Cholesterol Defined

Cholesterol might be the most confusing nutrition topic to the public. There's the good kind, the bad kind, the in between kind, the kind in food, the kind in the human body...you catch my drift. The truth is, as always, a little more complex than that. Although high blood cholesterol is a common and unhealthy problem in the American population, cholesterol does serve a purpose. A member of the sterol family, cholesterol is made in the body and obtained from eating animal products. It is used by the body to make bile, which is important for fat digestion. Cholesterol is also an important component in the structure of the brain and nerve cells. However, too much cholesterol is a bad thing as it contributes to the plaques that clog the arteries and lead to heart disease. Knowing your blood lipid (cholesterol, triglycerides, HDL, LDL) numbers is very important as there are dietary changes you can make to improve them and decrease your risk. If you don't know what your numbers are, I strongly recommend you get them tested.

Types of Cholesterol and Guidelines

• HDL (High-Density Lipoprotein)- Commonly known as the "good cholesterol", HDL is not technically a cholesterol, but a carrier of cholesterol in the blood. HDL carries cholesterol from the body to the liver where it will be broken down and disposed of. When looking at bloodwork, the higher the HDL number the better. HDL should be greater than 40 mg/dL.
• LDL (Low-Density Lipoprotein)- Often referred to as the "bad cholesterol", LDL is also a cholesterol carrier molecule. LDL carries cholesterol and lipids from the liver to other body tissues. Elevated LDL levels are associated with an increased risk of heart disease, hence the nickname of "bad". Blood LDL levels should be less than 100 mg/dL.
• Total Cholesterol- typically when people talk about their cholesterol levels they are referring to their total cholesterol level, which is a combination of HDL and LDL. Total cholesterol levels should be less than 200 mg/dL.
• Triglycerides- These are the primary form of fat found in foods and the human body. Blood triglyceride levels are typically measured along with cholesterol as elevated trigylceride levels are associated with increased risk of heart disease. Optimal blood triglyceride levels are less than 150 mg/dL.

Dietary Factors
Although blood cholesterol levels are thought to be somewhat genetic there are dietary modifications that can be made to improve your numbers.

• Keep total dietary fat moderate. Only 20-30% of your total daily calories should come from fat. If you are trying to lower your cholesterol that number should be closer to 20. Don't know how to calculate that? Use this example: If you consume 2,000 calories a day then 20% of 2,000 is 400 calories. There are 9 calories in every 1 gram of fat, so take 400/9 to get a daily total of 44.4 grams of fat.
• Decrease saturated fat intake- Saturated fats from animal products such as beef, butter, lard, cheese, and whole fat dairy products raise LDL, and possibly HDL cholesterol, contributing to elevated total cholesterol and increased heart disease risk. Of your total daily fat budget, only 1/3 should come from saturated fat.
• Eliminate trans fat. Trans fat is found minimally in nature and mostly in processed foods. Anytime an ingredient list includes "hydrogenated oils" you can be sure the product contains trans fat. Trans fat does a double whammy to your blood lipids as it not only raises LDL but also lowers HDL! You should consume no more than 2 grams of trans fat a day.
• Focus on unsaturated fat. Most of your daily fat should come from unsaturated sources such as nuts and seeds, avocado, fish, flaxseed, soy, and vegetable oils such as olive and canola. Since you need to keep your total fat in check, it is best to substitute unsaturated fats for saturated fats instead of adding them on top of your current diet.
• Keep your dietary cholesterol in line. Although your dietary fat intake effects your blood cholesterol more than you your dietary cholesterol intake, you still want to keep it moderate. Aim for no more than 300 mg of dietary cholesterol per day.
• Increase soluble fiber intake. Soluble fibers actually help lower your cholesterol so focus on eating lots of fresh fruits and vegetables, oats, legumes, and barley. Total daily fiber (soluble and insoluble) should be at least 25 grams.
• Increase omega-3 fatty acid intake. There is some research to show that omega-3 fats have a positive influence on cholesterol and triglycerides. Aim to have a fatty fish meal, such as salmon, 2 to 3 times a week. If you do not eat fish, flax is an acceptable vegetarian source.
• Increase plant sterol intake. These cholesterol-like molecules compete with cholesterol for absorption and help to lower LDL levels. The current recommended intake is 2 g/day. In addition to consuming lots of fruits and vegetables, the use of margarine spreads with added plant sterols such as Benechol or Take Control may be beneficial.

Healthy Fats, Healthy People

Fat was the culprit of the American obesity epidemic in the 80s. With the guilty party identified the food industry starting pumping out fat free and low fat products left and right. Unfortunately, our waistlines kept growing. The problem was that food manufacturers added sugar to their products to make them taste good in the absence of fat. Oftentimes, the calorie level of the regular and fat free versions were near identical. Don't believe me? Check out the nutrition label on regular Wheat Thins versus reduced fat Wheat Thins next time you are at the grocery store. You only save about 20 calories! In addition, studies have shown that people tend to eat more food when they choose fat free products over the full fat version. It's the "I can have one more, it's fat free!" mentality. It turns out that fat is not the enemy it was once made out to be. It actually has several essential functions in the body including internal organ protection, nerve transmission, and absorption of fat soluble vitamins. You need it in your daily diet.

Of your total daily calories, about 20-30% should come from fat, depending on your specific goals and health. What's most important is that you choose more of the so-called heart healthy unsaturated fats instead of saturated fats. Saturated fats tend to be solids at room temperature (think butter and animal fat) and can increase your risk of heart disease, high cholesterol, and atherosclerosis when consumed in excess. Saturated fats should be limited to 10% of your total daily calories. The rest should come from unsaturated fats which tend to be liquids at room temperature (think olive and canola oil) and promote heart health. The unsaturated fats can be further divided into 2 categories: monounsaturated and polyunsaturated. Both are healthy but today I'm going to focus on some specific polyunsaturated fats- the essential fatty acids omega-3 and omega-6. Together, they are involved in the regulation of many processes in the body including blood pressure, blood clot formation, blood lipids, the immune response and the inflammation response to stress and infection. They are called essential because they are vital to these processes, yet they cannot be produced by the body so must be consumed in your diet.

You've probably heard a lot about the health benefits of eating fish. Fish provides the essential fatty acid omega-3, also known as alpha-linolenic acid. Although you need to consume both of the essential fatty acids on a daily basis most Americans get too much omega-6 and not enough omega-3 so I will further narrow my fat focus to omega-3. Males should consume 1.6g/day and women should consume 1.1g/day of omega-3. Focus on meeting your daily omega-3 needs from food. Try to eat a variety of fish 2-3 times per week. If you don't like fish, incorporate flaxseed oil or omega-3 fortified products (such as eggs) into your diet. If you are having a hard time meeting these needs with food alone a supplement may be beneficial.

The following is a list of the amount (in grams) of omega-3 fat in a 4 oz serving:
Pacific herring -2.4
Mackerel -2.1
Atlantic salmon -2.1
Canned pink salmon-1.9
Trout-1.1
Canned white tuna-0.8
Canned light tuna-0.3
Canned sardines-0.7
Shrimp-0.4
Flaxseed oil (14 g)-8.4
Fish oil capsule (2)-7.2

Bottom Line: Most of the fat in your diet should come from unsaturated fats such as canola and olive oil, nuts, seeds, avocado, flaxseed, soy, and fish. Aim to consume fish 2-3 times per week.

Getting more fish in your diet doesn't have to involve cracking open another can of tuna! Below is an awesome fish recipe.

Salmon with Lime-Ginger Dressing
2/3 cup fresh lime juice (about 5 limes)
1/2 cup honey
1/2 tsp grated peeled fresh ginger
4-6 oz skinned salmon fillets (about 1 inch thick)
cooking spray
1 sliced peeled mango
1 sliced peeled avocado
8 cups gourmet salad greens

Combine the lime juice, honey, and ginger in a small bowl, reserving 3/4 cup juice mixture for dressing. Place the salmon fillets on a broiler pan coated with cooking spray. Baste fillets with remaining juice mixture. Broil 4 minutes on each side or until desired degree of doneness, basting once after turning.
Divide salad greens among 4 plates. Arrange salmon, mango, and avocado on top of greens. Drizzle with reserved dressing.

Makes 4 servings (1 serving= 2 cups greens, 1 salmon fillet, 1/4 mango, 1/4 avocaco, 3 TBSP dressing)