Nutritional advice

Objectives:
Type 1 diabetes mellitus (T1DM) causes the irreversible destruction of pancreatic beta cells. The Bacillus Calmette-Guerin (BCG) vaccine can modulate the immune response and decelerate disease progression. Therefore, this review article has been conducted.

Do patients with type 1 diabetes mellitus benefit from the Bacillus Calmette-Guerin (BCG) vaccine?

Study design:
This review article included 4 RCTs. The sample sizes ranged from 6 to 94, with a total of 198 subjects. The mean age of the examinees ranged from 10.1 to 36.0 years and the follow-up duration ranged from 1 to 8 years.

Results and conclusions:
The investigators found the pooled meta-analysis demonstrated no significant difference in HbA1c levels [MD = -0.12, 95% CI = -0.53 to 0.30, I2 = 56%] or fasting C-peptide levels [MD = -0.15, 95% CI = -0.35 to 0.06, I2 = 0%] in the BCG intervention group as compared with that in the placebo group.
The results remained unchanged after removing each study in the sensitivity analysis.

The investigators concluded there is no robust evidence to support the use of the Bacillus Calmette-Guerin (BCG) vaccine for the treatment of type 1 diabetes mellitus although the HbA1c levels tend to improve. Additional RCTs to assess the long-term effects of the Bacillus Calmette-Guerin (BCG) vaccine on glycemic control are warranted.

Original title:
Therapeutic Effects of BCG Vaccination on Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Chang YC, Lin CJ, […], Hsu HY.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7139880/

Additional information of El Mondo:
Find more information/studies on vaccination, diabetes mellitus and malnutrition right here.

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

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

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

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

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

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

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

Additional information of El Mondo:
Find more information/studies on EPA and DHA consumption and elderly right here.
EPA and DHA are present in fish.
 

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

Study design:
This review article included 10 RCTs.

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

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

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

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

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

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

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

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

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

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

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

Additional information of El Mondo:
Find more information/studies on dairy products consumption, calcium and vitamin D right here.

Objectives:
Does fish consumption reduce risk of coronary heart disease (CHD), stroke and all-cause mortality in patients with type 2 diabetes (T2D)?

Study design:
This review article included 9 prospective cohort studies with 57,394 diabetic patients.

Results and conclusions:
The investigators found for the highest compared with the lowest category of fish consumption, a significantly reduced risk of 14% [relative risk = 0.86, 95% CI = 0.76 to 0.96, I2 = 50%, n = 8] for all-cause mortality in patients with type 2 diabetes.

The investigators found for the highest compared with the lowest category of fish consumption, a significantly reduced risk of 39% [relative risk = 0.61, 95% CI = 0.29 to 0.93, I2 = 68%, n = 3] for coronary heart disease in patients with type 2 diabetes.

The investigators found there was a monotonic inverse association, with a nadir at fish consumption of approximately 2-3 servings/week, in both analyses.

The investigators concluded 2-3 servings/week of fish consumption reduce risk of all-cause mortality and coronary heart disease in patients with type 2 diabetes.

Original title:
Fish consumption and the risk of cardiovascular disease and mortality in patients with type 2 diabetes: a dose-response meta-analysis of prospective cohort studies by Jayedi A, Soltani S, […], Shab-Bidar S.

Link:
https://pubmed.ncbi.nlm.nih.gov/32410513/

Additional information of El Mondo:
Find more information/studies on fish consumption, cardiovascular disease and diabetes right here.
 

Objectives:
Does niacin (vitamin B3) supplementation improve lipid profiles and glycemic control in patients with type 2 diabetes mellitus?

Study design:
This review article included 8 RCTs comprised a total of 2,110 patients with type 2 diabetes mellitus.
Studies published ranged from 1990 to 2016 and 15 to 1,053 patients were included in each individual trial.

The follow-up duration ranged from 8.0 weeks to 12.0 months.

The study quality was assessed using the Jadad scale. 4 studies had 3 scores and the remaining 4 studies had 2 scores.

There was no significant publication bias.

Results and conclusions:
The investigators found patients’ niacin supplementation was associated with lower levels of total cholesterol [WMD = -0.28, 95% CI = -0.44 to -0.12, p =  0.001], triglyceride [WMD = -0.37, 95% CI = -0.52 to -0.21, p   0 .001] and low-density lipoprotein cholesterol (bad cholesterol) [WMD = -0.42, 95% CI = -0.50 to -0.34, p    0.001].

The investigators found, moreover, the level of high-density lipoprotein cholesterol (good cholesterol) was significantly increased when niacin supplementation [WMD = 0.33, 95% CI = 0.21 to 0.44, p 0 .001] was provided.

The investigators found, however, niacin supplementation produced no significant effects on plasma glucose [WMD = 0.18, 95% CI = -0.14 to 0.50, p = 0 .275] and hemoglobin A1c (HbA1c) levels [WMD = 0.39, 95% CI = -0.15 to 0.94, p = 0 .158].

The investigators concluded that niacin (vitamin B3) supplementation improves lipid profiles, including total cholesterol, LDL and HDL cholesterol without affecting the glycemic levels for patients with type 2 diabetes mellitus. Additional large-scale RCTs should be conducted to evaluate the long-term effectiveness of niacin supplementation.

Original title:
Effectiveness of niacin supplementation for patients with type 2 diabetes: A meta-analysis of randomized controlled trials by Xiang D, Zhang Q and Wang YT.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7373507/

Additional information of El Mondo:
Find more information/studies on cholesterol, vitamin B3 and diabetes right here.
 

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

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

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

Isoflavone interventions were generally safe and well tolerated.

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

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

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

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

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

Objectives:
Type 2 diabetes mellitus is a chronic disease that occurs among the general population. The insulin-lowering and homeostasis model assessment of insulin resistance-improving effects of inulin are unconfirmed. Therefore, this review article has been conducted.

Do inulin supplements improve HOMA-IR, fasting plasma glucose and HbA1c in patients with type 2 diabetes mellitus?

Study design:
This review article included 9 RCTs with a total of 661 participants.

The duration of the interventions ranged from 6 weeks to 12 weeks and the dosage of inulin supplementation ranged from 8.4 g to 10 g per day.

Results and conclusions:
The investigators found inulin supplementation significantly improved fasting plasma glucose [SMD = -0.55, 95% CI = -0.73 to -0.36, p = 0.0], HOMA-IR [SMD = -0.81, 95% CI = -1.59 to -0.03, p = 0.042] and HbA1c [SMD = -0.69, 95% CI = -0.92 to -0.46, p = 0.0] in patients with type 2 diabetes mellitus.

The investigators found, further subgroup analyses revealed a significant role of inulin supplementation for treatment durations ≥8 weeks [p = 0.038 for insulin, p = 0.002 for HOMA-IR, p = 0.032 for fasting plasma glucose, p = 0 for HbA1c] in patients with type 2 diabetes mellitus.

The investigators concluded that daily 8.4-10 grams of inulin supplements for at least 8 weeks improve HOMA-IR, fasting plasma glucose and HbA1c in patients with type 2 diabetes mellitus.

Original title:
Efficacy of inulin supplementation in improving insulin control, HbA1c and HOMA-IR in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials by Zhang W, Tang Y, […], Hu H.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7263925/

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

Inulin is a type of fiber that's found in certain plant foods. Chicory root is the main source of inulin in supplement form.

Objectives:
Antioxidant status is considered as important factor in the pathogenesis (the manner of development of a disease) of vitiligo. However, there are controversial findings about serum status of antioxidants in vitiligo patients. Therefore, this review article has been conducted.

Is there a relationship between serum antioxidant level (e.g. vitamin C, E, zinc and selenium) and risk of vitiligo?

Study design:
This review article included 11 studies including 570 vitiligo cases and 580 controls (people without vitiligo).

Serum vitamin A and copper level in vitiligo patients were only evaluated in single studies and not included in meta-analysis.

Results and conclusions:
The investigators found based on fixed effect model, there were no statistical difference between two groups regarding serum vitamin C levels [OR = 1.17, 95% CI = 0.74 to 1.84, p = 0.495] and serum vitamin E levels [OR = 0.61, 95% CI = 0.30 to 1.25, p = 0.180].

The investigators found in sensitivity analysis, higher serum zinc levels significantly decreased risk of vitiligo with 71% [OR = 0.29, 95% CI = 0.15 to 0.54, p 0.001].

The investigators found in sensitivity analysis, higher serum selenium level significantly increased risk of vitiligo with 331% [OR = 4.31, 95% CI = 2.72 to 6.81, p 0.001].

The investigators concluded that higher serum selenium and lower zinc level increase risk of vitiligo. Potential mechanism associated with preventive effects of zinc and the depigmentation effect of selenium should be more elucidated in further studies.

Original title:
Serum Level of Antioxidant Vitamins and Minerals in Patients With Vitiligo, a Systematic Review and Meta-Analysis by Huo J, Liu T, [...], Wang R.

Link:
https://pubmed.ncbi.nlm.nih.gov/32593085/

Additional information of El Mondo:
Find here more information/studies about antioxidants, selenium and zinc.

Vitiligo is a long-term condition where pale white patches develop on the skin. It's caused by the lack of melanin, which is the pigment in skin. Vitiligo can affect any area of skin, but it commonly happens on the face, neck and hands and in skin creases.

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

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

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

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

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

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

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

Objectives:
Does barberry (Berberis vulgaris L.) supplementation improve glycemic markers including fasting blood sugar (FBS) concentrations, insulin levels, homeostatic model assessment for insulin resistance (HOMA-IR) and glycosylated hemoglobin (HbA1c) percentage?

Study design:
This review article included 7 RCTs, comprising 452 participants.

Results and conclusions:
The investigators found the meta-analysis revealed that barberry supplementation significantly reduced insulin levels [Hedges’s = -0.67, 95% CI = -1.31 to -0.03, p = 0.04, I2 = 73.3%].
However, no significant positive effect was observed for fasting blood sugar levels [WMD = -8.06 mg/dL, 95% CI = -20.46 to 4.33, p = 0.23, I2 = 96.1%], HbA1c percentage [WMD = -0.83%, 95% CI = -2.33 to 0.67, p = 0.27, I2 = 88.3%] and HOMA-IR index [WMD = -0.55, 95% CI = -1.60 to 0.50, p = 0.30, I2 = 99.4%].

The investigators concluded barberry supplementation improves insulin levels.

Original title:
The Effect of Barberry (Berberis Vulgaris L.) on Glycemic Indices: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Safari Z, Farrokhzad A, […], Askari G.

Link:
https://www.sciencedirect.com/science/article/abs/pii/S0965229920302235?via%3Dihub

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

Objectives:
A low insulin-like growth factor 1 (IGF-1) level is known to be associated with many disorders. Several studies have shown that soy consumption may influence IGF-1, but the findings remain inconclusive. Therefore, this review article (meta-analysis) has been conducted.

Does soy consumption increase insulin-like growth factor 1 (IGF-1) level?

Study design:
This review article included 8 clinical trials.

Results and conclusions:
The investigators found, overall, a significant increment in plasma IGF-1 was observed following soy intervention [WMD = 13.5 ng/mL, 95% CI = 5.2 to 21.8, I2 = 97%].

The investigators found, subgroup analyses demonstrated a significantly greater increase in IGF-1, when soy was administered at a dosage of ≤40 g/day [WMD = 11.7 ng/mL, 95% CI = 10.9 to 12.6, I2 = 98%] and when the intervention duration was 12 weeks [WMD = 26.6 ng/mL, 95% CI = 9.1 to 44.1, I2 = 0.0%].

The investigators found, in addition, soy intervention resulted in a greater increase in IGF-1 among non-healthy subjects [WMD = 36 ng/mL, 95% CI = 32.7 to 39.4, I2 = 84%] than healthy subjects [WMD = 9.8 ng/mL, 95% CI = 8.9 to 10.7, I2 = 90%].

The investigators concluded ≤40 grams of soy consumption per day during 12 weeks increase the IGF-1 level.

Original title:
The Effect of Soy Intervention on Insulin-Like Growth Factor 1 Levels: A Meta-Analysis of Clinical Trials by Jiawei Zeng J, Feng Y, […], Chen X.

Link:
https://pubmed.ncbi.nlm.nih.gov/32072706/

Additional information of El Mondo:
Find more information/studies on subgroup analysis/significant and soja consumption right here.

Objectives:
Does high magnesium dietary intake reduce risk of type 2 diabetes and stroke?

Study design:
This review article included 53 prospective cohort studies with a total of 1,912,634 participants and 76,678 cases (persons with type 2 diabetes or stroke).

Participants were predominately middle aged at baseline (at the beginning of the studies), with a mean magnesium intake of 370 mg/day for the highest category and 232 mg/day for the lowest category.

The mean duration of all eligible studies was 10.7 years.

Results and conclusions:
The investigators found, when comparing the highest category of magnesium dietary intake (370 mg/day) to the lowest (232 mg/day), a significantly reduced risk of 22% [RR = 0.78, 95% CI = 0.75 to 0.81, p 0.001, I2 = 35.6%, p = 0.021] for type 2 diabetes.

The investigators found, when comparing the highest category of magnesium dietary intake (370 mg/day) to the lowest (232 mg/day), a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.83 to 0.94, p 0.001, I2 = 0%, p = 0.529] for total stroke.

The investigators found, when comparing the highest category of magnesium dietary intake (370 mg/day) to the lowest (232 mg/day), a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.81 to 0.95, p = 0.001, I2 = 16.9%, p = 0.265] for ischaemic stroke.

The investigators found in studies adjusted for cereal fiber dietary intake, a significantly reduced risk of 21% [RR = 0.79, 95% CI = 0.73 to 0.85, p 0.001] for type 2 diabetes.

The investigators found in studies adjusted for calcium dietary intake, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.80 to 0.99, p = 0.040] for total stroke.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 9% [RR = 0.91, 95% CI = 0.83 to 0.99] for total stroke among female.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.79 to 1.00] for ischaemic stroke among female.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.82 to 0.96] for total stroke among individuals with BMI ≥25 kg/m².

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.81 to 0.96] for ischaemic stroke among individuals with BMI ≥25 kg/m².

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 11% [RR = 0.89, 95% CI = 0.83 to 0.95] for total stroke among studies wtith ≥12-year follow-up.

The investigators found in stratified analyses by characteristics of the population and study design, a significantly reduced risk of 12% [RR = 0.88, 95% CI = 0.81 to 0.95] for ischaemic stroke among studies wtith ≥12-year follow-up.

The investigators found for every 100 mg/day increment of magnesium dietary intake, a significantly reduced risk of 6% [RR = 0.94, 95% CI = 0.93 to 0.95] for type 2 diabetes.

The investigators found for every 100 mg/day increment of magnesium dietary intake, a significantly reduced risk of 2% [RR = 0.98, 95% CI = 0.97 to 0.99] for total stroke.

The investigators found for every 100 mg/day increment of magnesium dietary intake, a significantly reduced risk of 2% [RR = 0.98, 95% CI = 0.97 to 0.99] for ischaemic stroke.

The investigators concluded magnesium dietary intake has a substantial inverse association with type 2 diabetes and (total/ ischaemic) stroke. Furthermore, female, participants with obesity (BMI ≥ 25 kg/m²) and with a longer follow-up period (≥12 years) obtain greater benefit from magnesium intake with a lower risk of total and ischaemic stroke incidence. Overall, these findings support the guidelines to address the role of magnesium dietary intake in early prevention strategies to combat type 2 diabetes and stroke. However, additional RCTs are needed in the future to validate the causality.

Original title:
Association of magnesium intake with type 2 diabetes and total stroke: an updated systematic review and meta-analysis by Zhao B, Zeng L, [...], Zhang W.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7103847/

Additional information of El Mondo:
Find more information/studies magnesium consumption, stroke and diabetes right here.

Objectives:
Is there an association between total meat, red meat, processed meat, poultry and fish intake and risk of type 2 diabetes (T2D)?

Study design:
This review article included 28 prospective cohort studies.

Results and conclusions:
The investigators found when compared with the lowest category, the highest category of total meat intake, significantly increased risk of type 2 diabetes with 33% [summary relative risk = 1.33, 95% CI = 1.16 to 1.52].
Significantly means that there is an association with a 95% confidence.

The investigators found when compared with the lowest category, the highest category of red meat intake, significantly increased risk of type 2 diabetes with 22% [summary relative risk = 1.22, 95% CI = 1.16 to 1.28].
Significantly because summary relative risk of 1 was not found in the 95% CI of 1.16 to 1.28. Summary relative risk of 1 means no risk/association.

The investigators found when compared with the lowest category, the highest category of processed meat intake, significantly increased risk of type 2 diabetes with 25% [summary relative risk = 1.25, 95% CI = 1.13 to 1.37].
Significantly means it can be said with a 95% confidence that the highest category of processed meat intake really increased risk of type 2 diabetes with 25%.

The investigators found no association between highest category of poultry intake and risk of type 2 diabetes [summary relative risk = 1.00, 95% CI = 0.93 to 1.07].
No association because summary relative risk of 1 was found in the 95% CI of 0.93 to 1.07. Summary relative risk of 1 means no risk/association.

The investigators found no association between highest category of fish intake and risk of type 2 diabetes [summary relative risk = 1.01, 95% CI = 0.93 to 1.10].

The investigators found in the dose-response analysis, each additional 100g/day of total and red meat and 50g/day of processed meat, were found to be associated with a 36% [95% CI = 1.23 to 1.49], 31% [95% CI = 1.19 to 1.45] and 46% [95% CI = 1.26 to 1.69] increased risk of type 2 diabetes, respectively.

The investigators found, in addition, there was evidence of a non-linear dose-response association between processed meat and type 2 diabetes [p = 0.004], with the risk increasing by 30% with increasing intakes up to 30g/day.

The investigators concluded 100g/day of total meat, 100g/day red meat and 50g/day of processed meat, increase risk of type 2 diabetes.

Original title:
Meat and fish intake and type 2 diabetes: dose-response meta-analysis of prospective cohort studies by Yang X, Li Y, […], Li L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32302686

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Objectives:
Is there a causal relationship between psyllium (a dietary fiber) consumption and improvements of risk factors of diabetes?

Study design:
This review article included 9 RCTs with 395 participants.

Results and conclusions:
The investigators found psyllium consumption significantly reduced triglycerides levels with 19.18 mg/dL [WMD = -19.18 mg/dL, 95% CI = -31.76 to -6.60, I2 = 98%].

The investigators found psyllium consumption significantly reduced low-density lipoprotein cholesterol levels with 8.96 mg/dL [WMD = -8.96 mg/dL, 95% CI = -13.39 to -4.52, I2 = 97%].

The investigators found psyllium consumption significantly reduced fasting blood sugar levels with 8.96 mg/dL [WMD = -31.71 mg/dL, 95% CI = -50.04 to -13.38, I2 = 97%].

The investigators found psyllium consumption significantly reduced hemoglobin A1c levels with 0.91% [WMD = -0.91%, 95% CI = -1.31 to -0.51, I2 = 99%].

The investigators found no significant change in high-density lipoprotein, body mass index, cholesterol and weight following psyllium consumption.

The investigators concluded there is a significant reduction in triglycerides, low-density lipoprotein cholesterol (bad cholesterol), fasting blood sugar and hemoglobin A1c levels following psyllium consumption among diabetic patients.

Original title:
The effect of psyllium consumption on weight, body mass index, lipid profile, and glucose metabolism in diabetic patients: A systematic review and dose-response meta-analysis of randomized controlled trials by Xiao Z, Chen H, [...], Wei Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31919936

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

Psyllium is a form of fiber made from the husks of the Plantago ovata plant’s seeds. The psyllium husk is a naturally occurring source of soluble fiber.
Psyllium is commonly found in cereals, dietary supplements and is also added to some foods including baked products such as breads, cereal bars and rice/grain cakes.
 

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

Does statin use decrease Alzheimer disease?

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

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

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

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

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

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

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

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

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

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

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

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

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

Does a high carbohydrate intake increase risk of fracture?

Study design:
This review article included observational studies.

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

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

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

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

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

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

Objectives:
Previous findings on the associations of legume and soy intake with the risk of type 2 diabetes are conflicting. Therefore, this review article (meta-analysis) has been conducted.

Does legume or soy dietary intake reduce risk of type 2 diabetes?

Study design:
This review article included 15 unique cohort studies with a total of 565,810 individuals and 32,093 incident cases (persons with type 2 diabetes).

Overall quality of evidence was rated as moderate for total legumes and low for total soy and soy subtypes.

Results and conclusions:
The investigators found no association between total legumes dietary intake and risk of type 2 diabetes [summary RR = 0.95, 95% CI = 0.79 to 1.14, I2 = 84.8%].
No association because RR of 1 was found in the 95% CI of 0.79 to 1.14. RR of 1 means no risk/association.

The investigators found no association between total soy dietary intake and risk of type 2 diabetes [summary RR = 0.83, 95% CI = 0.68 to 1.01, I2 = 90.8%].

The investigators found no association between soy milk dietary intake and risk of type 2 diabetes [summary RR = 0.89, 95% CI = 0.71 to 1.11, I2 = 91.7%].

The investigators found tofu dietary intake significantly reduced risk of type 2 diabetes with 8% [summary RR = 0.92, 95% CI = 0.84 to 0.99].
Significantly because RR of 1 was not found in the 95% CI of 0.84 to 0.99. RR of 1 means no risk/association.

The investigators found soy protein dietary intake significantly reduced risk of type 2 diabetes with 16% [summary RR = 0.84, 95% CI = 0.75 to 0.95].

The investigators found soy isoflavones dietary intake significantly reduced risk of type 2 diabetes with 12% [summary RR = 0.88, 95% CI = 0.81 to 0.96].

The investigators found in dose-response analysis, significant linear inverse associations for tofu, soy protein and soy isoflavones [all p 0.05].

The investigators concluded dietary intakes of tofu, soy protein and soy isoflavones reduce incident type 2 diabetes. These findings support recommendations to increase intakes of certain soy products for the prevention of type 2 diabetes. However, the overall quality of evidence was low and more high-quality evidence from prospective studies is needed.

Original title:
Legume and soy intake and risk of type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies by Tang J, Wan Y, […], Feng F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31915830

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

Objectives:
Which factors increase risk of dementia?

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

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

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

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

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

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

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

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

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

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

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

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

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