"Those pamphlets adorning your doctor's waiting room may portray LDL as a kind of lone gunman taking a bead on your heart, but they hide a basic fact of science: "Bad cholesterol" is at best a poor shorthand for four major types of independently behaving LDL, each with its own implications for heart disease. We ignore the distinctions at our peril.
Some of these forms of LDL are relatively safe and some are dangerous, and treating them all as one and the same -- the way we do every time we pay our clinic for a three-part lipid panel that simplistically says "LDL: 125" -- is telling us little about the LDL cholesterol that matters, all the while sending health costs through the roof. We may be medicating many people who have no clear need for medication, using drugs that don't target the right particles, and replacing foods that are benign with foods that are anything but.
So in the heart-disease world, we've been stalking the devil we know instead of the devils we don't know. But we need to get to know them if we hope to dodge the number one killer of men.
Some of these forms of LDL are relatively safe and some are dangerous, and treating them all as one and the same -- the way we do every time we pay our clinic for a three-part lipid panel that simplistically says "LDL: 125" -- is telling us little about the LDL cholesterol that matters, all the while sending health costs through the roof. We may be medicating many people who have no clear need for medication, using drugs that don't target the right particles, and replacing foods that are benign with foods that are anything but.
So in the heart-disease world, we've been stalking the devil we know instead of the devils we don't know. But we need to get to know them if we hope to dodge the number one killer of men.
LDL COMES IN FOUR BASIC FORMS: a big, fluffy form known as large LDL, and three increasingly dense forms known as medium, small, and very small LDL. A diet high insaturated fat mainly boosts the numbers of large-LDL particles, while a low-fat diet high in carbohydrates propagates the smaller forms. The big, fluffy particles are largely benign, while the small, dense versions keep lipid-science researchers awake at night.
But here's the problem: The typical LDL test doesn't distinguish between large and small LDL particles -- it can't even spot the difference. And people can have mostly large LDL or mostly small LDL in their overall LDL, depending upon a host of genetic, lifestyle, and environmental factors. Your own personal mix may make all the difference between living to a heart-healthy old age and becoming a Monday-morning casualty at your desk.
Dr. Krauss and collaborators from Harvard and Malmo, Sweden, have helped identify what influences the difference. Working with blood samples from 4,600 healthy Swedish men and women, they used ion mobility analysis to count 11 forms of cholesterol subparticles for each person, and then ran the data through a complex statistical sorting program. After looking for relationships correlating with the 8 percent of people who went on to develop cardiovascular disease, they found three scenarios that predicted it, from the most powerful predictor to the least:
1. High levels of smaller and medium LDL combined with low HDL (a dreaded diabetes-linked syndrome Dr. Krauss had previously called atherogenic lipoprotein phenotype, or pattern B)
2. Low HDL levels
3. High total LDL levels
According to Dr. Krauss, the three risk factors appear to represent three separate processes that put your cardiovascular health at risk. For men, the first two scenarios are more predictive of heart disease, but the third -- high total LDL -- was only marginally predictive of heart disease in men. Nowhere to be seen, of course, is the "total cholesterol" number doctors have been bashing us over the head with for decades. Turns out that number is not as useful a predictor for individuals. "LDL cholesterol is used as a marker for heart-disease risk," Dr. Krauss explains. "It's not a perfect marker, and the particle story is part of the reason for that."
In other words, when you tease apart the subsets of LDL that are preferentially involved in heart disease, total LDL is a less reliable bio-marker. It's like the sniffles that could signal allergies, or the onset of swine flu, or nothing at all. This ambiguity works both ways. Just because you have less of the symptom (statin users take note) doesn't mean you'll have less of the disease. A drop in your total LDL cholesterol might mean nothing at all. A higher LDL cholesterol reading, for that matter, could simply mean you are a healthy person who has learned how to build an amazing sauce out of wine, garlic, shallots, butter, and heavy cream."
But here's the problem: The typical LDL test doesn't distinguish between large and small LDL particles -- it can't even spot the difference. And people can have mostly large LDL or mostly small LDL in their overall LDL, depending upon a host of genetic, lifestyle, and environmental factors. Your own personal mix may make all the difference between living to a heart-healthy old age and becoming a Monday-morning casualty at your desk.
Dr. Krauss and collaborators from Harvard and Malmo, Sweden, have helped identify what influences the difference. Working with blood samples from 4,600 healthy Swedish men and women, they used ion mobility analysis to count 11 forms of cholesterol subparticles for each person, and then ran the data through a complex statistical sorting program. After looking for relationships correlating with the 8 percent of people who went on to develop cardiovascular disease, they found three scenarios that predicted it, from the most powerful predictor to the least:
1. High levels of smaller and medium LDL combined with low HDL (a dreaded diabetes-linked syndrome Dr. Krauss had previously called atherogenic lipoprotein phenotype, or pattern B)
2. Low HDL levels
3. High total LDL levels
According to Dr. Krauss, the three risk factors appear to represent three separate processes that put your cardiovascular health at risk. For men, the first two scenarios are more predictive of heart disease, but the third -- high total LDL -- was only marginally predictive of heart disease in men. Nowhere to be seen, of course, is the "total cholesterol" number doctors have been bashing us over the head with for decades. Turns out that number is not as useful a predictor for individuals. "LDL cholesterol is used as a marker for heart-disease risk," Dr. Krauss explains. "It's not a perfect marker, and the particle story is part of the reason for that."
In other words, when you tease apart the subsets of LDL that are preferentially involved in heart disease, total LDL is a less reliable bio-marker. It's like the sniffles that could signal allergies, or the onset of swine flu, or nothing at all. This ambiguity works both ways. Just because you have less of the symptom (statin users take note) doesn't mean you'll have less of the disease. A drop in your total LDL cholesterol might mean nothing at all. A higher LDL cholesterol reading, for that matter, could simply mean you are a healthy person who has learned how to build an amazing sauce out of wine, garlic, shallots, butter, and heavy cream."
http://www.menshealth.com/men/health/heart-disease/understanding-cholesterol-and-heart-disease/article/34cf5983f7a75210vgnvcm10000030281eac/6#
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