Objectives:
Essential amino acids (EAAs) promote the process of regulating muscle synthesis. Thus, whey protein that contains higher amounts of essential amino acids can have a considerable effect on modifying muscle synthesis. However, there is insufficient evidence regarding the effect of soya and whey protein supplementation on body composition. Therefore, this review article has been conducted.

Objectives:
Several underlying diseases have been associated with unfavorable COVID-19 related outcomes including asthma and Chronic Obstructive Pulmonary Disease (COPD), however few studies have reported risks that are adjusted for confounding variables. Therefore, this review article has been conducted.

Are COPD and asthma associated with COVID-19 related hospital admission, intensive care unit (ICU) admission and mortality?

Study design:
This review article included 37 studies with a total of 1,678,992 participants.

Objectives:

Objectives:
Does a high BMI increase liver cancer mortality and occurrence of primary liver cancer?

Study design:
This review article included 28 prospective cohort studies with 8,135,906 subjects, of which 6,059,561 subjects (persons) with primary liver cancer occurrence and 2,077,425 subjects with liver cancer-related mortality.

Results and conclusions:

Objectives:
Systemic inflammation and oxidative stress (OS) are associated with breast cancer. Coenzyme Q10 (CoQ10) as an adjuvant treatment with conventional anti-cancer chemotherapy has been demonstrated to help in the inflammatory process and oxidative stress. Therefore, this review article has been conducted.

Objectives:
What is the overall vaccine effectiveness of the BNT162b2 mRNA vaccine (Pfizer-BioNTech COVID 19 mRNA vaccine) from observational studies?

Study design:
This review article included 19 observational studies.
The vaccine effectiveness was indicated as (pooled HR - 1)/HR or (pooled IRR - 1)/IRR.

Results and conclusions:   

Objectives:
Undernutrition, defined as stunting, wasting and underweight, still implicates millions of infants and children worldwide. Micronutrients have pivotal effects on growth rate. The outcomes of vitamin D deficiency on undernutrition indices have stayed controversial. Therefore, this review article has been conducted.

Objectives:
Does guarana supplementation reduce cancer-related fatigue?

Study design:
This review article included 7 RCTs with a total of 427 cancer patients.
Some studies presented a low risk of bias for all the categories.
Meta-analysis was conducted for 3 studies about breast cancer, which presented sufficient data.

The instruments used to analyze fatigue were the Brief Fatigue Inventory (BFI), the Chalder Fatigue Scale, the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-FATIGUE) and the Piper Scale.

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:

Objectives:
Do higher CK-MB concentrations (CK-MB is a biomarker of myocardial injury)  increase risk of severity and mortality in COVID-19 patients?

Study design:
This review article included 55 studies with 11,791 COVID-19 patients.
9,596 (48% males, mean age 54 years) with low severity or survivor status and 2,195 (62% males, mean age 66 years) with high severity or non-survivor status during follow up.

Begg's [p ​= ​0.50] and Egger's [p ​= ​0.86] t-tests did not show publication bias.