levels increase risk of depression among the aged people.

Original title:
Folate and B12 serum levels in association with depression in the aged: a systematic review and meta-analysis by Petridou ET, Kousoulis AA, [...], Stefanadis C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/26055921

Additional information of El Mondo:
Find more information/studies on vitamin B12, folate and elderly.
 

Objectives:
Findings from observational studies and clinical trials on the associations between vitamin E and dementia remain controversial. Therefore, this review article has been conducted.

Do low vitamin E levels increase risk of Alzheimer's disease (AD) or age-related cognitive deficits and mild cognitive impairment (MCI)?

Study design:
This review article included 31 studies.

Results and conclusions:
The investigators found individuals with Alzheimer's disease had lower circulatory concentrations of α-tocopherol (vitamin E) compared with healthy controls [SMD = -0.97, 95% CI = -1.27 to -0.68, p  0.00001].

The investigators found individuals with age-related cognitive deficits had lower circulatory concentrations of α-tocopherol (vitamin E) compared with healthy controls [SMD = -0.72, 95% CI = -1.12 to -0.32, p  0.0005].

The investigators found individuals with mild cognitive impairment had lower circulatory concentrations of α-tocopherol (vitamin E) compared with healthy controls [SMD = -0.72, 95% CI = -1.12 to -0.32, p  0.0005].

The investigators found levels of β-, γ- and δ-tocopherols did not significantly differ between groups of Alzheimer's disease and age-related cognitive deficits compared to controls.

The investigators concluded that lower α-tocopherol (vitamin E) levels have a strong association with Alzheimer's disease and mild cognitive impairment supporting evidence for the role of diet and vitamin E in Alzheimer's disease risk and age-related cognitive decline.

Original title:
A meta-analysis of peripheral tocopherol levels in age-related cognitive decline and Alzheimer's disease by Ashley S, Bradburn S and Murgatroyd C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31661399

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

Objectives:
Serum uric acid (SUA) accounts for about 50% of extracellular antioxidant activity, suggesting that hyperuricemia (an abnormally high level of uric acid in the blood) may have a protective role in diseases characterized by high levels of oxidative stress, such as osteoporosis. Therefore, this review article has been conducted.

Does a high serum uric acid level (also called hyperuricemia) increase bone mineral density (BMD)?

Study design:
This review article included 19 cross-sectional studies with a total of 55,859 participants.

Results and conclusions:
The investigators found in 6 studies that subjects with higher serum uric acid levels had significantly higher bone mineral density values for the spine [SMD = 0.29, 95% CI = 0.22-0.35, I2 = 47%].
Simple correlation analyses substantially confirmed this finding.

The investigators found in 7 studies that subjects with higher serum uric acid levels had significantly higher bone mineral density values for total hip [SMD = 0.29, 95% CI = 0.24-0.34, I2 = 33%].
Simple correlation analyses substantially confirmed this finding.

The investigators found in 6 studies that subjects with higher serum uric acid levels had significantly higher bone mineral density values for femoral neck [SMD = 0.25, 95% CI = 0.16-0.34, I2 = 71%].
Simple correlation analyses substantially confirmed this finding.

The investigators found in 3 studies that an increase of one standard deviation in serum uric acid levels significantly reduced risk of new fractures with 17% [HR = 0.83, 95% CI = 0.74-0.92, I2 = 0%].

The investigators found no significant differences between men and women, although data about women were limited.

The investigators concluded a high serum uric acid level is independently associated with higher bone mineral density values and a lower risk of fractures, supporting a protective role for uric acid in bone metabolism disorders.

Original title:
Hyperuricemia protects against low bone mineral density, osteoporosis and fractures: a systematic review and meta-analysis by Veronese N, Carraro S, […], Cereda E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27636234

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Objectives:
Do dietary intakes of soy, soy isoflavones and soy protein reduce risk of mortality from all causes, cancers and cardiovascular diseases?

Study design:
This review article included 23 prospective cohort studies with an overall sample size of 330,826 participants.

Results and conclusions:
The investigators found soy/soy products consumption significantly reduced risk of mortality from cancers with 12% [pooled relative risk = 0.88, 95% CI = 0.79 to 0.99, p = 0.03, I2 = 47.1%].

The investigators found soy/soy products consumption significantly reduced risk of mortality from cardiovascular diseases with 15% [pooled effect size = 0.85, 95% CI = 0.72 to 0.99, p = 0.04, I2 = 50.0%].

The investigators found such significant associations were also observed for all-cause mortality in some subgroups of the included studies, particularly those with higher quality.

The investigators found in addition, higher dietary intake of soy was associated with decreased risk of mortality from gastric, colorectal and lung cancers as well as ischemic cardiovascular diseases.

The investigators found participants in the highest category of dietary soy isoflavones intake had a 10% lower risk of all-cause mortality compared with those in the lowest category.

The investigators found that a 10-mg/day increase in dietary intake of soy isoflavones was associated with 7% and 9% decreased risk of mortality from all cancers and breast cancer, respectively.

The investigators found for each 5-g/day increase in consumption of soy protein a 12% reduction in breast cancer death.

The investigators found, however, dietary intake of soy protein was not significantly associated with all-cause and cardiovascular diseases mortality.

The investigators concluded that soy and its isoflavones consumption favorably influence risk of mortality. In addition, soy protein dietary intake is associated with a decreased risk in the mortality of breast cancer. These findings support the current recommendations to increase intake of soy for greater longevity.

Original title:
Soy, Soy Isoflavones, and Protein Intake in Relation to Mortality from All Causes, Cancers, and Cardiovascular Diseases: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies by Nachvak SM, Moradi S, […], Sadeghi O.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31278047

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Objectives:
Does a high blood homocysteine level increase risk of cognitive impairment, like Alzheimer's disease and vascular dementia?

Study design:
This review article included 28 prospective cohort studies with 2,557 cases (1,035 all-cause dementia, 530 Alzheimer's disease, 92 vascular dementia and >900 cognitive impairment without dementia (CIND)) among 28,257 participants.
 
The average follow-up period ranged from 2.7 to 35 years.

There was no clear evidence of publication bias with Begg's and Egger's tests for Alzheimer dementia [p = 0.806, 0.084, respectively].

Results and conclusions:
The investigators found there was a clear linear dose-response relationship between blood homocysteine concentration and risk of Alzheimer-type dementia [p > 0.05 for non-linearity].

The investigators found for every 5 μmol/L increase in blood homocysteine a significantly increased risk of 15% [pooled RR = 1.15, 95% CI = 1.04 to 1.26, I2 = 56.6%, n = 5] for Alzheimer-type dementia.
Sensitivity analysis showed similar results.

The investigators found due to the presence of publication bias and low statistical power, elevated levels of blood homocysteine were not appreciably associated with risk of all-cause, vascular dementia and cognitive impairment without dementia.

The investigators concluded every 5 μmol/L increase in blood homocysteine is linearly associated with a 15% increase in relative risk of Alzheimer-type dementia.

Original title:
Hyperhomocysteinemia and risk of incident cognitive outcomes: An updated dose-response meta-analysis of prospective cohort studies by Zhou F and Chen S.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30826501

Additional information of El Mondo:
Find more information/studies on Alzheimer disease.
 

Objectives:
Although intake of fruits and vegetables seemed to have a protective effect on bone metabolism, its effect on fractures remains uncertain. Therefore, this review article has been conducted.

Does intake of fruits and vegetables reduce risk of fractures?

Study design:
This review article included 6 cohort studies and 4 RCTs.
6 cohort studies included 225,062 participants (134,365 women and 90,697 men) aged 50 years or older. The participants’ follow-up time ranged from 2.8 years to 20 years.

Validated food frequency questionnaires (FFQs), 24-hour food recall (24h-R) and 7-day food record were used to evaluate fruit and vegetable intake.

Results and conclusions:
The investigators found in 5 cohort studies that intake of at least one serving of fruits and vegetables per day significantly reduced risk of hip fractures with 8% [pooled HR = 0.92, 95% CI = 0.87 to 0.98, I2 = 55.7%, p = 0.060] among participants aged 50 years or older.

The investigators found in 2 cohort studies that intake of at least one serving of fruits and vegetables per day significantly reduced risk of any fractures with 10% [pooled HR = 0.90, 95% CI = 0.86 to 0.96, I2 = 24.9%, p = 0.249] among participants aged 50 years or older.

The investigators found no association between the bone resorption marker CTx and 3 months of fruit and vegetable intake evaluated by 4 RCTs.

The investigators concluded that at least one serving of fruits and vegetables per day is associated with a lower risk of fractures among participants aged 50 years or older.

Original title:
Fruit and vegetable intake and bones: A systematic review and meta-analysis by Brondani JE, Comim FV, […], Premaor MO.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6544223/

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

Objectives:
Does a dietary low-ratio n-6/n-3 PUFA supplementation improve risk factors (such as fasting blood glucose, HbA1c) of diabetes?

Study design:
This review article included 11 RCTs.

No significant publication bias was observed for all blood glucose and other related indicators as suggested by Begg's test and Egger's test.

Results and conclusions:
The investigators found no significant effect of dietary low-ratio n-6/n-3 PUFA supplementation on:
-fasting blood glucose [WMD = 0.057 mmol/L, 95% CI = -0.090 to 0.204 mmol/L];
-insulin [WMD = -0.757 mIU/L, 95% CI = -2.419 to 0.904 mIU/L];
-insulin resistance index [WMD = -0.201, 95% CI = -0.566 to 0.165] and;
-glycosylated hemoglobin [WMD = -0.063%, 95% CI = -0.061 to 0.186%].

The investigators found subgroup analysis showed that the effect of dietary low-ratio n-6/n-3 PUFA on the reduction of the plasma insulin level in North America [WMD = -3.473 mIU/L, 95% CI = -5.760 to -1.185 mIU/L] was more obvious than that in Asian countries [WMD = -0.797 mIU/L, 95% CI = -2.497 to 0.902 mIU/L] and European countries [WMD = -0.063 mIU/L, 95% CI = -0.061 to 0.186 mIU/L].

The investigators found in the subgroup of diabetic subjects, dietary low-ratio n-6/n-3 PUFA supplementation significantly decreased plasma insulin level [WMD = -3.010 mIU/L, 95% CI = -5.371 to -0.648 mIU/L] and insulin resistance index [WMD = -0.460, 95% CI = -0.908 to -0.012].

The investigators found when the intervention period was longer than 8 weeks, dietary low-ratio n-6/n-3 PUFA supplementation significantly decreased the plasma insulin level [WMD = -2.782 mIU/L, 95% CI = -4.946 to -0.618 mIU/L].

The investigators concluded dietary low-ratio n-6/n-3 PUFA supplementation improves the glucose metabolism by reducing the insulin and insulin resistance in the diabetic patients. Dietary low-ratio n-6/n-3 PUFA supplementation also reduces the plasma insulin level when the supplementation duration is longer than 8 weeks.

Original title:
Effect of low-ratio n-6/n-3 PUFA on blood glucose: a meta-analysis by Li N, Yue H, […], Xu T.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31292599

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

Objectives:
The associations between dietary fat intake and cognitive function are inconsistent and inconclusive. Therefore, this review article has been conducted.

Is there a relationship between different types of fat intake and cognitive impairment?

Study design:
This review article included 9 prospective cohort studies covering a total of 23,402 participants.

Results and conclusions:
The investigators found compared with the lowest category of consumption, the highest category of saturated fat consumption significantly increased risk of cognitive impairment with 40% [RR = 1.40, 95% CI = 1.02-1.91].

The investigators found compared with the lowest category of consumption, the highest category of saturated fat consumption significantly increased risk of Alzheimer disease with 87% [RR = 1.87, 95% CI = 1.09-3.20].

The investigators found total and unsaturated fat dietary intakes were not statistically associated with cognitive outcomes with significant between-study heterogeneity.

The investigators concluded there is an increased risk between saturated fat consumption and both cognitive impairment and Alzheimer disease. Given the substantial heterogeneity in the sample size and methodology used across studies, the evidence presented here should be interpreted with caution.

Original title:
Dietary Fat Intake and Cognitive Function among Older Populations: A Systematic Review and Meta-Analysis by Cao GY, Li M, […], Xu B.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31062836

Additional information of El Mondo:
Find more information/studies on saturated fat intake, dementia and elderly right here.

A diet with a high saturated fat intake is a diet with >10 En% saturated fat.
>10 En% saturated fat means that the total amounts of saturated fat make up for >10% of the total kcal of the diet.
The easiest way to follow this diet is to choose only meals/products that also contain 10 En% saturated fat.
Check here which products contain >10 En% saturated fat.

A diet with a low saturated fat intake is a diet with 7 En% saturated fat.

Objectives:
No conclusive information is available about the association between dietary total antioxidant capacity (DTAC) and risk of mortality. Therefore, this review article has been conducted.

Does dietary total antioxidant capacity (DTAC) reduce risk of death from all-cause (all-cause mortality), cancer (cancer mortality) and cardiovascular diseases (CVDs mortality)?

Study design:
This review article included 5 prospective cohort studies with a follow-up period of 4.3-16.5 years. There were 38,449 deaths from all-cause, 4,470 from cancer and 2,841 from cardiovascular diseases among 226,297 individuals.

Results and conclusions:
The investigators found dietary total antioxidant capacity significantly reduced all-cause mortality with 38% [combined effect size = 0.62, 95% CI = 0.60-0.64].
Significant because combined effect size of 1 was not found in the 95% CI of 0.60 to 0.64. Combined effect size of 1 means no risk/association.

The investigators found dietary total antioxidant capacity significantly reduced cancer mortality with 19% [combined effect size = 0.81, 95% CI = 0.75-0.88].
Significant means that there is an association with a 95% confidence.

The investigators found dietary total antioxidant capacity significantly reduced cardiovascular diseases mortality with 29% [combined effect size = 0.71, 95% CI = 0.63-0.82].

The investigators found findings from linear dose-response meta-analysis revealed that a 5 mmol/day increment in dietary total antioxidant capacity based on ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) was associated with 7% and 15% lower risk of all-cause mortality, respectively.

The investigators found findings from non-linear dose-response meta-analysis showed a significant reduction in risk of all-cause mortality when increasing ferric reducing antioxidant power (FRAP) from 2 to 12 mmol/day [p-nonlinearity = 0.002] and oxygen radical absorbance capacity (ORAC) from 5 to 11 mmol/day [p-nonlinearity  0.001].

The investigators concluded a diet with high total antioxidant capacity decreases risk of death from all-cause, cancer and cardiovascular diseases.

Original title:
Dietary total antioxidant capacity and mortality from all causes, cardiovascular disease and cancer: a systematic review and dose-response meta-analysis of prospective cohort studies by Parohan M, Anjom-Shoae J, […], Sadeghi O

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30756144

Additional information of El Mondo:
Find more information/studies on significantly/review article, antioxidant and cancer and cardiovascular diseases mortality right here.

The easiest way to get enough antioxidants from food is to eat at least 200 grams of vegetables and at least 200 grams of fruit per day.

There exist different methods to measure the antioxidant capacity of foods: Oxygen Radical Absorbance Capacity (ORAC), Ferric Ion Reducing Power (FRAP) and Trolox Equivalence Antioxidant Capacity (TEAC). The most popular method is the ORAC determination, which was developed by the National Institutes of Health in Baltimore.

The USDA recommends an ORAC unit ingestion of about 3000 to 5000 units daily.

Objectives:
Is there an association between potato consumption and risk of all-cause, cancer and cardiovascular mortality in adults?

Study design:
This review article included 20  prospective cohort studies with 25,208 cases of all-cause mortality, 4,877 of cancer mortality and 2,366 of cardiovascular mortality.

There was no evidence for publication bias.

Results and conclusions:
The investigators found no significant association between potato consumption and risk of all-cause [RR = 0.90, 95% CI = 0.8 to 1.02, p = 0.096] and cancer [RR = 1.09, 95% CI = 0.96 to 1.24, p = 0.204] mortality.

The investigators found, in addition, no significant linear association between each 100 g/d increments in potato consumption and risk of all-cause [p = 0.7] and cancer [p = 0.09] mortality.
Moreover, nonlinear association between potato consumption and risk of cancer mortality was non-significant [p-nonlinearity = 0.99].

The investigators found, in addition, 2 of 3 studies which examined the association of potato consumption with cardiovascular mortality did not find any significant relationship.

The investigators concluded there is no association between potato consumption and risk of all-cause, cancer and cardiovascular mortality in adults.

Original title:
Potato consumption and risk of all cause, cancer and cardiovascular mortality: a systematic review and dose-response meta-analysis of prospective cohort studies by Darooghegi Mofrad M, Milajerdi A, […], Azadbakht L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30638040

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Find more information/studies on of potato consumption and elderly right here.
 

Objectives:
Existing studies suggest that dietary vitamins and carotenoids might be associated with a reduced risk of age-related cataract (ARC), although a quantitative summary of these associations is lacking. Therefore, this review article has been conducted.

Do vitamins and carotenoids intake reduce risk of the eye disease age-related cataract? 

Study design:
This review article included 8 RCTs and 12 cohort studies.

Results and conclusions:
The investigators found in cohort studies a significantly reduced risk of 19% [RR = 0.81, 95% CI = 0.71 to 0.92, p = 0.001] of age-related cataract for dietary vitamin A intake.

The investigators found in cohort studies a significantly reduced risk of 20% [RR = 0.80, 95% CI = 0.72 to 0.88, p 0.001] of age-related cataract for dietary vitamin C intake.

The investigators found in cohort studies a significantly reduced risk of 10% [RR = 0.90, 95% CI = 0.80 to 1.00, p 0.049] of age-related cataract for dietary vitamin E intake.

The investigators found in cohort studies a significantly reduced risk of 10% [RR = 0.90, 95% CI = 0.83 to 0.99, p = 0.023] of age-related cataract for dietary β-carotene intake.

The investigators found in cohort studies a significantly reduced risk of 19% [RR = 0.81, 95% CI = 0.75 to 0.89, p 0.001] of age-related cataract for dietary β lutein or zeaxanthin intake.

The investigators found in RCTs compared with the placebo, a non-significantly reduced risk of 3% [RR = 0.97, 95% CI = 0.91 to 1.03, p 0.262] of age-related cataract for vitamin E supplementation.
Non-significantly because RR of 1 was found in the 95% CI of 0.91 to 1.03. RR of 1 means no risk/association.

The investigators found in RCTs compared with the placebo, a non-significantly reduced risk of 1% [RR = 0.99, 95% CI = 0.92 to 1.07, p 0.820] of age-related cataract for β-carotene supplementation.

The investigators found in dose-response analysis of cohort studies a significantly reduced risk of 26% [RR = 0.74, 95% CI = 0.67 to 0.80, p 0.001] of age-related cataract for every 10-mg/d increase in dietary lutein or zeaxanthin intake.

The investigators found in dose-response analysis of cohort studies a significantly reduced risk of 18% [RR = 0.82, 95% CI = 0.74 to 0.91, p 0.001] of age-related cataract for every 500-mg/d increase in dietary vitamin C intake.

The investigators found in dose-response analysis of cohort studies a significantly reduced risk of 8% [RR = 0.92, 95% CI = 0.88 to 0.96, p 0.001] of age-related cataract for every 5-mg/d increase in dietary β-carotene intake.

The investigators found in dose-response analysis of cohort studies a significantly reduced risk of 6% [RR = 0.94, 95% CI = 0.90 to 0.98, p 0.001] of age-related cataract for every 5 mg/d increase in dietary vitamin A intake.

The investigators concluded dietary intake of vitamin A (at least 5 mg per day), vitamin C (at least 500 mg per day), vitamin E, β-carotene (at least 5 mg per day) and lutein or zeaxanthin intake (at least 10 mg per day) reduce risk of age-related cataract.

Original title:
Dietary vitamin and carotenoid intake and risk of age-related cataract by Jiang H, Yin Y, […], Ma L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30624584

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Find more information/studies on of vitamin A, vitamin C, vitamin E, β-carotene and elderly right here.