Nutrition and health

Objectives:
Vitamin D levels have been shown to be associated with diabetic retinopathy, however to date, no review has examined the relationship between vitamin D and sight threatening diabetic retinopathy (STDR) and non-sight threatening diabetic retinopathy (NSTDR). Therefore, this review article has been conducted. 

Does vitamin D deficiency (defined as 25(OH)D levels of 20 ng/mL) increase risk of diabetic retinopathy in patients with diabetes?

Study design:
This review article included 11 cross-sectional studies and 1 case-control study with a total of  9,057 participants.
There was no publication bias.

Results and conclusions:
The investigators found vitamin D deficiency significantly increased risk of sight threatening diabetic retinopathy with 80% [OR = 1.80, 95% CI = 1.40 to 2.30, p ≤ 0.001, I2 = 39.39%].
However, this increased risk was not found for non-sight threatening diabetic retinopathy [OR = 1.10, 95% CI = 0.90 to 1.27, p = 0.48, I2 = 30.21%].

The investigators concluded that vitamin D deficiency (defined as 25(OH)D levels of 20 ng/mL)  increases risk of sight threatening diabetic retinopathy but not non-sight threatening diabetic retinopathy. Given the well-reported associations between vitamin D deficiency and other unfavourable outcomes, it is important that vitamin D deficiency is managed appropriately and in a timely manner to reduce the risk of blindness in people with diabetes.

Original title:
Associations between vitamin D status and sight threatening and non-sight threatening diabetic retinopathy: a systematic review and meta-analysis by Trott M, Driscoll R, […], Pardhan S.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9167360/

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

Diabetic retinopathy, also known as diabetic eye disease (DED), is a complication of diabetes, caused by high blood sugar levels damaging the back of the eye (retina). It can cause blindness if left undiagnosed and untreated.

Objectives:
An enhanced risk for cardiovascular disease (CVD) still exists even when patients with type 2 diabetes have tight control on blood sugar. Thus, identification of treatment approaches that address CVD risk factors may be useful for patients beyond the blood sugar management. Although emerging evidence suggests that nuts consumption have beneficial effects on cardiometabolic health, the effects of almond intake in patients with type 2 diabetes are still controversial. Therefore, this review article has been conducted. 

Does almond consumption improve risk factors (cholesterol, triglycerides, fasting plasma glucose, insulin, hemoglobin A1c (HbA1c), body mass index, weight, body fat, systolic and diastolic blood pressure and CRP) of cardiovascular disease in patients with type 2 diabetes?

Study design:
This review article included 9 RCTs.

Results and conclusions:
The investigators found there was a causal relationship between almond dietary intake and a  significant reduction in low-density lipoprotein cholesterol (LDL cholesterol or bad cholesterol) [WMD = -5.28 mg/dL, 95% CI = -9.92 to -0.64, p = 0.026] in patients with type 2 diabetes compared with the control group.
This lowering effect of LDL cholesterol was robust in subgroups with almond consumption >50 g/day and baseline LDL cholesterol level 130 mg/dL.

The investigators found, however, the effect of almond on total cholesterol, triglycerides, high-density lipoprotein cholesterol (HDL cholesterol or good cholesterol), fasting plasma glucose, insulin, HbA1c, body mass index, weight, body fat, systolic and diastolic blood pressure and CRP was not significant compared with the control group.

The investigators concluded that a dietary intake of at least 50 g/d almond decreases causally LDL cholesterol (bad cholesterol) but has no favourable effect on other cardiometabolic outcomes in patients with type 2 diabetes. Further high-quality studies are needed to firmly establish the clinical efficacy of the almond.

Original title:
Effects of almond on cardiometabolic outcomes in patients with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials by Moosavian SP, Rahimlou M, […], Jalili C.

Link:
https://pubmed.ncbi.nlm.nih.gov/35443097/

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

Objectives:
There is some evidence regarding the positive effects of ginger supplementation on metabolic profile in patients with type 2 diabetes (T2DM). However, they are conflicting and therefore, this review article has been conducted. 

Does ginger supplementation improve metabolic profile (FBS, HbA1c, TC, TG, LDL, HDL, SBP and DBP) in patients with type 2 diabetes?

Study design:
This review article included 10 RCTs.

Results and conclusions:
The investigators found pooled meta-analysis showed a significant reduction in fasting blood sugar (FBS) level following ginger supplementation by polling 8 effect sizes [WMD = -18.81, 95% CI = -28.70 to -8.92, I2 = 77.4%].

The investigators found pooled meta-analysis showed a significant reduction in HbA1c level following ginger supplementation by polling 7 effect sizes [WMD = -0.57, 95% CI = -0.93 to -0.20, I2 = 88.6%].

The investigators found pooled meta-analysis showed a significant reduction in systolic blood pressure (SBP) following ginger supplementation by polling 5 effect sizes [WMD = -4.20, 95% CI = -7.64 to -0.77, I2 = 97%].

The investigators found pooled meta-analysis showed a significant reduction in diastolic blood pressure (DBP) following ginger supplementation by polling 5 effect sizes [WMD = -1.61, 95% CI = -3.04 to -0.18, I2 = 93.2%].

The investigators found pooled meta-analysis showed ginger supplementation had no significant influence on lipid profile involving triglyceride (TG), total cholesterol (TC), LDL cholesterol and HDL cholesterol.

The investigators concluded supplementation with ginger reduces fasting blood sugar, HbA1c, systolic blood pressure and diastolic blood pressure in patients with type 2 diabetes. Further large RCTs are required to shed light on this issue.

Original title:
The effect of ginger supplementation on metabolic profiles in patients with type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials by Ebrahimzadeh A, Ebrahimzadeh A, […], Milajerdi A.

Link:
https://pubmed.ncbi.nlm.nih.gov/35031435/

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

Objectives:
Previous meta-analyses identified an inverse association of coffee consumption with the risk of type 2 diabetes. However, an updated meta-analysis is needed because new studies comparing the trends of association for caffeinated and decaffeinated coffee have since been published. Therefore, this review article has been conducted.

Does coffee intake reduce type 2 diabetes risk in a dose-response manner?

Study design:
This review article included 28 prospective cohort studies with 1109272 study participants and 45335 cases of type 2 diabetes. The follow-up duration ranged from 10 months to 20 years.

Results and conclusions:
The investigators found for compared with no or rare coffee consumption, a significant reduced risk of type 2 diabetes of:
8% [RR = 0.92, 95% CI = 0.90-0.94] for 1 cup/day;
15% [RR= 0.85, 95% CI = 0.82-0.88] for 2 cups/day;
21% [RR = 0.79, 95% CI = 0.75-0.83] for 3 cups/day;
25% [RR = 0.75, 95% CI = 0.71-0.80] for 4 cups/day;
29% [RR = 0.71, 95% CI = 0.65-0.76] for 5 cups/day and;
33% [RR = 0.67, 95% CI = 0.61-0.74] for 6 cups/day.

The investigators found a significant decreased risk of type 2 diabetes of 9% [RR = 0.91, 95% CI = 0.89-0.94] for an increasement of 1 cup/day caffeinated coffee and 6% [RR = 0.94, 95% CI = 0.91-0.98] for an increasement of 1 cup/day decaffeinated coffee [p for difference = 0.17].

The investigators concluded coffee consumption is inversely associated with the risk of type 2 diabetes in a dose-response manner. Both caffeinated and decaffeinated coffee is associated with reduced diabetes risk.

Original title:
Caffeinated and decaffeinated coffee consumption and risk of type 2 diabetes: a systematic review and a dose-response meta-analysis by Ding M, Bhupathiraju SN, […], Hu FB.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/24459154

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

Objectives:
The prevalence of obesity and diabetes is increasing among children, adolescents and adults. Although estimates of the efficacy of exercise training on fasting insulin and insulin resistance have been provided for adults, similar estimates have not been provided for youth. Therefore, this review article has been conducted.

Study design:
This review article included 24 trials.

Results and conclusions:
The investigators found a small to moderate effect for exercise training on fasting insulin and improving insulin resistance in youth [Hedges’ d effect size = 0.48, 95% CI = 0.22-0.74, p 0.001 and 0.31, 95% CI = 0.06-0.56, p 0.05, respectively].

The investigators concluded there is evidence to support the use of exercise training in the prevention and treatment of type 2 diabetes in youth.

Original title:
Exercise and Insulin Resistance in Youth: A Meta-Analysis by Fedewa MV, Gist NH, […], Dishman RK.

Link:
http://www.pediatricsdigest.mobi/content/133/1/e163.abstract

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

Objectives:
Does niacine supplementation reduce blood lipids levels in patients with type 2 diabetes mellitus?

Study design:
This review article included randomized controlled trials.

The meta-analysis showed the absence of publication bias and any dose-response relations between niacin and effect size.

There was a significant heterogeneity for the impact of niacin on LDL cholesterol and fasting plasma glucose.

Results and conclusions:
The investigators found niacin supplementation significantly increased HDL cholesterol with 0.27 mmol/L [95% CI = 0.24 to 0.30, p 0.001] in patients with type 2 diabetes mellitus.

The investigators found niacin supplementation significantly reduced LDL cholesterol with 0.250 mmol/L [95% CI = -0.47 to -0.03, p 0.05] in patients with type 2 diabetes mellitus.

The investigators found niacin supplementation significantly reduced triglycerides with 0.39 mmol/L [95% CI = -0.43 to -0.34, p 0.001] in patients with type 2 diabetes mellitus.

The investigators found niacin supplementation significantly increased fasting plasma glucose with 0.085 mmol/L [95% CI = 0.029 to 0.141, p 0.05] compared with controls in patients with long term treatment.

The investigators concluded niacin alone or in combination improves lipid abnormalities in patients with type 2 diabetes mellitus, but requires monitoring of glucose in long term treatment.

Original title:
Effect of niacin on lipids and glucose in patients with type 2 diabetes: A meta-analysis of randomized, controlled clinical trials by Ding Y, Li Y and Wen A.

Link:
http://www.ncbi.nlm.nih.gov/pubmed/25306426

Additional information of El Mondo:
Find more information on niacin (vitamin B3) and diabetes.

Objectives:
Observational studies suggest an association between dietary fiber intake and risk of type 2 diabetes, but the results are inconclusive. Therefore, this review article (meta-analysis) has been conducted.

Does dietary fiber intake reduce risk of type 2 diabetes?

Study design:
This review article included 17 prospective cohort studies of dietary fiber intake and risk of type 2 diabetes involving 19,033 cases and 488,293 participants.

Results and conclusions:
The investigators found total dietary fiber intake significantly reduced risk of type 2 diabetes with 19% [combined RR = 0.81, 95% CI = 0.73-0.90].

The investigators found dietary cereal fiber intake significantly reduced risk of type 2 diabetes with 23% [combined RR = 0.77, 95% CI = 0.69-0.85].

The investigators found dietary fruit fiber intake significantly reduced risk of type 2 diabetes with 6% [combined RR = 0.94, 95% CI = 0.88-0.99].

The investigators found dietary insoluble fiber intake significantly reduced risk of type 2 diabetes with 25% [combined RR = 0.75, 95% CI = 0.63-0.89].

The investigators found a nonlinear relationship of total dietary fiber intake with risk of type 2 diabetes [p for nonlinearity 0.01].

The investigators found dietary fiber intake of 15g per day non-significantly reduced risk of type 2 diabetes with 2% [combined RR = 0.98, 95% CI = 0.90-1.06].

The investigators found dietary fiber intake of 20g per day non-significantly reduced risk of type 2 diabetes with 3% [combined RR = 0.97, 95% CI = 0.87-1.07].

The investigators found dietary fiber intake of 25g per day significantly reduced risk of type 2 diabetes with 11% [combined RR = 0.89, 95% CI = 0.80-0.99].

The investigators found dietary fiber intake of 30g per day significantly reduced risk of type 2 diabetes with 24% [combined RR = 0.76, 95% CI = 0.65-0.88].

The investigators found dietary fiber intake of 35g per day significantly reduced risk of type 2 diabetes with 34% [combined RR = 0.66, 95% CI = 0.53-0.82].

The investigators found that the risk of type 2 diabetes decreased by 6% [combined RR = 0.94, 95% CI = 0.93-0.96] for 2 g/day increment in cereal fiber intake.

The investigators concluded that the intakes of dietary fiber, at least 25g total dietary fiber intake per day reduce risk of type 2 diabetes.

Original title:
Dietary fiber intake and risk of type 2 diabetes: a dose–response analysis of prospective studies by Yao B, Fang H, […], Zhao Y.

Link:
http://link.springer.com/article/10.1007/s10654-013-9876-x

Additional information of El Mondo:
Find more information on fiber and type 2 diabetes right here.