I have recently been concerned by the eternal question: should I eat only the top or only the bottom of a slice of pizza? Perhaps I need to invest in a new Zen calendar, just live for the moment and eat the darn pie. This of course is a sideways approach to a quick and dirty discussion of good and bad cholesterol.
What is cholesterol anyway?
Cholesterol is a fat that is in the chemical class called a sterol (kind of sounds like steroid, doesn’t it?). In fact steroids and vitamins are made from cholesterol. Cholesterol occurs naturally in plants and animals. You actually make it in your body. Cholesterol is also an essential part of your cell membranes. Cells, you might remember, are your little engines of life. You won’t go far without them. So cholesterol is a good thing in many ways. Don’t hear that very often, do you?
But, like so many other thing in life, excess leads to trouble – like the glass of red wine versus the whole bottle phenomenon. A little cholesterol goes a long way.
The trouble occurs in the handling and transport of cholesterol in your body. The liver is the main source of cholesterol production. The intestines absorb dietary cholesterol. Cholesterol is a fat, and fats don’t mix well with blood (blood is water based).
Your body makes lipoproteins which function like a soap to transport cholesterol. Soaps dissolve oil in water. For the record, Tide gets the grease out by surrounding the grease particle with molecules that dissolve in water on one end, and in oil/fat on the other end? The grease is suspended in the water in kind of a porcupine looking thing, with the soap acting like quills – how’s this for a mental picture.
These cholesterol containing particles (porcupines) are called lipoproteins, and come in several flavors, some more tasty than others. Low Density Lipoproteins (LDLs) are the bad guys. They are low density because they have more cholesterol and less protein. These have been associated with heart disease, stroke, and any manner of metabolic mayhem. They float around and are a large part of the plaques that form in arteries – the higher the LDLs, the worse the risk. LDLs are increased by dietary sources such as cheese, egg yolks, and meats like beef, pork and chicken, even shrimp. They are decreased by reducing animal fats in the diet and some medications.
HDLs are the good guys – you want lots of them. Their formal name is High Density Lipoprotein. They have a higher protein to cholesterol percentage, making them dense. They function to gather cholesterol from areas where it is problematic (in the wall of blood vessels) and transport it back centrally for disposal.
The medical community has increasingly seen HDLs as one of the most important factors in a healthy lifestyle. Many things raise the HDL levels. Among them are exercise, weight loss, moderate alcohol intake, a low-fat diet, fish oil supplements and quitting smoking. Medications can also be used to raise HDLs.
To tie up a few loose ends:
• Trans fats are not naturally occurring. They are made in factories as a food additive and used in the fast food and pastry industry. Eating trans fats is a pretty bad idea as a little of these fats really raises the bad cholesterol.
• Saturated fats (animal fats) also raise cholesterol.
• Poly unsaturated fats do the opposite – they lower cholesterol.
The answer to my original question about pizza (if you have been holding your breath) is of course a choice.
If you believe in the Atkins diet, eat the top of the pizza (protein and fat) and throw away the crust (carbohydrate). If you think cholesterol is more worrisome than weight, eat the crust and sauce (for the lycopene) and throw away the top.
My plan is to live in the moment and eat the very occasional whole pie with a glass of red wine – and exercise tomorrow.