So in this note I wanted to discuss the role of fats and cholesterol. When most people hear “fat” or “cholesterol” they cringe away from it because it’s usually associated with bad things. But cholesterol and the right types of fats have a very beneficial effect on the body.
First off, cholesterol is not necessarily a bad thing. People often think it is because it causes so many diseases but that’s only when you eat too much of it. Really, cholesterol isn’t even needed in the diet. Your body makes all of the cholesterol it needs. It is used to make cell membranes in the body as well as bile (which is made in the liver, stored in the gall bladder, and used in the digestion of fats) and your steroid sex hormones (which are the female/male hormones).
As mentioned above, cholesterol becomes a problem when too much of it is consumed. LDL (Low density lipoprotein) isn’t a type of cholesterol but a type of transporter that carries cholesterol. It carries cholesterol from the liver and deposits it in cells. It becomes a problem when there is too much cholesterol because it then spills out of the cells and is deposited in the arteries where it contributes to atherosclerosis (plaque build up) and arteriosclerosis (hardening of the arteries).
Both of these conditions can lead to heart disease, hypertension, myocardial infarction (heart attack), and stroke. A heart attack occurs when blood flow to the heart is decreased due to a blocked artery leading to the heart. A stroke occurs when blood flow to the brain is decreased due to a blocked artery in the brain. To decrease your risk of these conditions you can decrease your LDL cholesterol levels by reducing your saturated fat intake, increasing your monounsaturated fat intake, and increasing soluble fiber intake.
HDL (High density lipoprotein) is also a cholesterol transporter but this one takes cholesterol out of your arteries and back to the liver where it is metabolized and rid of. To increase your HDL cholesterol levels you can exercise. Consumption of omega 3 fatty acids can also increase HDL levels as well as quitting smoking.
Cholesterol is only found in animal products so continued consumption of these products will also contribute to your cholesterol levels.
It is important to know what type of LDL and HDL levels you should be aiming for so below, they are listed.
LDL cholesterol: less than or equal to 200 mg/dL
HDL cholesterol: greater than or equal to 60 mg/dL
Total cholesterol: less than or equal to 200 mg/dL
Triglycerides (the main storage form of fats in the body): less than or equal to 150 mg/dL
On to fats. When I said “the right type of fats” earlier, I meant unsaturated fats. This is an umbrella term for monounsaturated fats and polyunsaturated fats. Monounsaturated fats are found in foods like avocados, peanut oil, olive oil, and canola oil. They lower your LDL cholesterol levels and leave your HDL cholesterol levels alone. When choosing foods that are high in unsaturated fats, you want to choose ones that have more unsaturated fats because these ones leave your HDL alone. This may sound like a bad thing but polyunsaturated fats lower your LDL cholesterol and they also lower your HDL cholesterol. You don’t want your HDL cholesterol to be low because it’s what moves cholesterol out of your arteries. Polyunsaturated fats are found in foods like sunflower oil, safflower oil, fatty fish, and flax seed. Omega 3 fatty acids are a type of polyunsaturated fat that are even better than monounsaturated fats because they not only lower your LDL, but they lower your triglyceride levels, raise your HDL levels, and make your blood less sticky. These fats are found in fatty fish like salmon, tuna, and herring.
Now the bad fats that you want to try to stay away from are saturated fats and trans fats. Both of these raise your LDL levels and lower your HDL levels. Trans fats are especially bad because consumption of the tiniest amount of them greatly increases your risk for all sorts of diseases. The bad thing about trans fats is that many food labels claim to be trans fat free yet many products still contain trans fats. If the ingredients list contains partially hydrogenated (any type of oil) or hydrogenated (any type of oil), then that means that product contains trans fats. If it claims to be trans fat free and it contains one of those types of oils, then it can have up to 0.5 g of trans fat per serving. The important thing to note here is per serving. Many people do not stop at one serving so it is really important to note serving sizes when consuming foods.
Another issue I would like to address is the debate over butter and margarine. People often wonder which is better and to be honest, neither one is really better than the other. Most butters contain high amounts of saturated fats while margarine usually contains hydrogenated oils (aka trans fats). The best thing to do here is to go with liquid sprays which contain smaller amounts of saturated and trans fats. The best thing to do is to cook with oils such as canola oil or olive oil.
One last note, total fat (these means saturated fat, monounsaturated fat, and polyunsaturated fat) should make up about 25 – 35% of your calorie intake. Of this, the saturated fat should only make up about 10%. Trans fats should ideally make up 0% of your calorie intake so try to consume as little as possible.
Below is a quick review of the fats that have been mentioned:
Polyunsaturated fats: lower LDL, raise HDL
Monounsaturated fats: lower LDL, leave HDL alone
Omega 3 fatty acids: lower LDL, lower triglyecerides, raise HDL, make the blood less sticky
Saturated fats: raise LDL, lower HDL
Trans fats: raise LDL, lower HDL
- The Keys to Cutting Cholesterol (everydayhealth.com)
- The fats of life (f00dventures.wordpress.com)
- Tips for Lowering Cholesterol (goldenrule.com)
- Avocados, Good Fats & Heart Health (avocadocentral.com)
- Long-Term effects of a Ketogenic diet in obese patients (alexpascoe.com)
- hdl patient handout (jaysonmaxfield.typepad.com)
- The Skinny on Fat (theabeni.wordpress.com)
- Understanding Cholesterol (emberbranch.wordpress.com)
- How to have a healthy heart for life (foxnews.com)