Only animal products – meat, chicken, fish, eggs, milk and cheese – contain dietary cholesterol. Red onions and other plant foods do not contain cholesterol. But including red onions may improve your cholesterol levels, according to limited research. To keep red onions heart-healthy, don’t sauté them in butter or dip onion rings in batter and then deep fry them.
Red Onion Nutrition
A medium onion – red or white – contains 44 calories. It provides 1.21 g of protein, 0.11 g of fat, 10.27 g of carbohydrate and 1.9 g of fiber. A red onion provides calcium, potassium, magnesium, vitamin C and folate. A popular cooking ingredient, red onion is also a common homeopathic remedy used to treat allergies, colds, coughs and bronchitis. Sulfides and flavonoids in red onions as well as their anti-clotting properties may contribute to cardiovascular health.
Raw vs. Blanched Onions
Researchers from Hebrew University in Israel tested the effects of garlic, red onion and white onion on the lipid levels of rats fed a diet high in cholesterol. S. Gorinstein, lead author, stated that red and white onion worked better than garlic in improving cholesterol and arteriosclerosis, or hardening of the arteries. Blanched onions proved more helpful than raw onions, according to the report in the May 2010 issue of “Phytotherapy Research.” Blanching vegetables involves putting them briefly in boiling water. The onions in Gorinstein’s experiment were blanched for 90 seconds.
Triglycerides
Another animal study found that eating onions – any color – helped reduce triglycerides. Triglycerides, like low-density lipoprotein cholesterol, tend to accumulate in your arteries and increase your risk for heart attacks and strokes. N.K. Gabler and other Australian researchers fed pigs a typically high-fat Western diet. They added onions to the diets to some of the pigs. The pigs that ate onions realized a 15-percent reduction in their triglyceride levels, according to the report published in December 2006 in “Plant Foods for Human Nutrition.”
Considerations
If you like red onions, evidence from the two studies might give you incentive to include them more often in your diet. But research remains too slight to recommend eating them exclusively for heart-healthy purposes. To keep your cholesterol at healthy levels, include a wide selection of vegetables, fruits and whole grains in your diet. Limit your consumption of animal products, sugar and alcohol. Maintain a healthy weight and exercise regularly.
References
- United States Department of Agriculture Nutrient Database
- National Center for Complementary and Alternative Medicine; Homeopathy: An Introduction; August 2010
- Vegetarianism and Vegetarian Nutrition; Health Benefits of Onions; Winston Craig
- "Phytotherapy Research"; S. Gorinstein, et al.; May 2010
- "Plant Foods for Human Nutrition"; Dietary Onion Intake as Part of a Typical High Fat Diet Improves Indices of Cardiovascular Health Using the Mixed Sex Pig Model; N.K. Gabler, et al.; December 2006
- MayoClinic.com; High Cholesterol -- Lifestyle and Home Remedies; June 1, 2011
