Objectives:
Although several meta-analyses have revealed the beneficial effects of dietary fiber intake on human health, some have reported inconsistent findings. Therefore, this umbrella meta-analysis (review article) has been conducted.

Does higher dietary fiber intake improve causally cardiovascular risk factors?

Objectives:
Do COPD patients benefit from vitamin C supplementation?

Study design:
This review article included 10 RCTs with a total of 487 patients.

Results and conclusions:
The investigators found that vitamin C supplementation (≥400 mg/day) significantly improved the forced expiratory volume in one second as a percentage (FEV1%) of COPD patients [SMD = 1.08, 95% CI = 0.03 to 2.12, p = 0.04].

Objectives:
Do plant-based diets improve age-related ocular outcomes among adults?

Study design:
This review article included 15 studies (n = 51,695 participants) assessed the impact of fish consumption, 8 studies (n = 28,753 participants) analyzed the effect of red meat intake and 3 studies (n = 7,723 participants) assessed the impact of omission of skim milk, poultry and non-meat animal products and the presence of disease incidence as indicated by age-related macular degeneration or cataract development.

Objectives:
Undernutrition is a major risk factor for tuberculosis (TB), which is estimated to be responsible for 1.9 million TB cases per year globally. The effectiveness of micronutrient supplementation on TB treatment outcomes and its prognostic markers (sputum conversion, serum zinc, retinol and haemoglobin levels) has been poorly understood. Therefore, this review article has been conducted.

Objectives:
There is keen interest in better understanding the impacts of alpha-linolenic acid (ALA), a plant-derived n-3 fatty acid, in ameliorating the development of cancer. However, results of several prospective cohort studies present an inconsistent association between ALA intake and the incident colorectal cancer (CRC). Therefore, this review article has been conducted.

Objectives:
Dementia is a chronic progressive neurodegenerative disease that can lead to disability and death in humans, but there is still no effective prevention and treatment. Due to the neuroprotective effects of vitamin E, a large number of researchers have explored whether vitamin E can reduce the risk of dementia. Some researchers believe that vitamin E can reduce the risk of dementia, while others hold the opposite conclusion. Therefore, this review article has been conducted.

Objectives:
What is the incremental net benefit (INB) of the 13-valent PCV (PCV13) and 10-valent PCV (PCV10) in children?

Study design:
This review article included 70 studies.

Objectives:
Does consumption of fruits and vegetables reduce risk of endometrial cancer?

Study design:
This review article included  of 21 case-control studies and 6 cohort studies.

Results and conclusions:
The investigators found that vegetables consumption significantly reduced risk of endometrial cancer with 24% [pooled odds ratio [OR], relative risk [RR], hazard ratio [HR] = 0.76, 95% CI = 0.63 to 0.91].

Objectives:
Previous studies on the effect of Brassica vegetables on blood glucose and lipid profile have reported inconclusive findings. Therefore, this meta-analysis (review article) has been conducted.

Does higher Brassica vegetables consumption improve causally cardiovascular risk factors (levels of triglycerides, cholesterol, fasting blood sugar and glycated haemoglobin)?

Study design:
This review article included 9 RCTs with a total of 548 participants.

Objectives:
Inflammation is a major cause of chronic diseases. Several studies have investigated the effects of tomato intake on inflammatory biomarkers; however, the results are equivocal. Therefore, this review article has been conducted.

Does tomato intake have positive impact on inflammatory biomarkers in adults?

Study design:
This review article included 7 RCTs (8 treatment arms) with a total of 465 subjects.