1.
Coffee Consumption and C-Reactive Protein Levels: A Systematic Review and Meta-Analysis.
Moua, ED, Hu, C, Day, N, Hord, NG, Takata, Y
Nutrients. 2020;(5)
Abstract
Coffee contains bioactive compounds with anti-inflammatory properties, and its consumption may reduce c-reactive protein (CRP) levels, a biomarker of chronic inflammation. A previous meta-analysis reported no overall association between blood CRP level and coffee consumption by modeling the coffee consumption in categories, with substantial heterogeneity. However, the coffee cup volume was not considered. We conducted a systematic review and dose-response meta-analysis investigating the association between coffee consumption and CRP levels reported in previous observational studies. A dose-response meta-analysis was conducted by mixed-effects meta-regression models using the volume of coffee consumed as metric. Eleven studies from three continents were identified using the PubMed database, totaling 61,047 participants. Three studies with the largest sample sizes observed a statistically significant association between coffee and CRP levels, which was inverse among European and United States (US) women and Japanese men (1.3%-5.5% decrease in CRP per 100 mL of coffee consumed) and positive among European men (2.2% increase). Other studies showed no statistically significant associations. When all studies were combined in the dose-response meta-analysis, no statistically significant associations were observed among all participants or when stratified by gender or geographic location, reflecting the conflicting associations reported in the included studies. Further studies are warranted to explore these inconsistent associations.
2.
N-6 Polyunsaturated Fatty Acids and Risk of Cancer: Accumulating Evidence from Prospective Studies.
Kim, Y, Kim, J
Nutrients. 2020;(9)
Abstract
Previous studies on the association between polyunsaturated fatty acids (PUFAs) and cancer have focused on n-3 PUFAs. To investigate the association between intake or blood levels of n-6 PUFAs and cancer, we searched the PubMed and Embase databases up to March 2020 and conducted a meta-analysis. A total of 70 articles were identified. High blood levels of n-6 PUFAs were associated with an 8% lower risk of all cancers (relative risk (RR) = 0.92; 95% confidence interval (CI): 0.86-0.98) compared to low blood levels of n-6 PUFAs. In the subgroup analyses by cancer site, type of n-6 PUFAs, and sex, the inverse associations were strong for breast cancer (RR = 0.87; 95% CI: 0.77-0.98), linoleic acid (LA) (RR = 0.91; 95% CI: 0.82-1.00), and women (RR = 0.88; 95% CI: 0.79-0.97). In the dose-response analysis, a 2% and 3% decrease in the risk of cancer was observed with a 5% increase in blood levels of n-6 PUFAs and LA, respectively. Thus, there was no significant association between n-6 PUFA intake and the risk of cancer. The pooled RR of cancer for the highest versus lowest category of n-6 PUFA intake was 1.02 (95% CI: 0.99-1.05). Evidence from prospective studies indicated that intake of n-6 PUFAs was not significantly associated with risk of cancer, but blood levels of n-6 PUFAs were inversely associated with risk of cancer.
3.
Nutritional Strategies to Optimize Performanceand Recovery in Rowing Athletes.
Kim, J, Kim, EK
Nutrients. 2020;(6)
Abstract
Rowing is a high-intensity sport requiring a high level of aerobic and anaerobic capacity. Although good nutrition is essential for successful performance in a rowing competition, its significance is not sufficiently established. This review aimed to provide nutritional strategies to optimize performance and recovery in rowing athletes based on a literature review. Following the guidelines given in the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA), we performed web searches using online databases (Pubmed, Web of Science, Wiley Online Library, ACS Publications, and SciFinder). Typically, a rowing competition involves a 6-8-min high-intensity exercise on a 2000-m course. The energy required for the exercise is supplied by muscle-stored glycogens, which are derived from carbohydrates. Therefore, rowing athletes can plan their carbohydrate consumption based on the intensity, duration, and type of training they undergo. For effective and safe performance enhancement, rowing athletes can take supplements such as β-alanine, caffeine, β-hydroxy-β-methylbutyric acid (HMB), and beetroot juice (nitrate). An athlete may consume carbohydrate-rich foods or use a carbohydrate mouth rinse. Recovery nutrition is also very important to minimize the risk of injury or unexplained underperformance syndrome (UUPS) from overuse. It must take into account refueling (carbohydrate), rehydration (fluid), and repair (protein). As lightweight rowing athletes often attempt acute weight loss by limiting food and fluid intake to qualify for a competition, they require personalized nutritional strategies and plans based on factors such as their goals and environment. Training and competition performance can be maximized by including nutritional strategies in training plans.