Some facts about cholesterol so you don’t freak out next time you eat egg yolks, a ribeye or some bacon.
- Cholesterol is an organic molecule essential for life—we consume it, we can make it, we can store it and we can get rid of it.
- No cholesterol means no life.
- Cholesterol comes in 2 forms: unesterified (free) cholesterol and esterified.
- Therefore, not all cholesterol we eat is absorbed because some is in the esterified form (it needs to be de-esterified to be absorbed in your gut).
- Most of the cholesterol in our body is made by our body (endogenous production).
- Consumption of cholesterol, that is dietary cholesterol, has very little impact on cholesterol levels in our bodies. Think otherwise? Read this then.
- Having high total cholesterol (TC) does not mean you have cardiovascular disease.
- Cholesterol and triglycerides (i.e. fats) must be carried in your blood by lipoproteins—these are like little cargo ships that shuttle cholesterol and triglycerides around your body.
- Lipoproteins are: VLDL, IDL, LDL, HDL
- Proteins exists within lipoproteins they help classify them: apoB are found in VLDL, IDL, LDL; and apoA-1 are found in HDL.
- Classifying LDL cholesterol as “bad” and HDL cholesterol as “good” is all wrong. These lipoproteins work synergistically to transport lipids efficiently in the body—neither one being “good” or “bad.”
- The most significant part of plaque build-up, that is “clogging” arteries, is the penetration of blood vessel walls and retention within the walls by apoB lipoprotein LDL. Inflammation of the blood vessel walls makes things worse.
- Having high LDL cholesterol (LDL-C) does not mean you will have clogged arteries. You must measure the LDL particle (LDL-P) size.
- Meausre LPL-P by measuring apoB or LDL-P NMR (nuclear magnetic resonance).
- Lower LDL-P number will prevent/stop plaque build up.
Hotamisligil & Erbay, 2008.
Confused? Yeah, sorry. It looks confusing but really this figure is very interesting because we are taking a snap shot of the inside of a cell, and looking at all the signalling pathways involved. Notice the top, there is glucose (gold ball), amino acids, cholesterol (green balls) and off to the left are fatty acids (blue balls). These are nutrients you obtain from you diet and each one has an important role on your cells. In our case we are looking at the inside of the cell at what is called the endoplasmic reticulum (ER). This little guy responds to nutrient-associated signals—from insulin, fatty acids, glucose, and free cholesterol (as I just listed). What actually happens is another protein—called the unfolded-protein response (UPR)—is induced in response to an ER that is “stressed” leading to a hold cohort of inflammatory responses. A stressed ER can result in response to high glucose levels—or hyperglycemia. Prolonged levels of hyperglycemia (elevated glucose) lead to the pathway shown above. Your cell’s UPR protein reacts to a “stressed ER.” The now stressed ER from excess glucose turns on a whole bunch of pathways that lead to altered metabolic responses, a term used to describe the dysfunction of metabolism and in our case this metabolism occurs that the cellular level.
I don’t expect you to understand the figure, I am showing you this because you can see the complicated mechanism involved and the result is metabolic dysfunction and inflammation—two processes associated with dyslipidemia and obesity. This just goes to show the impact nutrients have at the cellular level, and the degree as to which that can stimulate harmful pathways. I must note that metabolic dysfunction and inflammation as seen above usually only occurs after chronic ill nutrition, that is a diet lacking in essential nutrients but one that contains high levels of glucose, and fat.
The take away message: the foods you eat every day have a direct effect on your cells, and your cells can respond in a positive or negative manner—I hope its the former.
Hotamisligil GS & Erbay E. Nutrient sensing and inflammation in metabolic diseases. Nat Rev Immunol. 2008 December; 8(12): 923.
Never thought you’d hear those two words in the same sentence would you? Well, if you did not know chocolate does have its health benefits. Dark chocolate with a coca content of around 60% is what you want to buy to find any health benefits from chocolate.
Dark chocolate contains a saturated fat called stearic acid, which is believed to be non-atherogenic—that is it does not cause atherosclerosis, or build up of plaque in your arteries, and one of the main culprits of heart disease. Dark chocolate consumption has been shown to improve:
- blood pressure
- insulin sensitivity
- blood lipid levels
- cell function
- antioxidant capacity
Now, me telling you chocolate is okay does not mean you can scarf down a tub of chocolate—no, no, no! I know you have probably heard this word many times when it comes to eating, but MODERATION is important. Interestingly enough, chocolate is a perfect example of the principle that healthy eating should be obtained not by avoiding categories of foods, but making well-informed, nutritious choices within any given food category. Now, I like to enjoy dark chocolate from time to time, and while chocolate is not on the Paleo diet I use it as a reward tool. I’ll share a little eating secret with you: I like to eat dark chocolate covered almonds, or pecans. Great way to satisfy my sweet tooth, while also supplying my body with some good fats.
Compared to its cousin, milk chocolate, the saturated fat in dark chocolate is thought to have neutral affects on cholesterol levels (mainly LDL-cholesterol= “bad” cholesterol). Another interesting property of dark chocolate is its antioxidant capacity, which is thought to react better with free radicals (products of oxidative stress) than some fruits.
Limit your dark chocolate intake because it still is comprised of fat and carbohdyrates. I would suggest eating a very small amount post-meal, that way it takes a little longer to digest and be absorbed. Remember, you can enjoy these foods—just in moderation!