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- "The British Journal of Nutrition"; Consumption of Brown Onions Moderately Modulates Blood Lipids Haematological and Haemostatic Variables in Healthy Pigs; E. Ostrowska, et al.; 2004
- "The British Journal of Nutrition"; Consumption of Brown Onions Moderately Modulates Blood Lipids Haematological and Haemostatic Variables in Healthy Pigs; E. Ostrowska, et al.; 2004
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Do Onions Thin Blood?
Onions can thin your blood because they contain flavonoids. Certain flavonoids, such as quercetin, which is found in onions, are antioxidants. This means that onions may be able to protect you against free radicals that could otherwise damage cell tissues within your body. Onions should not be used to replace any blood thinners you are on or cure any specific conditions. Talk to your doctor about the use and ingestion of onions prior to using them medicinally.
If you are experiencing serious medical symptoms, seek emergency treatment immediately.
Hypertension
Quercetin only belongs to a group of plant pigments called flavonoids. This is what gives various fruits, flowers and vegetables their color. The University of Maryland Medical Center recognizes that quercetin supplementation helps reduce blood pressure in those who suffer from hypertension 3. Quercetin aids in hypertension by thinning the blood, which is why onions can be useful to those who suffer from hypertension.
- Quercetin only belongs to a group of plant pigments called flavonoids.
- Quercetin aids in hypertension by thinning the blood, which is why onions can be useful to those who suffer from hypertension.
Blood Thinners
Benefits From Purple Onion Tea
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If you take blood thinners, talk to your doctor about the consumption of onions, quercetin supplements and other foods or supplements that may thin your blood. Quercetin supplements can interfere with prescription and over-the-counter blood thinners such as coumadin, plavix and aspirin, according to the University of Maryland Medical Center 3. Quercetin supplements tend to enhance the effect of blood thinners, increasing the risk of bleeding. Quercetin also may interfere with other medications, such as corticosteroids and chemotherapy drugs, which can prevent your body from absorbing certain medications.
- If you take blood thinners, talk to your doctor about the consumption of onions, quercetin supplements and other foods or supplements that may thin your blood.
- Quercetin supplements can interfere with prescription and over-the-counter blood thinners such as coumadin, plavix and aspirin, according to the University of Maryland Medical Center 3.
Heart Protection
Flavonoids can help protect against high cholesterol and atherosclerosis, which is the plaque buildup in your arteries that can lead to stroke and heart attack. Onions may benefit certain conditions of the heart due to the thinning of blood, making it easier for your heart and circulatory system to pump blood.
Considerations
Nutritional Difference Between Yellow & Red Onions
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Certain types of onions may have a better effect on blood thinning. According to a study conducted by the Department of Primary Industries at the Victorian Institute of Animal Science in Victoria, Australia, brown onions seem to work the best in regards to thinning blood — at least when it comes to testing pig subjects. The Victorian Institute of Animal Science tested various onion supplements, raw brown onions and destiny onions over the course of six weeks. Blood levels were drawn and tested for clotting at various times during the study. The end conclusion is that supplementation of raw brown onions made the most impact in regards to lipid-modulating and immunostimulatory properties.
- Certain types of onions may have a better effect on blood thinning.
- The end conclusion is that supplementation of raw brown onions made the most impact in regards to lipid-modulating and immunostimulatory properties.
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References
- Drugs.com: Complete Onion Information; 2011
- "The British Journal of Nutrition"; Consumption of Brown Onions Moderately Modulates Blood Lipids Haematological and Haemostatic Variables in Healthy Pigs; E. Ostrowska, et al.; 2004
- University of Maryland Medical Center: Quercetin; 2009
- Onions, raw. FoodData Central. U.S. Department of Agriculture. Published April 1, 2019.
- Anderson GH, Soeandy CD, Smith CE. White vegetables: Glycemia and satiety. Adv Nutr. 2013;4(3):356S-67S. doi:10.3945/an.112.003509
- Exploring aromatics. Academy of Nutrition and Dietetics. Updated 2020.
- Dabeek WM, Marra MV. Dietary quercetin and kaempferol: Bioavailability and potential cardiovascular-related bioactivity in humans. Nutrients. 2019;11(10). doi:10.3390/nu11102288
- Puccinelli MT, Stan SD. Dietary bioactive diallyl trisulfide in cancer prevention and treatment. Int J Mol Sci. 2017;18(8). doi:10.3390/ijms18081645
- Marrelli M, Amodeo V, Statti G, Conforti F. Biological properties and bioactive components of Allium cepa L.: Focus on potential benefits in the treatment of obesity and related comorbidities. Molecules. 2018;24(1). doi:10.3390/molecules24010119
- Chae MR, Kang SJ, Lee KP, et al. Onion (Allium cepa L.) peel extract (OPE) regulates human sperm motility via protein kinase C-mediated activation of the human voltage-gated proton channel. Andrology. 2017;5(5):979-989. doi:10.1111/andr.12406
- Smith AP, Sutherland D, Hewlett P. An investigation of the acute effects of oligofructose-enriched inulin on subjective wellbeing, mood and cognitive performance. Nutrients. 2015;7(11):8887-96. doi:10.3390/nu7115441
- Albanesi M, Pasculli C, Giliberti L, et al. Immunological characterization of onion (Allium cepa) allergy. Postepy Dermatol Alergol. 2019;36(1):98-103. doi:10.5114/ada.2019.82829
- Cooking with onions without crying. University of Nebraska-Lincoln. Updated 2020.
- What is the low FODMAP diet?. Academy of Nutrition and Dietetics. Updated 2019.
- Onions. RxList. Updated 2019.
- Shock CC, Cheatham NE, Harden JL, Mahony, AC, Shock BM. Types of onions and varieties. Oregon State University. College of Agricultural Sciences. Updated 2020.
- Dowdy S. Stored properly Vidalia onions can still be around this winter. University of Georgia. College of Agriculture and Environmental Science. Updated 2019.
Writer Bio
Derek Buckner has been writing professionally since 2005, specializing in diet, nutrition and general health. He has been published in "Today's Dietitian," "Food Essentials" and "Eating Well Magazine," among others. Buckner is a registered dietitian and holds a Bachelor of Science in nutrition and food science from Drexel University.