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

Diabetes increases risk of dementia and mild cognitive impairment

Objectives:
Does diabetes increase risk of incident dementia and mild cognitive impairment?

Study design:
This review article included 19 prospective longitudinal studies including 6184 subjects with diabetes and 38530 subjects without diabetes. All subjects were without dementia or mild cognitive impairment at baseline (=at the beginning of the study).

There was no publication bias.

Results and conclusions:
The investigators found persons with diabetes had a significant increased risk of 46% for Alzheimer's disease [RR = 1.46, 95% CI = 1.20-1.77]. Significant means that there is an association with a 95% confidence.

The investigators found persons with diabetes had a significant increased risk of 148% for vascular dementia [RR = 2.48, 95% CI = 2.08-2.96].

The investigators found persons with diabetes had a significant increased risk of 51% for any dementia [RR = 1.51, 95% CI = 1.31-1.74]. Significant because RR of 1 was not found in the 95% CI of 1.31 to 1.74. RR of 1 means no risk/association.

The investigators found persons with diabetes had a significant increased risk of 21% for mild cognitive impairment [RR = 1.21, 95% CI = 1.02-1.45].

The investigators concluded diabetes is a risk factor for incident dementia (including Alzheimer's disease, vascular dementia and any dementia) and mild cognitive impairment.

Original title:
Diabetes as a risk factor for dementia and mild cognitive impairment: a meta-analysis of longitudinal studies by Cheng G, Huang G, [...], Wang H.

Link:
http://onlinelibrary.wiley.com/doi/10.1111/j.1445-5994.2012.02758.x/epdf

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

Garlic supplementation during 12 weeks reduces fasting blood glucose

Objectives:
Garlic is a common spicy flavouring agent also used for certain therapeutic purposes. Garlic's effects on blood glucose have been the subject of many clinical and animal studies. However, studies reporting hypoglycemic effects of garlic in humans are conflicting. Therefore, this review article (meta-analysis) has been conducted.

Has garlic supplementation lowering effects on glycemic control measurements such as fasting blood glucose (FBG), postprandial glucose (PPG) and glycated haemoglobin (HbA1c)?

Study design:
This review article included a total of 7 RCTs (parallel design) that involved 9 comparisons with 513 subjects. The trials varied in size from 33 to 180 subjects. The study duration varied from 4 to 24 week (median: 12 week). The trials enrolled male and female subjects, both healthy and with diabetes.

Doses of garlic in the treatment group ranged from 600 to 1500 mg/d.

Results and conclusions:
The investigators found pooled analyses showed that garlic supplementation resulted in a statistically significant lowering in fasting blood glucose [SMD = -1.67, 95% CI = -2.80 to -0.55, p = 0.004].

The investigators could not perform a pooled analyse for postprandial glucose (PPG) control and glycosylated haemoglobin (HbA1c) outcomes, because only 1 study included in the meta-analysis reported PPG variables and only 2 studies reported HbA1c variables.

The investigators concluded that garlic supplementation (600 to 1500 mg/d) during 12 weeks results in a lowering in fasting blood glucose. More trials are needed to investigate the effectiveness of garlic on HbA1c and PPG.

Original title:
Garlic intake lowers fasting blood glucose: meta-analysis of randomized controlled trials by Hou LQ, Liu YH and Zhang YY.

Link:
http://apjcn.nhri.org.tw/server/APJCN/24/4/575.pdf

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