Low blood levels of HDL-cholesterol (high density lipoprotein-cholesterol) and high levels of LDL-cholesterol (low density lipoprotein-cholesterol) are risk factors for cardiovascular disease. LDL-cholesterol is most easily oxidized and may be a cause of atherosclerosis. Therapeutic approaches to atherosclerosis include finding products which prevent LDL oxidation.
Fermented milk and cultured products with dairy have cholesterol lowering effects. The present study was done to determine the ability of lactobacillus to lower cholesterol and to prevent lipoprotein oxidation. Several lactobacillus bacteria species were screened for their antioxidant effects. Oxidation was tested by standard chemical tests.
In this study rats were fed either normal or oxidized soy oil and skim milk, 5% freeze-dried culture or fermented milk using Lactobacillus casei for 90 days. Their blood was analyzed for cholesterol and oxidation products. The group fed skim milk was compared with those fed fermented milk or the group fed culture with Lactobacillus casei and dairy.
The testing showed that rats that were fed only oxidized oil and skim milk had reduced blood levels of vitamin E as compared to rats fed fermented milk or culture. (Oxidation of LDL seems to cause a depletion of vitamin E blood levels.) The animals fed oxidized oil with fermented milk or culture had lower LDL-cholesterol levels. Lactobacillus (L.) casei 19 fed rats showed maximal anti-oxidative activity. Others, such as L. acidophilus, L. casei 63, L. helveticus and L. delbrueckii bulgaricus showed good anti-oxidant activity of a lesser degree.
CONCLUSION: The authors concluded that Lactobacillus (L.) casei has cholesterol lowering and antioxidant effects when used in the diet or as supplements. L. casei may reduce atherosclerosis and fermented milk products have health benefits.
(Tea, wine and vegetables inhibit LDL oxidation, too.)