Sunday, September 28, 2008

Cholesterol Confusion

Everyone knows what cholesterol is now - that stuff that clogs arteries and causes heart attacks, right?


When you get a blood test for "cholesterol", what they are measuring is not the chemical cholesterol directly, but instead is the total amount of certain lipoproteins that just happen to contain some cholesterol. It's a bit of a misnomer - sort of like calling a car an engine. Let's measure the weight of all those engines on the road by totaling the weight of all the cars on the road. What's worse, there are many other vehicles on the road that have engines but are not cars, like trucks and buses. Does it make sense to total the weight of just cars as an indication of the weight of engines on the road?

There is a chemical called cholesterol and it's an essential part of every cell membrane. It's a precursor to several important hormones and to vitamin D. It's considered both a sterol and a lipid, but not a fat. All fats are lipids, but not all lipids are fats. Cholesterol and fats are not soluble in water, but are needed by our cells. In order to transport cholesterol and fats through our blood, which is largely water, our body bundles them into packages of protein, fat,and cholesterol that can be carried in the blood. These packages are lipoproteins.

There are several kinds of lipoproteins the body uses for different purposes. They are classified by their density, which also roughly corresponds to their size. The largest and least dense are chylomicrons, followed by very low density lipoprotein (VLDL). Both of these contain cholesterol but are not included in total "cholesterol" blood tests. Next are low density lipoproteins (LDL), intermediate density lipoproteins (IDL), and high density lipoproteins (HDL).

In blood tests, the VLDL is called "triglycerides", even though all lipoproteins contain triglycerides (more confusion?) and "total cholesterol" is the total of LDL, some IDL, and HDL.

So how do cholesterol and lipoproteins relate to heart disease?

True cholesterol does not really appear to be a player in heart disease. It is actually very important for good health. However, glycated proteins and fats as well as oxidized fats, all of which can be incorporated into lipoproteins, do appear to play a role. Glycation occurs when a sugar molecule, such as fructose or glucose, binds to a protein or fat and oxidized fats are generally polyunsaturated fats that have been oxidized into peroxides. Some types of glycated proteins and all fat peroxides can cause a variety of problems and are implicated in both heart disease and cancer.

For optimal health, and thus avoidance of heart disease and cancer, we should be striving to reduce our load of glycated proteins and oxidized fats. Elevated blood sugar and triglyceride levels are correlated with elevated blood levels of glycated protein. So, obviously, keeping blood sugar and triglyceride levels normalized is ideal. Eat starches with fat and protein to minimize blood sugar spikes after meals or snacks. Don't eat foods with added refined sugar and don't eat too much fruit. Low-carb diets and/or excercise tend to normalize blood sugar and triglycerides.
The fats most prone to oxidation are polyunsaturated fats. Large amounts of dietary polyunsaturated fat are new to the human diet. Up until the last couple hundred years, the typical amount of dietary polyunsaturated fat was around five percent of dietary calories or less. Only recently has the amount of polyunsaturated fat been increasing dramatically in the human diet as cheap vegetable oils have displaced healthier animal fats in commercial food products. Keeping dietary polyunsaturated fats under four percent of total calories is ideal. That means avoiding most processed foods like sauces, dressings, baked goods, and most cooking oils, and eating only small amounts of nuts. Most commercial sauces and dressings are loaded with soybean oil or other oils high in polyunsaturated fat. Most commercial cooking oils are also high in polyunsaturated fat and sometimes trans-fat (made from hydrogenated polyunsaturated fat). That means avoid most commercial fried and baked foods.

Sunday, September 14, 2008

WAP Diet

No, it's not another fad diet for losing weight!

It's really a philosophy for healthy eating that's been around for thousands of years and was put into perspective about 70 years ago by the work of Weston A. Price (WAP). The idea is to eat foods that kept our ancestors healthy and to avoid highly processed and refined foods that are low in nutrients and high in harmful additives. Actually, many people do lose weight using this approach to eating, but the main goal is getting good nutrition for optimal health. Normalizing weight is a fringe benefit :)

Not all of the foods that our ancestors ate were equally healthy. Some foods confer greater health than others. That's what Weston Price studied in the 1920's and 1930's when he traveled around the world to document the native foods that people ate and their health. His conclusion was that the healthiest native diets included animal seafoods, organ meats, and/or dairy in their diet. These are the foods that have provided optimal nutrition for thousands of years. He found that when people abandoned the healthy diet of their ancestors for a more modern diet of refined flour and sugar and highly processed foods, their health suffered greatly.

Today we see a massive shift to highly processed foods in much of the world and a corresponding rise in poor health. Rates of obesity are increasing rapidly as people follow sadly misguided conventional dietary and health advice and are confused and misled by advertising for manufactured fake foods. When they get sick, they are given expensive drugs that often cause more health problems than they solve. It's time to get back to the foods that kept people healthy for thousands of years and shun the modern manufactured fake foods.

The Weston A. Price Foundation (WAPF) has been teaching the about the WAP approach to eating for about 10 years now and is a good source for health and diet information. My experience is that each of us has to discover which ancestral foods are best for us by trial and error. Not all traditional foods are best for everyone. Try them out and find the ones that work best for your health. Here's a WAPF video that discusses Price's teachings:

Some people have food sensitivities to even some traditional foods that others are able to tolerate. Read here for more information about food sensitivities. That's why it's important to find the traditional foods that work best for your own health.