Written by Taylor Woosley, Staff Writer. Results of a large cross-sectional study show an L-shaped non-linear relationship between copper intake and occurrence of stroke, with increased dietary intake of copper resulting in a lower risk of stroke.
Stroke is the second leading cause of death and is one of the major causes of long-term disability globally 1. Stroke is a neurological disorder characterized by blood vessel blockage as a result of clots forming in the heart and migrating from the brain following an irregular heart beat and the clot blocking arteries and vessels. 2. It affects around 14 million people per year, with 5.5 million morbidities occurring annually, with chances of stroke doubling after the age of 55 years 3. Stroke survivors are at a higher risk for cognitive impairment due to the lack of oxygen delivery to the brain.
Recent research has focused on the use of trace elements as a possible method for reducing the risk of stroke. In particular, copper, one of the most common metals in the human body with large amounts being present in the brain, has been observed for its potential neuroprotective effects against stroke incidence. Copper is an essential element necessary in animals and humans for proper organ function and metabolic processes such as cellular respiration, hemoglobin synthesis, as a neurotransmitter for iron oxidation, and to create the antioxidant defense peptide amidation 4. In addition, copper acts as a cofactor of certain enzymes and is crucial in forming proper protein conformations 5. Copper can be found in a variety of foods such as organ meat, shellfish, seeds, and beans. Copper insufficiency, whether from a poor diet or malabsorption, can lead to disruption of several molecular level pathways and processes 6.
In this large cross-sectional study, the association between copper intake and stroke risk was assessed using data gathered from the NHANES (a large-scale, nationally representative study of the American population). 10,550 participants (age range of 20-80 years, with a mean age of 50 ± 17.35 years) were used in this study with data such as demographic background, dietary intake, and questionnaire data being provided. Average copper intake was attained through two 24-h recalls for analysis. Covariates of interest that were included in this analysis are sex, age, race, marital status, education level, HDL levels, trouble sleeping, and general health. After comparing the data of participants, the observed associations were as follows:
- When examining the influence of covariates, all covariates were associated with stroke (p<0.05), except for sex and HDL.
- Compared to the Mexican American group, subjects in non-Hispanic white, non-Hispanic black, and other race groups had a 1.68-1.89-, and 1.72-times higher risk of stroke (p<0.05).
- The association between copper intake and stroke risk was more significant in female individuals (p=0.002).
- Additionally, the association between copper intake and stroke risk was more significant in individuals aged <65 years old (p=0.013), participants with hypertension (p=0.002), individuals who smoke (p=0.27), and individuals with diabetes (p=0.013).
- The risk of stroke decreased with increased copper intake and displayed a non-linear relationship (p for nonlinear<0.001).
In conclusion, results of the NHANES data show that increased copper intake may decrease incidence of stroke. Other covariates (diabetes, high blood pressure, high HDL levels) also played a role in the occurrence of strokes. Limitations of the study include the potential for recall bias for dietary copper intake, the difference of copper content consumed based on nutritional food differences depending on location, potential incorrect data related to stroke history due to the self-reported nature of the data, and the lack of inclusion of other dietary types and its affect on stroke incidence. Further research should examine how copper, along with other dietary types such as fiber, play a role in the development or the decreased occurrence of strokes.
Source: Yang, Lixiang, Xun Chen, Huilin Cheng, and Lihua Zhang. “Dietary Copper Intake and Risk of Stroke in Adults: A Case-Control Study Based on National Health and Nutrition Examination Survey 2013–2018.” Nutrients 14, no. 3 (2022): 409.
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).
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Posted March 25, 2022.
Taylor Woosley studied biology at Purdue University before becoming a 2016 graduate of Columbia College Chicago with a major in Writing. She currently resides in Glen Ellyn, IL.
References:
- Mirończuk A, Kapica-Topczewska K, Socha K, et al. Selenium, Copper, Zinc Concentrations and Cu/Zn, Cu/Se Molar Ratios in the Serum of Patients with Acute Ischemic Stroke in Northeastern Poland-A New Insight into Stroke Pathophysiology. Nutrients. Jun 22 2021;13(7)doi:10.3390/nu13072139
- Iadecola C, Buckwalter MS, Anrather J. Immune responses to stroke: mechanisms, modulation, and therapeutic potential. J Clin Invest. Jun 1 2020;130(6):2777-2788. doi:10.1172/jci135530
- Kuriakose D, Xiao Z. Pathophysiology and Treatment of Stroke: Present Status and Future Perspectives. Int J Mol Sci. Oct 15 2020;21(20)doi:10.3390/ijms21207609
- Myint ZW, Oo TH, Thein KZ, Tun AM, Saeed H. Copper deficiency anemia: review article. Ann Hematol. Sep 2018;97(9):1527-1534. doi:10.1007/s00277-018-3407-5
- Shi H, Jiang Y, Yang Y, Peng Y, Li C. Copper metabolism in Saccharomyces cerevisiae: an update. Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine. Feb 2021;34(1):3-14. doi:10.1007/s10534-020-00264-y
- Morrell A, Tallino S, Yu L, Burkhead JL. The role of insufficient copper in lipid synthesis and fatty-liver disease. IUBMB Life. Apr 2017;69(4):263-270. doi:10.1002/iub.1613
