Researchers previously believed it was a compound called 3-n-butylphthalide that contributed to celery’s cholesterol-lowering potential, according to an older article in Clinical and Experimental Pharmacology and Physiology. Rats with high cholesterol that were given celery extract had lowered their cholesterol levels. When the researchers isolated the 3-n-butylphthalide from the celery, it didn’t have the same cholesterol-lowering effect.
In a 2010 article in the Journal of Agriculture and Food Chemistry, researchers isolated a compound found in essential oil in mountain celery seeds called oleamide, believing that it was the ingredient that could lower blood lipids. When they created this compound in the lab, they found that it lowered LDL cholesterol and triglycerides but didn’t improve HDL cholesterol.
Combining celery with other heart-healthy foods might help reduce high cholesterol without medication, according to a 2011 study in Pharmacognosy Magazine. Celery, chicory, and barley were ground into powder and given to rats with high cholesterol. Individually, these foods lowered cholesterol, but the three combined at lower concentrations did a better job at reducing cholesterol and liver enzymes.