New research suggests that consuming an avocado daily can help keep unhealthy cholesterol at bay. The term ‘bad cholesterol’ includes both oxidized low-density lipoprotein (LDL) as well as small, dense LDL particles.

They conducted a randomized, controlled feeding study which revealed that eating an avocado every day lowers one’s bad cholesterol levels among adults with obesity or overweight. The lead author Penny Kris-Etherton opines that small, dense LDL particles are particularly harmful since they promote plaque buildup in the arteries.

"We were able to show that when people incorporated one avocado a day into their diet, they had fewer small, dense LDL particles than before the diet," he said. People should consider including avocados to their diet in a healthy way such as on a whole-wheat toast or as a veggie dip, he added.

The study specifically found that avocados helped in lowering LDL particles which had been oxidized. And just like the way oxygen can damage food, oxidation is also likely to have bad effects on your health. The authors opine that a lot of research points towards oxidation being the cause of various health conditions like cancer and heart diseases. The oxidation of LDL particles can cause a chain reaction that can promote atherosclerosis (the building up of plaque in the walls of your arteries). Since oxidation can be bad for your body, if you can protect yourselves by consuming certain foods, it could indeed be very beneficial.

Although older studies have found that avocados could help lower LDL cholesterol levels, this study makes it clear whether avocados could also help lower oxidized LDL particles.

The study included 45 adults who were either obese or overweight and were followed for a two-week “run-in” diet. They were then asked to follow three different treatment diets in a randomized order for five weeks. Those who followed the moderate-fat diet without avocados were given extra healthy fats. After five weeks, they found that the participants who were on the avocado diet had significantly lower levels of oxidized LDL cholesterol before the study began. They also reported higher levels of Lutein (an antioxidant) among the avocado consumers. The researchers specifically found a reduction in oxidized small, dense LDL cholesterol particles.

"When you think about bad cholesterol, it comes packaged in LDL particles, which vary in size," Kris-Etherton said. "All LDL is bad, but small, dense LDL is particularly bad. A key finding was that people on the avocado diet had fewer oxidized LDL particles."

The research concluded that since a moderate-fat diet without avocados (which contained the same monounsaturated fatty acids present in avocados), it is likely that the fruit specifically possesses some kind of additional bioactive which could have contributed to the benefits of the avocado diet.

Although the findings of the study are promising, the researchers feel that further research might be required. Also since nutrition research on avocados is a relatively new area of research, they feel that they are at the tip of the iceberg for learning about their health benefits.

"Avocados are really high in healthy fats, carotenoids -- which are important for eye health -- and other nutrients. They are such a nutrient-dense package, and I think we're just beginning to learn about how they can improve health," Kris-Etherton said.