Nutrition and health

Objectives:
Previous meta-analysis studies have indicated inverse associations between some carotenoids and risks of metabolic syndrome, cardiovascular disease, cancer and all-cause mortality. However, the results for associations between carotenoids and type 2 diabetes (T2D) remain inconsistent and no systematic assessment has been done on this topic. Therefore, this review article (meta-analysis) has been conducted.

Do higher dietary intakes and circulating concentrations of carotenoids reduce risk of type 2 diabetes?

Study design:
This review article included 13 studies.

Results and conclusions:
The investigators found for the the highest versus the lowest categories of dietary intake of β-carotene a significantly reduced risk of 22% for type 2 diabetes [pooled RR = 0.78, 95% CI = 0.70 to 0.87, I2 = 13.7%, n = 6].
This significantly reduced risk was also found for total carotenoids (n = 2), α-carotene (n = 4), and lutein/zeaxanthin (n = 4), with pooled RRs ranging from 0.80 to 0.91, whereas no significant associations were observed for β-cryptoxanthin and lycopene.

The investigators found for the the highest versus the lowest categories of circulating concentration of β-carotene a significantly reduced risk of 40% for type 2 diabetes [pooled RR = 0.60, 95% CI = 0.46 to 0.78, I2 = 56.2%, n = 7].
This significantly reduced risk was also found for total carotenoids (n = 3), lycopene (n = 4), and lutein (n = 2), with pooled RRs ranging from 0.63 to 0.85, whereas no significant association was found for circulating concentrations of α-carotene and zeaxanthin when comparing extreme categories.

The investigators found dose-response analysis indicated that nonlinear relations were observed for circulating concentrations of α-carotene, β-carotene, lutein and total carotenoids [all p-nonlinearity 0.05], but not for other carotenoids or dietary exposures.

The investigators concluded that higher dietary intakes and circulating concentrations of total carotenoids, especially β-carotene, are associated with a lower risk of type 2 diabetes. More studies are needed to confirm the causality and explore the role of foods rich in carotenoids in prevention of type 2 diabetes.

Original title:
Dietary Intake and Circulating Concentrations of Carotenoids and Risk of Type 2 Diabetes: A Dose-Response Meta-Analysis of Prospective Observational Studies by Jiang YW, Sun ZH, [...], Pan A.

Link:
https://pubmed.ncbi.nlm.nih.gov/33979433/

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Objectives:
Although current guidelines recommend reduction of salt intake in patients with diabetes, the benefits of reducing salt intake in people with type 2 diabetes mellitus (T2DM) lack clear evidence. Therefore, this review articles has been conducted.

Does dietary sodium restriction causally reduce blood pressure in patients with type 2 diabetes mellitus (T2DM)?

Study design:
This review article included 8 RCTs with 10 trials (7 cross-over and 3 parallel designs).
No publication bias was found from Begg's and Egger's tests.

Results and conclusions:
The investigators found compared with ordinary sodium intake, dietary sodium restriction significantly decreased 24-hour urine sodium level [WMD = -38.430 mmol/24h, 95% CI = -41.665 mmol/24h to -35.194 mmol/24h].

The investigators found dietary sodium restriction significantly lowered systolic blood pressure [WMD = -5.574 mm Hg, 95% CI = -8.314 to -2.834 mm Hg, I2 = 0.0%] and diastolic blood pressure [WMD = -1.675 mm Hg, 95% CI = -3.199 to -0.150 mm Hg, I2 = 0.0%].

The investigators concluded that dietary sodium restriction causally reduces systolic blood pressure and diastolic blood pressure in patients with type 2 diabetes mellitus (T2DM).

Original title:
Effect of dietary sodium restriction on blood pressure in type 2 diabetes: A meta-analysis of randomized controlled trials by Ren Y, Liqiang Qin L, […], Ma Y.

Link:
https://pubmed.ncbi.nlm.nih.gov/33838996/

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Salt consists of sodium and chloride. So a dietary sodium restriction means a reduction in dietary salt intake.

A diet with dietary salt restriction is a diet with maximum 0.2 grams of salt per 100 kcal.

The easiest way to follow this diet is to choose only products/meals with maximum 0.2 grams of salt per 100 kcal. These products from the supermarket contain maximum 0.2 grams of salt per 100 kcal.

However, the most practical way to follow this diet is, all your daily consumed products/meals should contain on average maximum 0.2 grams of salt per 100 kcal.
To do this, use the 7-points nutritional profile app to see if your daily diet contains maximum 0.2 grams of salt per 100 kcal.

Objectives:
Evidence regarding associations between potato consumption and type 2 diabetes (T2D) and gestational diabetes mellitus (GDM) risks is accumulating. Therefore, this review article has been conducted.

Does a high potato intake increase type 2 diabetes and gestational diabetes mellitus (diabetes mellitus during pregnancy) risk?

Study design:
This review article included 19 studies (13 for type 2 diabetes and 6 for gestational diabetes mellitus) with a total of 21,357 type 2 diabetes cases among 323,475 participants and 1,516 gestational diabetes mellitus cases among 29,288 pregnancies.

Results and conclusions:
The investigators found meta-analysis showed a significantly increased risk of 19% [RR = 1.19, 95% CI = 1.06 to 1.34] for type 2 diabetes for total potato intakes among Western populations.

The investigators found meta-analysis showed a significantly increased risk of 8% [RR = 1.08, 95% CI = 1.00 to 1.16] for type 2 diabetes for baked/boiled/mashed potato intakes among Western populations.

The investigators found meta-analysis showed a significantly increased risk of 33% [RR = 1.33, 95% CI = 1.03 to 1.70] for type 2 diabetes for French fries/fried potato intakes among Western populations.

The investigators found dose-response meta-analysis demonstrated a significantly increased type 2 diabetes risk by 10% [95% CI = 1.07 to 1.14, p for trend 0.001], 2% [95% CI = 1.00 to 1.04, p for trend = 0.02] and 34% [95% CI = 1.24 to 1.46, p for trend 0.001] among Western populations for each 80 g/day (serving) increment in total potato, unfried potato and fried potato intakes, respectively.

The investigators found dose-response meta-analysis demonstrated a significantly increased gestational diabetes mellitus risk by 22% [95% CI = 1.06 to 1.42, p for trend 0.007] among Western populations for each 80 g/day (serving) increment in total potato intakes.

The investigators found dose-response meta-analysis demonstrated a significantly increased gestational diabetes mellitus risk by 26% [95% CI = 1.07 to 1.48, p for trend = 0.006] among Western populations for each 80 g/day (serving) increment in unfried potato intakes.

The investigators concluded that higher potato intake (at least 80g per day) is associated with higher type 2 diabetes risk among Western populations. The positive relationship presents a significant dose-response manner. Wisely controlled potato consumption may confer potential glucometabolic benefits.

Original title:
Dietary potato intake and risks of type 2 diabetes and gestational diabetes mellitus by Guo F, Zhang Q, [...], Ma L.

Link:
https://pubmed.ncbi.nlm.nih.gov/34130021/

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Objectives:
Does vitamin C supplementation improve triglyceride and cholesterol levels in patients with type 2 diabetes mellitus?

Study design:
This review article included 15 studies with 872 participants.

Results and conclusions:
The investigators found, findings from 15 studies indicated that vitamin C supplementation significantly decreased triglyceride (TG) levels [WMD= -16.48 mg/dL, 95% CI = -31.89 to -1.08, p 0.001] and total cholesterol (TC) levels [WMD = -13.00 mg/dL, 95% CI = -23.10 to -2.91, p 0.001] in patients with type 2 diabetes mellitus.

The investigators found, however, vitamin C supplementation failed to improve LDL (bad cholesterol) and HDL cholesterol (good cholesterol) levels. 

The investigators found the meta-regression analysis suggested that lipid profile improvement was affected by duration of vitamin C treatment.

The investigators found dose-response analysis showed that vitamin C supplementation changed LDL cholesterol significantly based on vitamin C dose.

The investigators concluded that vitamin C supplementation improves lipid profile via decreases in triglyceride and total cholesterol levels in patients with type 2 diabetes mellitus. It appears that vitamin C supplementation is more beneficial to lipid profile in long-term vs. short term interventions.

Original title:
Does vitamin C supplementation exert profitable effects on serum lipid profile in patients with type 2 diabetes? A systematic review and dose-response meta-analysis by Namkhah Z, Ashtary-Larky D, […], Asbaghi O.

Link:
https://pubmed.ncbi.nlm.nih.gov/33984490/

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Objectives:
Does spirulina supplementation improve glycemic related markers (like, fasting blood glucose, post prandial blood sugar and HbA1c levels) and lipid profile (like, triglyceride and cholesterol levels) among type 2 diabetes patients?

Study design:
This review article included 8 RCTs (9 arms).

Results and conclusions:
The investigators found, spirulina supplementation significantly reduced fasting blood glucose levels [-17.88 mg/dL, 95% CI = -26.99 to -8.78, I2 = 25%] among type 2 diabetes patients.

The investigators found, spirulina supplementation significantly reduced triglyceride levels [-30.99 mg/dL, 95% CI = -45.20 to -16.77, I2 = 50%] among type 2 diabetes patients.

The investigators found, spirulina supplementation significantly reduced total cholesterol levels [-18.47 mg/dL, 95% CI = -33.54 to -3.39, I2 = 73%] among type 2 diabetes patients.

The investigators found, spirulina supplementation significantly reduced LDL cholesterol (bad cholesterol) levels [-20.04 mg/dL, 95% CI = -34.06 to -6.02, I2 = 75%] among type 2 diabetes patients.

The investigators found, spirulina supplementation significantly reduced VLDL cholesterol levels [-6.96 mg/dL, 95% CI = -9.71 to -4.22, I2 = 33%] among type 2 diabetes patients.

The investigators found, spirulina supplementation significantly increased HDL cholesterol (good cholesterol) levels among type 2 diabetes patients.

The investigators found no significant effect on HbA1C or post prandial blood sugar among type 2 diabetes patients following spirulina supplementation.

The investigators concluded that spirulina supplementation has beneficial effects on fasting blood glucose and blood lipid profiles among type 2 diabetes patients.

Original title:
The effect of spirulina on type 2 diabetes: a systematic review and meta-analysis by Hatami E, Ghalishourani SS, […], Mansour-Ghanaei F.

Link:
https://pubmed.ncbi.nlm.nih.gov/34178867/

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Objectives:
Does grapes/grape products supplementation improve glycemic indices (like HOMA-IR, Hb1Ac and fasting insulin level) in adults or in other words, does eating grapes or grape products causally improve glycemic indices in adults?

Study design:
This review article included 29 RCTs with a total of 1,297 participants.

Results and conclusions:
The investigators found, overall, the grapes/grape products supplementation significantly reduced homeostatic model assessment of insulin resistance (HOMA-IR) [WMD = -0.54, 95% CI = -0.91 to -0.17, p = 0.004] in adults.   
Significantly because the calculated p-value of = 0.004 was less than the p-value of 0.05.

The investigators found, however, the grapes/grape products supplementation did not affect fasting insulin levels [WMD = -0.90 μIU/mL, 95% CI = -1.04 to 2.84, p = 0.362] and hemoglobin A1c (Hb1Ac) percentage [WMD = 0.00%, 95% CI = -0.10 to 0.11, p = 0.916] in the main analyses.
Did not affect because the calculated p-value of 0.916 was larger than the p-value of 0.05.

The investigators concluded that the grapes/grape products supplementation reduces homeostatic model assessment of insulin resistance (HOMA-IR) in adults. Further, large-scale RCTs with longer duration are required to confirm these results.

Original title:
The effect of grapes/grape products on glycemic response: A systematic review and meta-analysis of randomized controlled trials by Moodi V, Abedi S, […], Miraghajani M.

Link:
https://pubmed.ncbi.nlm.nih.gov/33893683/

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Homeostatic model assessment of insulin resistance (HOMA-IR) is a method for assessing β-cell function and insulin resistance (IR) from basal (fasting) glucose and insulin or C-peptide concentrations. HOMA-IR is an indicator of insulin resistance in diabetic patients. The higher the value, the more resistant you are to insulin. Diabetic patients often have a high HOMA-IR value.

Objectives:
Does chromium supplementation improve lipid profile (serum levels of triglyceride and cholesterol) in patients with type 2 diabetes mellitus (T2DM)?

Study design:
This review article included  24 RCTs (with 28 effect sizes).

Results and conclusions:
The investigators found that chromium supplementation resulted in a significant decrease in serum levels of triglyceride (TG) in patients with type 2 diabetes mellitus [MD = -6.54 mg/dL, 95 % CI = -13.08 to -0.00, p = 0.050].
Significant means that there is an association with a 95% confidence.

The investigators found that chromium supplementation resulted in a significant decrease in serum levels of total cholesterol (TC) in patients with type 2 diabetes mellitus [WMD = -7.77 mg/dL, 95 % CI = -11.35 to -4.18, p 0.001].

The investigators found that chromium supplementation significantly increased high-density lipoprotein cholesterol (HDL cholesterol or good cholesterol) in patients with type 2 diabetes mellitus [WMD = 2.23 mg/dL, 95 % CI = 0.07 to 4.40, p = 0.043] level.

The investigators found, however, chromium supplementation did not have significant effects on low-density lipoprotein cholesterol (LDL cholesterol or bad cholesterol) in patients with type 2 diabetes mellitus [WMD = -8.54 mg/dL, 95 % CI = -19.58 to 2.49, p = 0.129] level.

The investigators concluded that chromium supplementation decreases serum levels of triglyceride (TG) and total cholesterol (TC) and increases HDL cholesterol (good cholesterol) levels in patients with type 2 diabetes mellitus. It should be noted that the lipid-lowering properties of chromium supplementation are small and may not reach clinical importance.

Original title:
Effects of chromium supplementation on lipid profile in patients with type 2 diabetes: A systematic review and dose-response meta-analysis of randomized controlled trials by Asbaghi O, Naeini F, […], Naeini AA.

Link:
https://pubmed.ncbi.nlm.nih.gov/33813266/

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Objectives:
Does L-arginine supplementation improve biomarkers (fasting blood sugar, insulin, HbA1c and HOMA-IR values) of glycemic control in adults?

Study design:
This review article included 12 randomised clinical trials (RCTs).

Results and conclusions:
The investigators found L-arginine supplementation had no significant effect on serum fasting blood sugar (FBS) [weighted mean difference (WMD) = -3.38 mg/dL, 95% CI = -6.79 to 0.04, p = 0.53], serum insulin [WMD = -0.12 Hedges' g, 95% CI = -0.33 to 0.09, p = 0.27], glycated haemoglobin A1c (HbA1c) [WMD = -0.04%, 95% CI = -0.25 to 0.17, p = 0.71] and homeostasis model assessment for insulin resistance (HOMA-IR) [WMD = -0.48, 95% CI = -1.15 to 0.19, p = 0.15].
No significant because the calculated p-value of 0.15 was larger than the p-value of 0.05.

The investigators concluded although several animal studies have proposed that L-arginine supplementation might improve blood glucose control, the present review article could not confirm this benefit in humans.

Original title:
Effects of L-arginine supplementation on biomarkers of glycemic control: a systematic review and meta-analysis of randomised clinical trials by Karimi E, Hatami E, […], Askari G.

Link:
https://pubmed.ncbi.nlm.nih.gov/33426939/

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Arginine is classified as a semiessential or conditionally essential amino acid, depending on the developmental stage and health status of the individual, that helps the body build protein. L-arginine is also found in most protein-rich foods, including fish, red meat, poultry, soy, whole grains, beans and dairy products.
 

Objectives:
Does garlic supplementation reduce adiponectin and leptin serum levels?

Study design:
This review article included 5 RCTs.

Results and conclusions:
The investigators found that garlic supplementation did not significantly affect adiponectin [Hedges's = 0.20, 95% CI = -0.06 to 0.47, p = 0.12] and leptin [Hedges's = 0.08, 95% CI = -0.26 to 0.41, p = 0.65] concentrations in comparison with placebo.

The investigators found, however, in the subgroup analysis, significantly increased serum adiponectin level was seen following garlic supplementation in trials with a mean age of participants ˂30 years [Hedges's = 0.44, 95% CI = 0.01 to 0.87, p = 0.04], the doses ˂1.5 g/day [Hedges's = 0.38, 95% CI = 0.02 to 0.71, p = 0.04] and trials with duration ≥8 weeks [Hedges's = 0.48, 95% CI = 0.08 to 0.89, p = 0.02].

The investigators concluded that ˂1.5 g/day garlic supplementation during ≥8 weeks reduces adiponectin level among participants ˂30 years.

Original title:
Systematic review and meta-analysis of randomized, controlled trials on the effects of garlic supplementation on serum adiponectin and leptin levels by Shekarchizadeh-Esfahani P, Hassani B, […], Soraya N.

Link:
https://pubmed.ncbi.nlm.nih.gov/33792129/

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Adiponectin is a fat-derived hormone that appears to play a crucial role in protecting against insulin resistance/diabetes and atherosclerosis (atherosclerosis is the dominant cause of cardiovascular disease (CVD)). Decreased adiponectin levels are thought to play a central role in the development of obesity, cardiovascular disease and type 2 diabetes in humans.

Objectives:
Previous meta-analyses, with some methodological controversies, have assessed the relation between nut consumption and type 2 diabetes (T2D) risk and pointed to contradictory results. Therefore, this review article has been conducted.

Does nut consumption reduce risk of type 2 diabetes?

Study design:
This review article included 5 prospective cohort studies and 3 cross-sectional studies.
The certainty of the evidence using NutriGrade was very low for all the exposures.

Results and conclusions:
The investigators found meta-analyses of cross-sectional studies and prospective cohort studies, comparing the highest with the lowest categories, revealed a nonsignificant association between total nut consumption and type 2 diabetes.
Nonsignificant means that there is no association with a 95% confidence.

The investigators found meta-analyses of prospective cohort studies showed that peanut butter consumption significantly reduced type 2 diabetes incidence with 13% [RR = 0.87, 95% CI = 0.77 to 0.98, I2 = 50.6%, p = 0.16], whereas no association was observed between peanuts or tree nuts and type 2 diabetes.

The investigators found there was no evidence of a linear dose-response or nonlinear dose-response gradient for total nut and peanut consumption in prospective cohort studies.

The investigators concluded peanut butter consumption may reduce type 2 diabetes incidence. May reduce because the certainty of the evidence using NutriGrade was very low.

Original title:
Nut consumption and type 2 diabetes risk: a systematic review and meta-analysis of observational studies by Becerra-Tomás N, Paz-Graniel I, […], Salas-Salvadó J.

Link:
https://pubmed.ncbi.nlm.nih.gov/33471083/

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Objectives:
Peripheral neuropathy (PN) is common in patients with diseases that are in turn associated with deficiency of the B-vitamins, and vitamin treatment has shown mixed results. Therefore, this review article has been conducted.

Does a low vitamin B level increase the risk of peripheral neuropathy?

Study design:
This review article included 46 observational studies and 7 interventional studies.

Results and conclusions:
The investigators found the presence of peripheral neuropathy was significantly associated with lowered B12 levels [1.51, 95% CI = 1.23 to 1.84, n = 34, I2 = 43.3%, p = 0.003].

The investigators found the presence of peripheral neuropathy was significantly associated with elevated methylmalonic acid levels [2.53, 95% CI = 1.39 to 4.60, n = 9, I2 = 63.8%, p = 0.005].

The investigators found the presence of peripheral neuropathy was significantly associated with elevated homocysteine levels [3.48, 95% CI = 2.01 to 6.04, n = 15, I2 = 70.6%, p 0.001].

The investigators found treatment with vitamin B1 was associated with a significant improvement in symptoms of peripheral neuropathy [5.34, 95% CI = 1.87 to 15.19, n = 3, I2 = 64.6%, p = 0.059].

The investigators found B12 treatment (vs. the comparators) showed a non-significant association with symptom improvement [1.36, 95% CI = 0.66 to 2.79, n = 4, I2 = 28.9%].

The investigators found analysis of 7 trials combined showed a non-significant higher odds ratio for improvement under treatment with the B-vitamins [2.58, 95% CI = 0.98 to 6.79, I2 = 80.0%, p 0.001].

The investigators concluded peripheral neuropathy is associated with lowered plasma vitamin B12 and elevated methylmalonic acid and homocysteine levels. Well-designed studies, especially in non-diabetes peripheral neuropathy, are needed.

Original title:
Association between neuropathy and B-vitamins: A systematic review and meta-analysis by Stein J, Geisel J and Obeid R.

Link:
https://pubmed.ncbi.nlm.nih.gov/33619867/

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Peripheral neuropathy refers to the conditions that result when nerves that carry messages to and from the brain and spinal cord from and to the rest of the body are damaged or diseased.

Increased methylmalonic acid levels are a sensitive indicator of mild vitamin B12 deficiency.
 

Objectives:
Does a low-carbohydrate diet (LCD) causally increase adiponectin concentration in adults?

Study design:
This review article included 11 RCTs with 534 participants in low-carbohydrate diet group and 513 participants in control group (group without a low-carbohydrate diet).
Proportion of carbohydrate from calorie was from 4 to 34% (4-34 En%).
Time of the follow-up varied between studies and ranged from 6 to 152 weeks.
Meta-regression analysis revealed that age [β = 0.04, p = 0.15], baseline BMI [β= -0.15, p = 0.15], time of follow-up [β = 0.01, p = 0.17], energy percentage of carbohydrates [β = 0.004, p = 0.90], energy percentage of protein [β = -0.12, p = 0.08], energy percentage of fat [β = 0.20, p = 0.61] and baseline adiponectin [β = 0.001, p = 0.97] are not sources of heterogeneity

Results and conclusions:
The investigators found low-carbohydrate diet significantly increased adiponectin concentration [0.02 µg/mL, 95% CI = 0.01 to 0.03, p 0.001].

The investigators found dose-response analysis indicated a nonlinear association between the percentage of carbohydrate and change in adiponectin level from baseline [p = 0.04].

The investigators found in subgroup analysis based on the proportion of carbohydrate from calorie, there was a significant increase in adiponectin concentration in studies that prescribed 30% of calorie from carbohydrates [0.12 µg/mL, 95% CI = 0.07 to 0.18].
In contrast, diets which consisted ≥30% of carbohydrates had no significant effect on adiponectin [0.50 µg/mL, 95% CI = -0.46 to 1.48].

The investigators concluded that a diet with 30% of calorie from carbohydrates (diet with 30 En% carbohydrates) causally increases adiponectin concentration in adults.

Original title:
Effect of low-carbohydrate diet on adiponectin level in adults: a systematic review and dose-response meta-analysis of randomized controlled trials by Shemirani F, Golzarand M, […], Mahmoudi M.

Link:
https://pubmed.ncbi.nlm.nih.gov/33455438/

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The most easy way to follow a diet with maximum 30% of calorie from carbohydrates (diet with 30 En% carbohydrates) is to choose only meals/products with maximum 30 En% carbohydrates. Check here which products contain maximum 30 En% carbohydrates. However, the most practical way to follow a diet with maximum 30 En% carbohydrates is, all meals/products that you eat on a daily basis should on average contain maximum 30 En% carbohydrates.
30 En% carbohydrates means that the total amounts of carbohydrates make up for a 30% of the total kcal of the diet.

Adiponectin is a protein hormone produced and secreted exclusively by adipocytes (fat cells) that regulates the metabolism of lipids and glucose. Adiponectin influences the body's response to insulin. Adiponectin also has antiinflammatory effects on the cells lining the walls of blood vessels.
 

Objectives:
Fish oil has been shown to reduce the risk of metabolic disorders. However, the effects of fish oil intervention on glucose metabolism and insulin sensitivity are still controversial, especially in children. Therefore, this review article has been conducted.

Do fish oil supplements (EPA + DHA) improve insulin sensitivity in children?

Study design:
This review article included 13 RCTs with 567 children in placebo group (group without fish oil supplements) and 565 in fish oil group (intervention group).

No heterogeneity was found for the pooled and subgroup analyses.

Results and conclusions:
The investigators found compared with the placebo group, fish oil intervention had beneficial effects on insulin sensitivity in the pooled analysis [WMD = -0.219, 95% CI = -0.392 to -0.046, p = 0.013].

These beneficial effects were also found in subgroup analyses, when the fish oil intervention period was short-term (≤6 months) low dose (eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA) dose 1.5 g/day) and high ratio (eicosapentaenoic acid to docosahexaenoic acid ≥1).

The investigators concluded fish oil supplements, especially 1.5 g/day EPA + DHA during 6 months, improve insulin sensitivity in children.

Original title:
Effect of Fish Oil on Insulin Sensitivity in Children: A Systematic Review and Meta-Analysis of Randomized, Controlled Trials by Hou M, Zhou W, [...], Lv H.

Link:
https://pubmed.ncbi.nlm.nih.gov/33388274/

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Objectives:
Does type 1 diabetes mellitus (T1DM) decrease bone mineral density (BMD) in children and adolescents?

Study design:
This review article included 9 cross-sectional studies with a total of 1,522 children and adolescents.

Funnel plot and the Egger test did not reveal significant publication bias.

Results and conclusions:
The investigators found a significant decrease in bone mineral density Z-score in the whole body [pooled WMD = -0.47, 95% CI = -0.92 to -0.02, I2 = 80.2%] and lumbar spine [pooled WMD = -0.41, 95% CI = -0.69 to -0.12, I2 = 80.3%] in children and adolescents with type 1 diabetes mellitus, which was consistent in published studies from Asia and South America, but inconsistent in the North America and Europe.
Sensitivity analyses did not modify these findings.

The investigators found, importantly, the differences in bone mineral density Z-scores were independent of age, level of glucose control (HbA1c) and prepubertal stage.

The investigators concluded type 1 diabetes mellitus (T1DM) decreases bone mineral density (BMD) Z-scores in the whole body and lumbar spine in children and adolescents.

Original title:
Association between type 1 diabetes mellitus and reduced bone mineral density in children: a meta-analysis by Zhu Q, J Xu J, […], Shi J.

Link:
https://pubmed.ncbi.nlm.nih.gov/33404757/  

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Objectives:
Diabetes prevention is a public health priority. Vitamin D supplementation may help prevent the development of diabetes in persons at increased risk. Therefore, this review article has been conducted.

Does vitamin D supplementation reduce risk of type 2 diabetes?

Study design:
This review article included 28 RCTs with 3,848 participants.

The sample size varied from 23 to 511.
The mean age of participants ranged from 26 years to 71 years.
The duration of follow-up across studies ranged from 2 months to 5 years, with a median follow-up of 22 weeks [interquartile range (IQR): 14 to 48 weeks], a duration long enough to detect changes in measured outcomes.

The average vitamin D supplementation dose of 88 µg/d (3500 IU/d).
All included trials measured the effect of vitamin D supplementation on serum 25(OH)D concentrations.

Results and conclusions:
The investigators found overall, serum 25(OH)D concentrations in the treated arms (vitamin D-supplemented groups) significantly improved by 45.1 nmol/L [95% CI = 41.3 to 48.9, p 0.001, I2 = 97.4%].

The investigators found compared with the control group, vitamin D supplementation significantly reduced HbA1c level by -0.48% [95% CI = -0.79 to -0.18, p = 0.002, I2 = 92.1%].
However, after adjusting the effect size for potential publication bias using the “trim and fill” method, 4 potentially missing studies were imputed in the funnel plot and the effect size increased from -0.48% [95% CI = -0.79 to -0.18] to -0.71% [95% CI = -1.02 to -0.39].

The investigators found compared with the control group, vitamin D supplementation significantly reduced fasting plasma glucose level by -0.46 mmol/L [95% CI = -0.74 to -0.19, p = 0.001, I2 = 92.4%].  
However, after adjusting the effect size for potential publication bias using the “trim and fill” method, 6 potentially missing studies were imputed in the funnel plot and the effect size increased -0.46 mmol/L [95% CI = -0.74 to ­0.19] to -0.72 mmol/L [95% CI =-1.02 to -0.42].

The investigators found compared with the control group, vitamin D supplementation significantly reduced HOMA-IR level by -0.39 [95% CI = -0.68 to -0.11, p = 0.007, I2 = 91.3%].
However, after adjusting the effect size for potential publication bias using the “trim and fill” method, 5 potentially missing studies were imputed in the funnel plot and the effect size increased from -0.39 [95% CI = -0.68 to -0.11] to -0.62 [95% CI = -0.92 to -0.32].

The investigators found in subgroup analysis both HbA1c and HOMA-IR showed a greater reduction over time among overweight/obese individuals compared with prediabetics [HbA1c = -0.98 ± 0.45 vs -0.29 ± 0.14, p = 0.1 and HOMA-IR = -0.62 ± 0.23 vs -0.07 ± 0.16, p = 0.05].

The investigators found in subgroup analysis vitamin D supplementation significantly decreased HbA1c [p = 0.05], fasting plasma glucose level [p = 0.05] and HOMA-IR [p = 0.1] to a greater extent when serum 25(OH)D concentration achieved was above 86 nmol/L.

The investigators found in subgroup analysis vitamin D supplementation for less than 6 months provided a larger effect size on HbA1c in comparison with long durations [-0.75 ± 0.33 vs -0.25 ± 0.11, p = 0.1].

The investigators found in subgroup analysis HbA1c showed greater improvement in populations with a mean age younger than 45 years in comparison with older populations [-1.15 ± 0.6 vs -0.30 ± 0.1, p = 0.05].

The investigators found in subgroup analysis greater reductions were found within HbA1c and fasting plasma glucose levels when baseline (at the beginning of the study) mean serum 25(OH)D concentration was ≥50 nmol/L, whereas the lowering effect was significantly less in the subgroup with baseline mean 25(OH)D 50 nmol/L [HbA1c = -0.79 ± 0.25 vs -0.14 ± 0.13, p = 0.04 and fasting plasma glucose level = -0.69 ± 0.21 vs -0.11 ± 0.10, p = 0.05].

The investigators concluded 88 µg/d vitamin D supplementation during 22 weeks improves glycemic measures and insulin sensitivity and may be useful as part of a preventive strategy for type 2 diabetes, particularly among overweight/obese individuals younger than 45 years.

Original title:
Vitamin D Supplementation, Glycemic Control, and Insulin Resistance in Prediabetics: A Meta-Analysis by Mirhosseini N, Vatanparast H, [...], Kimball SM.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6016617/

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

HbA1c, FPG, HOMA-IR and plasma glucose after 2-hour oral glucose tolerance test (2HPG) are different parameters associated with (pre)diabetes.

 

Objectives:
High potato intake has been suggested as a risk factor for the development of type 2 diabetes. Therefore, this review article has been conducted.

Does potato intake increase risk of type 2 diabetes?

Study design:
This review article included 6 prospective cohort studies with a total of 4,545,230 person-year of follow-up and 17,758 diabetes cases.

Results and conclusions:
The investigators found for every increment of 1 serving/day of total potato consumption a significantly increased risk of 20% [HR = 1.20, 95% CI = 1.13 to 1.127, p 0.001, I2 = 27.1%, p for heterogeneity = 0.23] for type 2 diabetes both in men en women.

The investigators found for 2 servings/day of total potato consumption a significantly increased risk of 44% [HR = 1.44, 95% CI = 1.28 to 1.63] for type 2 diabetes both in men en women.

The investigators found for 3 servings/day of total potato consumption a significantly increased risk of 74% [HR = 1.74, 95% CI = 1.45 to 2.09] for type 2 diabetes both in men en women.

The investigators found significant evidence of a non-linear association between total potato consumption and risk of type 2 diabetes [X2 = 17.5, p for linearity 0.001].

The investigators concluded that long-term high consumption of potato (each serving a day increase) is strongly associated with increased risk of type 2 diabetes. These findings suggest that diet-health policy may be of importance in the prevention of diabetes.

Original title:
Potato consumption and risk of type 2 diabetes: A dose-response meta-analysis of cohort studies by Bidel Z, Teymoori F, […], Nazarzadeh M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30144898

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

According to the USDA Dietary Guidelines a serving of potato is 1 cup diced, mashed or baked or 1 medium boiled potato.

 

Objectives:
Several studies have been published about the effect of garlic on lipid profile and blood glucose in diabetic patients. Which, the results mostly contradict with each other. Therefore, this review article has been conducted.

Does garlic improve lipid profile and blood glucose in diabetic patients?

Study design:
This review article included 33 articles with a total of 1,273 individuals, with a mean of 39 samples per study.

Results and conclusions:
The investigators found the concentration of serum total cholesterol significantly decreased wih 16.87 mg/dL [95% CI = -21.01 to -12.73, p = 0.001] in the garlic group when compared with the placebo group.

The investigators found the concentration of serum LDL cholesterol (bad cholesterol) significantly decreased with 9.65 mg/dL [95% CI = -15.07 to -4.23, p = 0.001] in the garlic group when compared with the placebo group.

The investigators found the concentration of serum triglycerides significantly decreased with 12.44 mg/dL [95% CI = -18.19 to -6.69, p = 0.001] in the garlic group when compared with the placebo group.

The investigators found the concentration of serum HDL cholesterol (good cholesterol) significantly increased with 3.19 mg/dL [95% CI = 1.85 to 4.53, p = 0.001] in the garlic group when compared with the placebo group.

The investigators found the concentration of serum fasting blood sugar significantly decreased with 10.90 mg/dL [95% CI = -16.40 to -5.40, p = 0.001] in the garlic group when compared with the placebo group.

The investigators found the concentration of serum HbA1c significantly decreased with 0.60 mg/dL [95% CI = -0.98 to -0.22, p = 0.001] in the garlic group when compared with the placebo group.

The investigators concluded that garlic improves lipid profile as well as glucose parameters and can be therapeutically effective in patients suffering from cardiovascular diseases and diabetes.

Original title:
The effect of garlic on lipid profile and glucose parameters in diabetic patients: A systematic review and meta-analysis by Shabani E, Sayemiri K and Mohammadpour M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30049636

Additional information of El Mondo:
Find more information/studies on diabetes, cholesterol, meta-analyses/heterogeneity and garlic right here.

 

Objectives:
The purpose of this review article is to review previously published meta-analyses on the effectiveness of dietary fiber on type 2 diabetes.

Study design:
This umbrella review article included 16 meta-analyses.

Results and conclusions:
The investigators found in the meta-analyses when comparing highest versus lowest dietary fiber intake, a statistically significant reduced risk of 15 to 19% [RR = 0.81-0.85] for type 2 diabetes. However, statistically significant heterogeneity was observed in all of these meta-analyses.

The investigators found in the meta-analyses when comparing highest versus lowest dietary cereal fibers, a statistically significant reduced risk of 13 to 33% [RR = 0.67-0.87] for type 2 diabetes. However, statistically significant heterogeneity was observed in all of these meta-analyses.

The investigators found in the meta-analyses of supplementation studies using β-glucan or psyllium fibers on type 2 diabetic participants, statistically significant reductions were identified in both fasting blood glucose concentrations and glycosylated hemoglobin percentages.

The investigators concluded that those consuming the highest amounts of dietary fiber, especially cereal fiber, may benefit from a reduction in the incidence of developing type 2 diabetes. May benefit because statistically significant heterogeneity was observed in all of these meta-analyses.
There also appears to be a small reduction in fasting blood glucose concentration, as well as a small reduction in glycosylated hemoglobin percentage for individuals with type 2 diabetes who add β-glucan or psyllium to their daily dietary intake.

Original title:
Dietary Fiber Intake and Type 2 Diabetes Mellitus: An Umbrella Review of Meta-analyses by McRae MP.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29628808

Additional information of El Mondo:
Find more information/studies on diabetes, meta-analyses/heterogeneity and dietary fiber right here.

 

Objectives:
The association between dietary protein intake and type 2 diabetes risk has been inconsistent in the previous epidemiological studies. Therefore, this review article (meta-analysis) has been conducted.

Is there an association between dietary protein intake and type 2 diabetes risk?

Study design:
This review article included 10 prospective cohort studies with a total of 34,221 type 2 diabetes cases.
No publication bias was detected.

Results and conclusions:
The investigators found after adjustment of potential confounders, a 5% of energy (5 En%) increment from dietary total protein intake was related to a significantly 9% [95 CI = 1.04-1.13, I2 = 42.0%] higher risk of type 2 diabetes. The results were robust in sensitivity analysis.

The investigators found after adjustment of potential confounders, a 5% of energy (5 En%) increment from dietary animal protein intake was related to a significantly 12% [95 CI = 1.08-1.17, I2 = 14.0%] higher risk of type 2 diabetes. The results were robust in sensitivity analysis.

The investigators found after adjustment of potential confounders, a significant U-shaped curve was observed for plant protein intake with the most risk reduction at about 6% of energy from plant protein intake [p nonlinearity = 0.001]. The results were robust in sensitivity analysis.

The investigators concluded that the consumption of protein, particularly animal protein increases risk of type 2 diabetes.

Original title:
Dietary protein intake and risk of type 2 diabetes: a dose-response meta-analysis of prospective studies by Zhao LG, Zhang QL, [...], Xiang YB.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29858629

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

 

Objectives:
The association between coffee consumption and the level of C-reactive protein (CRP) has been evaluated in several epidemiological studies with conflicting results. Therefore, this meta-analysis (systematic review) has been conducted.

Does coffee consumption reduce level of C-reactive protein in humans?

Study design:
This review article included a total of 9 cross-sectional studies.

Results and conclusions:
The investigators found according to the combined standard mean difference (SMD) between the highest and the lowest coffee intake category, coffee consumption was associated with a significantly lower level of serum CRP level [SMD = -0.34, 95% CI = -0.62 to -0.06, p = 0.016].

The investigators found subgroup analysis for CRP marker showed that coffee consumption was associated with a significantly lower level of serum high-sensitivity CRP (hsCRP) [SMD = -0.51, 95% CI = -0.88 to -0.14, p = 0.007], but not standard CRP [SMD = 0.02, 95% CI = -0.28 to 0.32, p = 0.913].

The investigators concluded that coffee consumption is associated with a lower level of serum CRP, particularly serum high-sensitivity CRP. However, more well-designed prospective cohort studies are needed to elaborate the concerned issues further.

Original title:
Is coffee consumption associated with a lower level of serum C-reactive protein? A meta-analysis of observational studies by Zhang Y and Zhang DZ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29405789

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

 

Objectives:
Epidemiological studies exploring the role of flavonoids intake in preventing type 2 diabetes mellitus (T2DM) showed inconsistent results. Therefore, this review article (meta-analysis) has been conducted.

Does flavonoids intake decrease risk of developing type 2 diabetes?

Study design:
This review article included 10 independent cohorts published between 2002 and 2017 with a total of 312,015 participants, of which 19,953 type 2 diabetes cases were identified during the follow-up periods from 4 to 28 years.
All participants were free of type 2 diabetes at baseline (at the beginning of the study), with age ranging from 28 to 75 years.
Dietary flavonoids intake was evaluated using food-frequency questionnaire and type 2 diabetes was frequently ascertained through medical records.
In the original studies, the median intake level of total flavonoids was 8.9 to 501.8 mg/day for the lowest categories and 33.2 to 1452.3 mg/day for the highest categories.
The most commonly adjusted variables included age, sex, total energy intake, body mass index, smoking, alcohol consumption and physical activity.
All included studies had a NOS score of ≥7, with an average score of 7.9, indicating the presence of high methodological quality.

There was no indication of publication bias from visual inspection of the funnel plot, which was further confirmed by Egger test [p = 0.253].

Results and conclusions:
The investigators found when compared with the lowest intake, the highest intake of total flavonoids was associated with a significantly 9% decreased risk of type 2 diabetes [RR = 0.91, 95% CI = 0.86-0.96, I2  =  21%, p =  0.257].
In stratified analyses, the pooled RR for total flavonoids intake was not modified by sample size, sex, follow-up duration and study location.
Leave-one-out sensitivity analysis showed that no individual study had a significant influence on the final result.

The investigators found in subgroup analyses when compared with the lowest intake, the highest intake of anthocyanidins significantly decreased risk of type 2 diabetes with 11% [RR = 0.89, 95% CI = 0.82-0.95].

The investigators found in subgroup analyses when compared with the lowest intake, the highest intake of flavan-3-ols significantly decreased risk of type 2 diabetes with 14% [RR = 0.86, 95% CI = 0.78-0.95].

The investigators found in subgroup analyses when compared with the lowest intake, the highest intake of flavonols significantly decreased risk of type 2 diabetes with 14% [RR = 0.86, 95% CI = 0.80-0.94].

The investigators found in subgroup analyses when compared with the lowest intake, the highest intake of isoflavones significantly decreased risk of type 2 diabetes with 9% [RR = 0.91, 95% CI = 0.84-0.98].

The investigators found in 9 cohort studies a curvilinear relationship between total flavonoids intake and type 2 diabetes risk [p for nonlinearity = 0.042] with a significant risk reduction at an intake of ≥550 mg/day.

The investigators found when assuming a linear association, the risk of type 2 diabetes was reduced by 5% [RR = 0.95, 95% CI = 0.93-0.97] for each 300-mg/day increment in total flavonoids intake.

The investigators concluded that intakes of total flavonoids, particularly ≥550 mg/day, anthocyanidins, flavan-3-ols, flavonols and isoflavones are associated with significantly decreased risks of type 2 diabetes in the highest versus lowest analyses. Additionally, the dose-response analysis suggest a curvilinear relationship of total flavonoids intake with type 2 diabetes risk; when assuming a linear manner, the risk of type 2 diabetes is reduced by 5% for an increment of 300 mg/day in total flavonoids intake.

Original title:
Flavonoids intake and risk of type 2 diabetes mellitus: A meta-analysis of prospective cohort studies by Xu H, Luo J, [...], Wen Q.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5959406/

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

Objectives:
There is an increasing trend in the consumption of poor-quality diets worldwide, contributing to the increase of non-communicable diseases. Diet directly influences physiological composition and subsequently physical health. Studies have shown that dietary macronutrient and energy content can influence the proportion of intramuscular fat (IMF), which mediates various metabolic and endocrine dysfunction. Therefore, this review article has been conducted.

Do different types of dietary macronutrient intake increase the proportion of intramuscular fat?

Study design:
This review article included 13 trials (RCTs, quasi-RCTs, controlled trials, randomized controlled crossover trials or controlled crossover trials).

High-fat diets were diets with a proportion of fat between 38 and 85 En%. Participants in high-fat diets were all young to middle aged adults with ages varying between 18 and 50 years.

Participants in starvation diets (a decrease of 25% calorie from weight maintenance energy requirements) and hypocaloric diets (890 calories per day, until 15% weight reduction) followed the diet for 8 days with a 3-week washout period in between.

Cohen’s criteria were used to determine the effect size of SMDs, where a SMD between 0.2 and 0.5 is small, a SMD between 0.5 and 0.8 is moderate and a SMD above 0.8 is large. SMDs below 0.2 were considered unsubstantial.

Results and conclusions:
The investigators found in 6 studies with in a total of 134 participants receiving a high-fat intervention and 135 people receiving a control intervention, that high-fat diets (38 and 85 En% fat) significantly increased the proportion of intramuscular fat [SMD = 1.24, 95% CI = 0.43-2.05, p  = 0.003, I2 = 87%].  
Sensitivity analysis (excluding studies with a quality value 20, smallest sample size 8 and those that do not specify participant characteristics) showed a significantly SMD of 1.26 [95% CI = 0.23-2.28, p = 0.02]. 

The investigators found diets with an increased proportion of carbohydrates decreased the proportion of intramuscular fat.
However, increasing caloric intake with carbohydrates compared to a standardized diet (55 En% carbohydrates, 30 En% fat and 15 En% protein) increased the proportion of intramuscular fat.

The investigators found starvation diets (a decrease of 25% calorie from weight maintenance energy requirements) increased intramuscular fat stores and hypocaloric diets (890 calories per day, until 15% weight reduction) did not result in any intramuscular fat proportion changes.

The investigators concluded that high-fat diets (38 y 85 En%), excessive caloric intake in the form of carbohydrates and short-term starvation diets are associated with increases in the proportion of intramuscular fat. However, further studies are needed to assess the effects of macronutrient combinations on intramuscular fat and the influence of diet-induced intramuscular fat alterations on health outcomes. In addition, intramuscular fat poses a possibly effective clinical marker of health.

Original title:
The Effects of Diet on the Proportion of Intramuscular Fat in Human Muscle: A Systematic Review and Meta-analysis by Ahmed S, Singh D, [...], Kumbhare D.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5826234/

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

Higher intramuscular fat levels are positively associated with insulin resistance and an increased risk of developing type 2 diabetes.

Objectives:
Observationally, homocysteine is associated with higher risk of diabetes. Folate, which reduces homocysteine, is promising for the prevention and treatment of diabetes. Previous meta-analysis (review) of 3 trials suggested folate might lower hemoglobin A1c (HbA1c). Therefore, this review article (meta-analysis) has been conducted.

Have folic acid supplementation positive effects on insulin resistance and glycemic control, like HbA1c level and fasting glucose level?

Study design:
This review article included 18 RCTs with in total of 21,081 people with/without diabetes.

Results and conclusions:
The investigators found that folic acid (folate) supplementation significantly reduced fasting glucose level with 0.15 mmol/L [95% CI = -0.29 to -0.01]. Significant means that there is an association with a 95% confidence.

The investigators found that folic acid (folate) supplementation significantly reduced homeostatic model assessment-insulin resistance (HOMA-IR) with 0.83 [95% CI = -1.31 to -0.34].

The investigators found that folic acid (folate) supplementation significantly reduced fasting insulin level with 1.94 μIU/mL [95% CI = -3.28 to -0.61].

The investigators found that folic acid (folate) supplementation had no clear effect on diabetes or HbA1c level.

The investigators concluded that folic acid (folate) supplementation reduces both fasting glucose level, fasting insulin level and homeostatic model assessment-insulin resistance (HOMA-IR) but it has no effect on diabetes or HbA1c level.

Original title:
The effects of folate supplementation on glucose metabolism and risk of type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials by Zhao JV, Schooling CM and Zhao JX.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29501221

Additional information of El Mondo:
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Patients with diabetes often have both an increased fasting glucose level, HOMA-IR value and fasting insulin level.

Objectives:
The increasing prevalence of diabetes in the United Kingdom and worldwide calls for new approaches to its management and diets with low glycaemic index have been proposed as a useful means for managing glucose response. However, there are conflicting reports and differences in the results of studies in terms of their effectiveness. Furthermore, the impact of low-glycaemic index diets (low GI-diets) and their long-term use in patients with type 2 diabetes remains unclear. Therefore, this review article (meta-analysis) has been conducted.

Do patients with type 2 diabetes mellitus benefit from low-GI diets?

Study design:
This review article included 6 RCTs.

Results and conclusions:
The investigators found in 2 RCTs that low-glycaemic index (low-GI) diet resulted in a significant improvement in glycated haemoglobin (HbA1c) [0.05]:
low-GI diet Δ = -0.5% [95% CI = -0.61% to -0.39%] vs. high-cereal fibre diet Δ = -0.18% [95% CI = -0.29% to -0.07%] and;
low-GI legume diet Δ = -0.5% [95% = -0.6% to -0.4%] vs. high-wheat fibre diet Δ = -0.3% [95% Cl = -0.4 to -0.2%].

The investigators found in 4 RCTs significant improvements in fasting blood glucose in low-GI diets compared to higher-GI diets or control:
low-GI diet = [150.8 ± 8.7] vs. higher-GI diet = [157.8 ± 10.4 mg/dL, mean ± SD, p = 0.43];
low-GI diet = [127.7] vs. high-cereal fibre diet = [136.8 mg/dL, p = 0.02];
low-GI diet = [6.5 (5.6-8.4)] vs. standard diabetic diet = [6.7 (6.1-7.5 mmol/L), median and interquartile range p > 0.05] and;
low-GI diet = [7.3 ± 0.3] vs. conventional carbohydrate exchange diet = [7.7 ± 0.4 mmol/L, mean ± SEM (Standard Error of Mean), p 0.05].

The investigators concluded that the low-GI diet is more effective in controlling glycated haemoglobin (HbA1c) and fasting blood glucose compared with a higher-GI diet or control in patients with type 2 diabetes. It will useful to evaluate the long-term effectiveness of low-glycaemic index diet in patients with type 2 diabetes.

Original title:
The Effect of Dietary Glycaemic Index on Glycaemia in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials by Ojo O, Ojo OO, [...], Wang XH.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5872791/

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

A low-GI diet is a diet with a lot of products/meals with a low GI.
Products/meals with a low GI are products/meals with a GI-number of 55 or less.
In daily life, products/meals with a low GI contain at least 1.5 grams fiber per 100 kcal. These products and meals contain at least 1.5 grams fiber per 100 kcal.
 

Objectives:
Type 2 diabetes mellitus (T2DM) is one of the most important public health issues. Vitamin K supplementation might have favorable effect on risk factors of T2DM. Therefore, this review article (meta-analysis) has been conducted.

Have vitamin K supplementation favorable effects on risk factors of type 2 diabetes mellitus?

Study design:
This review article included 5 RCTs with in total of 533 participants.

There was no evidence of publication bias.

Results and conclusions:
The investigators found overall, meta-analysis did not show any beneficial effect of vitamin K supplementation on both:
-fasting blood sugar levels [-0.91 mg/dL, 95% CI = -2.57 to 0.76, p = 0.28];
-fasting insulin levels [-0.35 μIU/mL, 95% CI = -1.70 to 1.00, p = 0.61];
-HOMA-IR [-0.06, 95% CI = -0.32 to -0.19, p = 0.63] and
-2-h oral glucose tolerance test [-4.00 mg/dL, 95% CI = -20.00 to 11.99, p = 0.62].

The investigators found sensitivity analysis showed that overall estimates were not affected by elimination of any study.

The investigators concluded that vitamin K supplementation has no significant effect on glycemic control in healthy subjects. However, further studies should be performed on diabetic and pre-diabetic patients to determine the effect of vitamin K supplementation on impaired glycemic control.

Original title:
Effect of Vitamin K Supplementation on Glycemic Control: A Systematic Review and Meta-Analysis of Clinical Trials by Shahdadian F, Mohammadi H and Rouhani M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/29523009

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