The role of tomato products and lycopene in the prevention of gastric cancer: A meta-analysis of epidemiologic studies
Introduction
Although the incidence of gastric cancer has fallen in most western countries, it remains the second most common cause of cancer-related death worldwide. It has been estimated that approximately 1 million patients are newly diagnosed with gastric cancer worldwide each year, which accounts for nearly 10% of all cancer deaths and claims approximately 700,000 lives annually [1], [2]. It may be owing to healthy lifestyles and to improvements in the three important risk factors: prevalence of smoking, poor diet, and infection caused by Helicobacter pylori [3], [4], [5], [6], [7], [8]. A report published in 2007 by the World Cancer Research Fund and the American Institute for Cancer Research on the relationship between diet and cancer suggested that the consumption of certain types of food may be directly related to the development of malignancy including gastric cancer [9].
A increasing evidence has shown that tomatoes and tomato products may decrease the risk of many human malignant tumor such as prostate, ovarian, pancreatic, bladder, breast and gastric cancer [10], [11], [12], [13], [14], [15]. Lycopene is thought to be the active component in tomatoes and tomato products that is responsible for various types of cancer risk reduction, it has been suggested that potent antioxidants, because they reduce oxidative damage, may thereby prevent chronic diseases such as cancer and cardiovascular disease [16], [17]. Although an association between tomatoes, tomato products or lycopene and gastric cancer risk is biologically plausible, epidemiologic studies on this relationship have yielded inconsistent results.
Since 1970s, many epidemiologic studies have been published from different countries reporting on the association between tomatoes, tomato products or lycopene and risk of gastric cancer, but their conclusions have been inconsistent. Therefore, we performed a systematic review and meta-analysis of cohort and case–control studies to summarize available evidence on this issue.
Section snippets
Search strategy
To identify epidemiologic studies of tomatoes, tomato products and lycopene and risk of gastric cancer, we systematically conducted a literature search MEDLINE from January 1966 to June 2012 and Embase for all relevant articles. We used the following medical subject heading terms and/or text words: “carotenoids”, “tomatoes”, “lycopene”, or “diet”, combined with “stomach cancer”, “stomach neoplasm”, “gastric cancer”, or “gastric neoplasm”. We also scanned the reference lists of all retrieved
Results
A total of 17 studies published from 1985 through 2011 were identified in this meta analysis [22], [23], [24], [25], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35], [36], [37], [38]. Of the 17 studies, 5 were population based case–control studies, 6 were hospital-based case–control studies, and 6 were cohort studies. Of these studies, 12 studies were conducted in Europe, two in America, one each in Japan, China, and Uruguay (Table 1, Table 2). Sample sizes ranged from 223 to 82141
Discussion
The important role played by diet in preventing cancer has received much attention in recent years [50], [51]. Findings of this meta-analysis using studies published in recent years support the negative relationship between tomato products consumption and risk of gastric cancer. Overall, an increase in tomato products consumption was associated with statistically significant 36% reduced risks of gastric cancer in the studies.
There was a statistically significant heterogeneity among the 11
References (59)
- et al.
Meta-analysis in clinical trials
Control Clin Trials
(1986) - et al.
Vitamin A, retinol, and carotenoids and the risk of gastric cancer: a prospective cohort study
Am J Clin Nutr
(2007) - et al.
Dietary intake of selected micronutrients and gastric cancer risk: an Italian case–control study
Ann Oncol
(2009) - et al.
Cured meat, vegetables, and beancurd foods in relation to childhood acute leukemia risk: a population based case–control study
BMC Cancer
(2009) - et al.
Lycopene supplementation prevents smoke-induced changes in p53, p53 phosphorylation, cell proliferation, and apoptosis in the gastric mucosa of ferrets
J Nutr
(2006) - et al.
Carotenoid actions and their relation to health and disease
Mol Aspects Med
(2005) - et al.
Effect of total secondary carotenoids extracts from Chiorococcum sp on Helicobacter pylori-infected BALB/c mice
Int Immunopharmacol
(2003) - et al.
Global cancer statistics, 2011
CA Cancer J Clin
(2011) - et al.
Epidemiology of stomach cancer
Methods Mol Biol
(2009) Stomach cancer incidence has halved over past 30 years in Britain
BMJ
(2009)
Helicobacter pylori infection and the development of gastric cancer
N Engl J Med
Ethnic variations in the occurrence of gastroesophageal cancers
J Clin Gastroenterol
Helicobacter pylori eradication to prevent gastric cancer in a high-risk region of China: a randomized controlled trial
JAMA
Alcohol consumption, cigarette smoking and risk of subtypes of esophageal and gastric cancer: a prospective cohort study
Gut
The second World Cancer Research Fund/American Institute for Cancer Research expert report. Food, nutrition, physical activity, and the prevention of cancer: a global perspective
Proc Nutr Soc
Processed meat consumption and stomach cancer risk: a meta-analysis
J Natl Cancer Inst
The role of tomato products and lycopene in the prevention of prostate cancer: a meta-analysis of observational studies
Cancer Epidemiol Biomarkers Prev
Prospetive study of serum micronutrients and ovarian cancer
J Natl Cancer Inst
A case–control study of diet and cancer of the pancreas
Am J Epidemiol
Nutrient intake in relation to bladder cancer among middle-aged men and women
Am J Epidemiol
Relationships of serum carotenoids, retinol, α-tocopherol, and selenium with breast cancer risk: results from a prospective study in Columbia, Missouri (United States)
Cancer Causes Control
Nutrition and gastric cancer risk: an update
Nutr Rev
Tomato lycopene and its role in human health and chronic diseases
CMAJ
Role of antioxidant lycopene in cancer and heart disease
J Am Coll Nutr
Quantitative methods in the review of epidemiologic literature
Epidemiol Rev
Quantifying heterogeneity in a meta-analysis
Stat Med
Bias in meta-analysis detected by a simple, graphical test
BMJ
The role of dietary factors in the intestinal and diffuse histologic subtypes of gastric adenocarcinoma: a case–control study in the U.S
Cancer
Intake of specific carotenoids and flavonoids and the risk of gastric cancer in Spain
Cancer Causes Control
Cited by (52)
The role of carotenoids in bone health—A narrative review
2024, NutritionExtraction and formulation of valuable components from tomato processing by-products
2022, Tomato Processing by-Products: Sustainable ApplicationsTomato and lycopene and multiple health outcomes: Umbrella review
2021, Food ChemistryCitation Excerpt :Additionally, prostate cancer risk decreased by 3.5%–3.6% for each additional 10 μg/dL of serum lycopene (Rowles et al., 2017). Moreover, consumption of large amounts of tomato reduced risk of gastric cancer (OR: 0.73, 95% CI: 0.60, 0.90) (Yang, Yang, Wang, Wang, & Song, 2013). However, dietary lycopene intake and serum lycopene concentration was not associated with the risk of gastric cancer (Yang et al., 2013).
Current knowledge on the health benefits of carotenoids: Focus on the scientific evidence
2021, Global Perspectives on Astaxanthin: From Industrial Production to Food, Health, and Pharmaceutical ApplicationsCarotenoids and their role in cancer prevention
2020, Biochimica et Biophysica Acta - Molecular and Cell Biology of LipidsSources, characteristics and treatment of plant-based food waste
2020, Food Industry Wastes: Assessment and Recuperation of Commodities
- 1
These authors contributed equally.