FOLSOM, Calif., February 9, 2021 - A new animal study, published in the Journal of Clinical Biochemistry and Nutrition, suggests regular walnut consumption may be a promising intervention for reducing negative outcomes associated with Helicobacter pylori (H. pylori) infection, a widespread bacterial infection that affects more than half of the world's population.
Using mice models, researchers from the CHA Cancer Prevention Research Center in Korea found preliminary evidence that eating a diet rich in walnuts may help protect against negative outcomes associated with H. pylori infection. Specifically, the research found that walnut extracts, formed from whole walnuts, may help create protective proteins and anti-inflammatory actions in the gut that may safeguard against H. pylori infection and resulting cancer in mice. The study was supported by the California Walnut Commission.
Prevalence of H. pylori is most common in developing countries as it is generally related to socioeconomic status and hygienic conditions and is thought to be spread through person to person contact or even through food and water. H. pylori infection is a major cause of ulcers in the stomach and small intestine as well as stomach cancer and peptic ulcer disease. While treatments are currently available, there are concerns about the bacteria's growing resistance to antibiotics.
Due to increasing challenges associated with antibiotic resistance, researchers have been investigating dietary and other non-bacterial approaches to improve impact from H. pylori infection, such as in this new study.
This is not the first time walnuts have been linked to a lower risk of gastrointestinal cancer development in mice. Two other animal studies published in Cancer Prevention Research and Nutrients found that walnuts in the diet may suppress colon tumor development by modifying gut bacteria as well as inhibit the progression of colorectal cancer by suppressing angiogenesis - the development of new blood vessels which facilitates the growth of cancer cells.
Animal studies are valuable for providing background information and can be used as a basis for future research in humans. Based on the existing body of evidence, including this study on walnuts, dietary approaches to reduce symptoms of H. pylori infection, such as inflammation, seem worthwhile to pursue in a well-designed clinical trial to confirm the findings.
The California Walnut Commission (CWC) supported this research. The CWC has supported health-related research on walnuts for more than 30 years with the intent to provide knowledge and understanding of the unique health benefits associated with consuming walnuts. While the CWC does provide funds and/or walnuts for various projects, all studies are conducted independently by researchers who design the experiments, interpret the results and present evidence-based conclusions. The CWC is committed to scientific integrity of industry-funded research.
The California walnut industry is made up of more than 4,500 growers and approximately 85 handlers (processors). The growers and handlers are represented by two entities, the California Walnut Board (CWB) and the California Walnut Commission (CWC).
California Walnut Commission
The California Walnut Commission, established in 1987, is funded by mandatory assessments of the growers. The CWC represents more than 4,500 growers and approximately 85 handlers (processors) of California walnuts in export market development activities and conducts health research. The CWC is an agency of the State of California that works in concurrence with the Secretary of the California Department of Food and Agriculture (CDFA).
The CWC prohibits discrimination in all programs and activities on the basis of race, color, national origin, age, disability, sex, marital/familial/parental status, religion, sexual orientation, political beliefs, reprisal or retaliation for prior civil rights activity, or because all or part of an individual's income is derived from any public assistance programs.
Persons with limited English proficiency or disabilities who require alternative means for communication of program information (translated materials, braille, large print, audiotape, etc.) should contact the CWC offices at (916) 932-7070.
To file a complaint of discrimination, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at http://www.
Park JM, Han YM, Park YJ, et al. Dietary intake of walnut prevented Helicobacter pylori-associated gastric cancer through rejuvenation of chronic atrophic gastritis. J Clin Biochem Nutr. 2021;68(1):37-50. doi:10.3164/jcbn.20-103
Hooi JKY, Lai WY, Ng WK, et al. Global Prevalence of Helicobacter pylori Infection: Systematic Review and Meta-Analysis. Gastroenterology. 2017;153(2):420-429. doi:10.1053/j.gastro.2017.04.022
Fahey JW, Stephenson KK, Wallace AJ. Dietary amelioration of Helicobacter infection. Nutr Res. 2015;35(6):461-473. doi:10.1016/j.nutres.2015.03.001
Nakanishi M, Chen Y, Qendro V, et al. Effects of walnut consumption on colon carcinogenesis and microbial community structure. Cancer Prev Res (Phila). 2016;9(8):692-703.
Nagel JM, Brinkoetter M, Magkos F, et al. Dietary walnuts inhibit colorectal cancer growth in mice by suppressing angiogenesis. Nutrition. 2012;28(1):67-75.