4-methylimidazole (4-MEI) is widely used industrially. This carcinogenic component has been reported in some types of food. It is usually produced by the caramelization process in food, drinks and caramel coloring. The possible mechanism for the formation of this compound in food is the Maillard reaction. In order to estimate the amount of substance 4-MEI in food, a systematic study was conducted. The selected keywords were 4-methylimidazole, 4-MEI, beverage, drink, meat, milk, and coffee. 144 articles were obtained from the initial search. The articles were evaluated and finally, the data of 15 manuscripts were extracted. Based on the data extracted from selected articles, the highest amount is reported in caramel color, coffee, and cola drinks. In 70% of the selected studies, the analytical method was based on liquid chromatography. In this method, there is no need for derivatization. SPE columns were used to extract samples in most manuscripts. According to per capita consumption, the most exposure to 4-MEI is through coffee. In high risk food products, regular monitoring with analytical methods with high sensitivity is recommended. Furthermore, most of the selected studies were about the validation method, so few samples were selected. It is recommended to design more studies with a high sample size to accurately evaluate this carcinogenic compound in food.

The aim of this systematic review was to provide the required information regarding different aspects of the relationship between epilepsy/antiseizure medications and non-alcoholic drinks. The recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement were followed. MEDLINE and Scopus from the inception until 7 August 2021 were systematically searched. These key words were used: \"epilepsy\" OR \"seizure\" OR \"antiepileptic\" OR \"antiseizure\" OR \"anticonvulsant\" AND \"coffee\" OR \"tea\" OR \"soda\" OR \"juice\" OR \"drink\" OR \"cola\" OR \"diet\" (35 key word combinations). The primary search yielded 21 458 publications (PubMed, n = 4778; Scopus, n = 16 680). Only 50 studies met all the inclusion criteria and were included in the current systematic review. In total, 17 articles investigated various non-alcoholic drinks in human studies, 11 studies were case reports/series, and 22 articles were animal/in vitro studies. None of the studies provided a class 1 of evidence. There is limited evidence suggesting that certain drinks (eg, caffeinated energy drinks) might trigger seizures. Patients with epilepsy should avoid excessive consumption of certain fruit juices (eg, grapefruit, lime, pomegranate, kinnow, and star fruit) and caffeinated drinks. However, daily coffee and tea intake can be part of a healthy balanced diet, and their consumption does not need to be stopped in patients with epilepsy. Coffee/tea consumption is not harmful if consumed at levels of 200 mg (caffeine) in one sitting (about 2½ cups of coffee) or 400 mg daily (about five cups of coffee).

Controversial results of the association between green tea consumption and risk for esophageal cancer (EC) were reported by previous meta-analysis. Thus, the aim of this study was to quantitatively investigate the association.
The Cochrane Library, PubMed, and EMBASE databases were searched for relevant studies. We used a \"one-stage approach\" with a restricted cubic spline model to summarize the dose-specific relationships between green tea and risk for EC. Odds ratios (ORs) were used to measure the effects. Fourteen studies were included with a total of 5057 ECs among 493 332 participants.
In the dose-response analysis, the summary OR for a 1 cup/d increase in green tea was 1.00 (95% confidence interval [CI], 0.95-1.04; I2 = 77%). No nonlinearity association was observed between tea consumption and risk for EC (P = 0.71 for nonlinearity). In the subgroup of sex, the summary OR for a 1 cup/d increase in green tea was 1.03 (95% CI, 0.95-1.11, I2 = 67%) for men and 0.79 (95% CI, 0.68-0.91; I2 = 0%) for women.
Contrary to previous studies, based on current evidence, the present dose-response study suggested no association between green tea and risk for EC. However, there might be a protective effect of green tea in women. Notably, our conclusion might be influenced by limited studies and potential bias, such as dose of green tea assessment and select bias of case-control studies. Further larger number, prospective, and well-designed larger-scale studies are needed to provide more precise evidence, especially in women and more regions (United States and Europe).

Results from earlier publications on the association of coffee and caffeine and risk of ovarian cancer are inconsistent.
To evaluate the link between coffee, caffeine, caffeinated coffee, and decaffeinated coffee consumption and risk of ovarian cancer.
We searched PubMed/Medline, ISI Web of Science, Scopus, and Google Scholar to identify relevant publications up to April 2018. All case-control studies that considered coffee, caffeine, caffeinated coffee, or decaffeinated coffee as the exposure variables and ovarian cancer as the main outcome variable or as one of the outcomes were included in the systematic review. Publications in which odds ratios (ORs) or rate or risk ratios (RRs) and 95% confidence intervals (CIs) were reported, were included in the meta-analysis.
A total of 22 case-control studies were included in the systematic review, and 20 studies in the meta-analysis. Overall, 40 140 participants, including 8568 patients with ovarian cancer, aged ≥ 17 years were included. Combining 21 effect sizes from 18 studies, no significant association was observed between total coffee intake and risk of ovarian cancer (OR=1.09; 95% CI 0.94 to 1.26). There was no significant association between total caffeine intake and ovarian cancer risk (OR=0.89; 95% CI 0.55 to 1.45). In addition, caffeinated coffee intake was not significantly associated with ovarian cancer (OR=1.05; 95% CI 0.87 to 1.28). However, combining effect sizes from five studies, we found an inverse significant association between decaffeinated coffee intake and risk of ovarian cancer (OR=0.72; 95% CI 0.58 to 0.90).
Our findings indicated an inverse association between decaffeinated coffee consumption and risk of ovarian cancer. No significant association was found between coffee, caffeine or caffeinated coffee intake and risk of ovarian cancer.