Everyone knows that high-density cholesterol is good cholesterol, and low-density cholesterol is bad cholesterol. These two indicators are the “gold standard” for judging whether blood circulation is healthy in a physical examination. Too much “bad cholesterol” can easily lead to atherosclerosis. However, few people know that, compared with larger cholesterol particles, those smaller bad cholesterol particles are more likely to cause plaque rupture and even sudden death.
Generally speaking, the atherosclerotic plaques in human blood vessels are formed by the accumulation of low-density lipoprotein cholesterol particles, and low-density cholesterol particles are divided into large, medium and small. Among them, small and dense particles account for the total low density. Lipoprotein cholesterol accounts for 40%, medium size accounts for 30%, and larger ones account for 30%. The part where atherosclerotic plaques in humans grow is where cholesterol attaches to the walls of blood vessels, and small particles of low-density lipoprotein cholesterol are more likely to penetrate the inner membrane to form deposits. In addition, small particles of low-density lipoprotein cholesterol also have better adhesion to the blood vessel wall under the intima, and are less likely to be washed away with the flow of blood, so it is easier to promote the occurrence of atherosclerosis.
Therefore, the current clinical test indicators are only the concentration of bad cholesterol in the blood, which cannot accurately reflect the risk of clogged blood vessels. The bad cholesterol particle index, LDL Particle Testing (LDL-P), which has been used clinically, can predict the risk of cardiovascular disease more accurately. The concept of bad cholesterol particles is also widely used in scientific research.
For example, avocados have been shown to reduce bad cholesterol levels and help reduce the risk of cardiovascular disease. But, are the cholesterol lowered by avocado large particles or small particles? Recently, a study published by researchers from the University of Pennsylvania in the United States showed that for people who are overweight and obese, eating an avocado a day can help reduce the level of small particles of “bad cholesterol”, that is, oxidized small and dense low-density lipids. Protein particles (One avocado a day helps lower badcholesterol for heart healthy benefits. ScienceDaily, 28 October 2019).
The researchers pointed out that the small and dense oxidized low-density lipoprotein particles are very unfavorable to cardiovascular health and play an important role in the formation of arterial plaque. The study included 45 men and women aged 21-70, all of whom were overweight or obese, and had elevated levels of bad cholesterol. The study randomly provided 3 diets, each for 5 weeks, including 1 low-fat diet and 2 medium-fat diets. The avocado diet included one avocado per day, and the other medium-fat diet used the fatty acids contained in avocados. match. The results show that the avocado is mainly to reduce the small and dense oxidized low-density lipoprotein particles in the blood.
Because the fatty acids contained in avocado are added to the medium-fat diet, it is likely that other biologically active ingredients such as plant sterols play a role. Phytosterols are components in plants that have a similar structure to cholesterol. They can be embedded in cholesterol particles to change the shape and size of the particles, and form “micelles” with excess cholesterol to be excreted from the body and “dissolve” cholesterol plaques on blood vessel walls. Therefore, eating more nuts and vegetables to increase the intake of phytosterols is an effective measure to reduce cardiovascular diseases.
