Triglycerides

Triglycerides play an important role in metabolism as energy sources and transporters of dietary fat. They contain twice as much energy as carbohydrates and proteins. In the intestine, triglycerides are split into glycerol and fatty acids, which are then absorbed into the cells lining the intestines, packaged together with cholesterol and proteins, excreted the lymph system and transported to the large vessels near the heart before being mixed into the blood. From there, triglycerides can be released to be used as a source of energy.

Fat and liver cells can synthesize and store triglycerides. When the body requires fatty acids as an energy source, the hormone glucagon sends a message to release free fatty acids.

As the brain can not utilize fatty acids as an energy source, the glycerol component of triglycerides can be converted into glucose for brain fuel. Fat cells may also be broken down for that reason, if the brain's needs ever outweigh the body's.

Cholesterol

Cholesterol is a waxy, fat-like compound that belongs to a class of molecules called steroids. It's found in many foods, in your bloodstream and in all your body's cells. If you had a handful of cholesterol, it might feel like a soft, melted candle. Cholesterol is essential for:

• Formation and maintenance of cell membranes (helps the cell to resist changes in temperature and protects and insulates nerve fibers)
  
• Formation of sex hormones (progesterone, testosterone, estradiol, cortisol)
  
• Production of bile salts, which help to digest food
  
• Conversion into vitamin D in the skin when exposed to sunlight.

About 85% of our blood cholesterol is produced by the body. The remaining 15% comes from our diet (meat, chicken, fish, eggs and dairy, etc). The cholesterol already in the blood can be increased by what we eat (foods containing high cholesterol and saturated fat). Higher cholesterol levels can cause a build up of plaque in arteries (which can break off and get trapped in other areas, causing blockage of blood vessels).

The average American man eats about 360 milligrams of cholesterol a day; the average woman eats between 220 and 260 milligrams daily. So how are we doing? The American Heart Association recommends that we limit our average daily cholesterol intake to less than 300 milligrams. Obviously, people with high levels of cholesterol in the blood should take in even less.

LDL’s transport cholesterol to peripheral tissues. High levels of small density LDL’s are associated with coronary artery disease (which is why LDL’s are known as bad cholesterol).



HDL’s(good cholesterol) transport cholesterol back to the liver for excretion. Women typically have higher levels of HDL’s than men do.

• Low HDL cholesterol (less than 40 mg/dL for men, less than 50 mg/dL for women) puts you at higher risk for heart disease.
• In the average man, HDL cholesterol levels range from 40 to 50 mg/dL.
• In the average woman, they range from 50 to 60 mg/dL.
• An HDL cholesterol of 60 mg/dL or higher gives some protection against heart disease.

Lifestyle factor’s that can affect cholesterol levels:

• Smoking can lower HDL’s by as much as 15%
• Exercise can increase HDL’s and lower LDL’s
• Exercise can also help reduce weight, which in turn can reduce overall cholesterol
• A glass of alcohol a day can raise HDL’s (however, it may affect sleep patterns and habitual alcohol consumption can have other negative health consequences - see blog on sleep)

Comments:
Since cholesterol is the precursor to hormones, low cholesterol levels could be an indicator of lower hormone levels.

Low cholesterol levels may also be associated with depression and anxiety. Some scientists believe that very low cholesterol may reduce serotonin levels in the brain. Reference: Mayo Clinic cardiologist Gerald Gau, M.D.

MY CURRENT LEVELS

• Total Cholesterol - 159 (not terribly low - previous testing showed 133 which is getting pretty low)
• HDL - 46mg (normal is between 50-60 for women – normal for men is 40-50)
• LDL = 96