This tab will answer the following nutritional question: How can nutrition contribute positively to my health?

One swallow does not make a summer. A famous Dutch saying that could not be any more obvious. Just because one single scientific study about a certain topic makes certain claims, it does not necessarily mean it is true. On the other hand, a review article (a collection of scientific studies on a certain topic) of randomized, placebo-controlled double blind clinical trials (RCTs) will answer the following question:
"Do taking dietary supplements make sense?" Yes for a positive conclusion and no for a negative conclusion.

One swallow does not make a summer. A famous Dutch saying that could not be any more obvious. Just because one single scientific study about a certain topic makes certain claims, it does not necessarily mean it is true. On the other hand, a review article (a collection of scientific studies on a certain topic) of cohort studies or case-control studies will answer the following question:
"Should I change my diet?".

Find scientific studies on vitamin A: type vitamin A in Search field.

Nutrition and health

Elevated serum selenium levels may decrease high-grade prostate cancer among current and former smokers

Objectives:
Some observational studies have shown that elevated serum selenium levels are associated with reduced prostate cancer risk. However, not all published studies support these results. Therefore, this review article (meta-analysis) has been conducted.

Does an elevated serum selenium level reduce prostate cancer risk?

Study design:
This review article included 12 case-control studies, 4 cohort studies and 1 RCT with 6,136 prostate cancer cases among 34,901 participants.

Results and conclusions:
The investigators found elevated serum selenium levels significantly decreased prostate cancer risk with 24% [pooled OR = 0.76, 95% CI = 0.64 to 0.91, I2 = 60.8%, p = 0.001]. Significant means that there is an association with a 95% confidence.

The investigators found in subgroup analysis, an inverse association between elevated serum selenium levels and prostate cancer risk in case-control studies, current and former smokers, high-grade cancer cases, advanced cancer cases and different populations. However, such correlations were not found among cohort studies, nonsmokers, low-grade cancer cases and early stage cancer cases.

The investigators concluded that elevated serum selenium levels may decrease high-grade prostate cancer among current and former smokers. May decrease because the inverse relationship between elevated serum selenium levels and prostate cancer risk was not significant among cohort studies. Therefore, further cohort studies and randomized control trials based on non-Western populations are required.

Original title:
Serum selenium levels and prostate cancer risk: A MOOSE-compliant meta-analysis by Cui Z, Liu D, […], Liu G.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5293444/

Additional information of El Mondo:
Find more information/studies on selenium and cancer right here.

Vitamin C and D reduce blood pressure in patients with type 2 diabetes

Objectives:
Is there an association between individual micronutrients and blood pressure in patients with type 2 diabetes?

Study design:
This review article included 11 RCTs (13 interventions, 723 patients with type 2 diabetes and ages ranging from 50.7 to 66.8 years and 54% of them were males. The duration of diabetes varied from 4.6 to 8.6 years) with 3 to 52 weeks of follow-up were classified according to the type of micronutrient intervention: sodium (n = 1), vitamin C (n = 2), vitamin D (n = 7) and magnesium (n = 1).
Only a meta-analysis of vitamin C and D was able to perform with the available data.

Results and conclusions:
The investigators found vitamin C significantly reduced diastolic blood pressure of patients with type 2 diabetes with 2.88mmHg [WMD = -2.88 mmHg, 95% CI = -5.31 to -0.46, p = 0.020].
However, vitamin C not significantly reduced systolic blood pressure [WMD = -3.93mmHg, 95% CI = -14.78 to 6.92, p = 0.478].
Significant means that there is an association with a 95% confidence.

The investigators found vitamin D significantly reduced diastolic blood pressure of patients with type 2 diabetes with 2.44mmHg [WMD = -2.44 mmHg, 95% CI = -3.49 to -1.39, p 0.001].

The investigators found vitamin D significantly reduced systolic blood pressure of patients with type 2 diabetes with 4.56mmHg [WMD = -4.56 mmHg, 95% CI = -7.65 to -1.47, p = 0.004].

The investigators concluded vitamin D and possibly vitamin C have beneficial effects on blood pressure in patients with type 2 diabetes. Therefore, these interventions might represent a novel approach to the treatment of hypertension in patients with type 2 diabetes.

Original title:
Effects of individual micronutrients on blood pressure in patients with type 2 diabetes: a systematic review and meta-analysis of randomized clinical trials by de Paula TP, Kramer CK, [...], Azevedo MJ.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5233957/

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