Confusion About Cholesterol
When a friend tells you she is trying to lower her cholesterol and so has decided to avoid tilapia, a fish on the higher end of dietary cholesterol, the frequent misconceptions about cholesterol begin to surface. Can it be that a low-fat, omega-3-rich food like tilapia is to be avoided? The answer is in the vast majority of cases, no, not even for people with high cholesterol. The reason lies in the difference between dietary cholesterol and blood cholesterol. It's illustrative, then, to more closely examine the relationship between types of dietary fat, cholesterol in and outside the body, and heart health.
Just one quarter of dietary cholesterol (the amount in food shown on nutrition labels) is absorbed by the body—specifically, by the intestines. The amount of cholesterol circulating in the blood is determined by several additional factors. While the amount of cholesterol a food contains does contribute to blood cholesterol, some 75% of your blood cholesterol comes from its manufacture by the liver.
The Good, the Bad, and the Healthy
To briefly recap what we all have learned about cholesterol in the last several decades, blood cholesterol is a waxy substance that cannot move freely throughout the body. It has to be carried in the packages we know as lipoproteins. Low density lipoproteins (LDLs) carry cholesterol from the liver to the rest of the body. High levels of LDL can lead to dangerous cholesterol accumulation in the arteries. High density lipoproteins (HDLs) carry cholesterol from the body to the liver, where the cholesterol can then be removed from the blood.
The liver both manufactures and breaks down cholesterol, and the main ingredient that enables the former is saturated fat. The single biggest contributor toward high blood cholesterol is the consumption of saturated fat. This fat, of course, is found almost exclusively in animal products, including 2%-fat dairy products. The odd plants here and there that contain saturated fat—the so-called "tropical oils"—are palm oil, coconut, coconut oil, and coco butter. These foods contain zero cholesterol, but are nevertheless not considered heart-healthy due to their saturated fat content.
While too much LDL cholesterol can slowly build up in the inner walls of the arteries that feed the heart and brain, high levels of HDL cholesterol seem to protect against heart attack. In fact, low levels of HDL—less than 40 mg/dL—also increase the risk of heart disease. Some experts believe that HDL removes excess cholesterol from arterial plaque.
These two types of lipids, along with triglycerides and Lp(a) cholesterol, make up your total cholesterol count. Triglyceride is a form of fat made in the body, and tends to be lifestyle-related. Elevated triglycerides can be due to overweight or obesity, physical inactivity, cigarette smoking, and excess alcohol consumption. People with high triglycerides often have a high total cholesterol level. Lp(a) cholesterol is a genetic variation of LDL, and a high level is a significant risk factor for the premature development of fatty deposits in the arteries.
Another food source that ultimately results in higher blood cholesterol levels is trans fat (TFA), as is found in hydrogenated oils like those used in shortening, processed sweets, many baked goods, and fried fast food. Choose margarine containing no trans fat over butter (which contains saturated fat), but do note that margarine is still high in fat, and should be used in moderation. Most vegetable oils and soft or liquid margarines have less saturated and trans fat than the solid spreads have. Always check labels for the amount of saturated fat, trans fat, cholesterol, and total calories in a serving of the product, remembering that a serving is often smaller than you think. There are no labeling regulations for fast food, and it can even be advertised as cholesterol-free and cooked in vegetable oil. Eating one doughnut at breakfast (3.2 g of TFA) and a large order of French fries at lunch (6.8 g of TFA) will add 10 grams of TFA to your diet.
A Healthy Range
Aim for a total blood cholesterol of less than 200 mg/dL. At this level, have your cholesterol checked approximately every five years. At 200 to 239 mg/dL, you may have borderline-high cholesterol. This depends on whether your LDL levels are normal; the overall number may have desirably high HDL levels, meaning you have nothing to worry about. Be sure your doctor breaks down the four lipid values for you.
People who have a total cholesterol level above 240 mg/dL typically have twice the risk of coronary heart disease. Whether or not you need cholesterol-regulating medication, make lifestyle changes, including eating a heart-healthy diet, getting regular physical activity, and avoiding tobacco smoke.
An optimal LDL level is less than 100 mg/dL; to 129 mg/dL; up to 160 is considered borderline-high, and 160 to 189 is high. Above 190 is considered very high. For women, less than 50, and for men, less than 40 mg/dL of "good" cholesterol is considered too low. An HDL cholesterol of 60 mg/dL or higher gives some protection against heart disease.
Remember that people with high triglycerides often have high overall cholesterol, including low HDL and high LDL. Less than 150 mg/dL is considered normal; 200 to 499 high; and over 500 very high. Regular physical activity lowers triglycerides, and also helps remove LDL cholesterol from the blood.
Don't Ignore Dietary Cholesterol
Two decades ago, as experts unteased the relationships between dietary cholesterol, dietary saturated and trans fats, and blood cholesterol, eggs were the subject of controversial flip-flopping on the unhealthy foods list. One egg contains about 213 mg of dietary cholesterol. The daily recommended cholesterol limit is less than 300 milligrams for people with normal LDL (bad) cholesterol levels. To put this in perspective, eating one egg for breakfast, drinking two cups of coffee with one tablespoon of half-and-half each, lunching on four ounces of lean turkey breast and one tablespoon of mayonnaise, and having a 6-ounce serving of broiled steak for dinner would amount to 510 mg of dietary cholesterol in one day, nearly twice the recommended limit. Also remember that many baked goods are prepared with eggs. Those eggs count toward your daily cholesterol limit.
Studies have shown that if you increase your daily cholesterol consumption 200 to 400 mg/day (equivalent to eating one extra egg), there is no significant increase in heart attack risk. Eggs are a great source of protein and contain B12 and folate, which may even reduce the risk of heart attack.
Still, limit total fat intake to less than 35% of daily calories; limit saturated fat intake to less than 7%; eliminate or limit trans fat intake to less than 1%. The remaining fat should come from sources of monounsaturated and polyunsaturated fats. Examples of foods that contain these fats include salmon, trout, herring, avocados, olives, walnuts, and liquid vegetable oils such as soybean, corn, safflower, canola, olive, and sunflower.
If your LDL cholesterol level is 100 mg/dL or greater, limit your cholesterol intake to less than 200 milligrams a day.
Common Sources and Amounts
The foods listed here are all 100 grams or 3.5 oz, which is a fairly small portion. For example, a 6-oz piece of sockeye salmon might resemble a more typical cut as a dinner portion.
| 3.5 oz wild sockeye salmon |
175 |
61.25 mg |
8.75 g |
1.75 g |
| 3.5 oz Atlantic farmed salmon |
206 |
63 mg |
12.35 g |
2.5 g |
| 3.5 oz tilapia |
128 |
57 mg |
2.65 g |
.94 g |
| 3.5 oz deli turkey breast |
140 |
52.5 mg |
7 g |
1.75 g |
| 1 link of turkey sausage |
160 |
70 mg |
10 g |
2.5 g |
| 90% lean hamburger patty, broiled |
217 |
85 mg |
12 g |
4.6 g |
Roasted skinless chicken breast
|
165 |
85 mg |
3.6 g |
1 g |
Note that wild salmon is healthier than farmed, and that although pork weighs in as a surprisingly healthy meat option, the tilapia in the chart, which is extremely low in saturated fat, outperforms the other meat items except perhaps the skinless chicken breast. And even extra-lean ground beef does not size up at all well as a heart-healthy option.
Think Liquid: The Fat in Fish
As we can see, yes, fish contains cholesterol. Salmon is not that much lower than beef or chicken in fact. So why is fish cholesterol not ringing alarm bells? It's because fish has very little fat and almost no saturated fat. Without much saturated fat, there is almost nothing in fish for our body to convert to cholesterol. Fish oil is healthy fat; it is liquid at room temperature, which means it is not an artery-clogging type of fat. Furthermore, the fat in fish is rich in omega 3s, powerful antioxidants that contribute to heart and overall health—something you will never find in processed turkey breast.
Fish, fruits, nuts, seeds, vegetables, whole grains, and legumes: this combination of foods looks a lot like the Mediterranean diet. Last month, researchers sought to evaluate the relation between the Mediterranean diet and the development of left ventricular systolic dysfunction, both at hospitalization and with regard to a two-year prognosis of patients who have had an acute coronary syndrome.
What they found was that greater adherence to the Mediterranean diet seems to preserve left ventricular systolic function and is associated with better long-term prognosis of patients who have had a coronary event. In particular, vegetables and nuts seemed to be the foods that cut risk. Those who ate them daily or weekly enjoyed 20% lower risk of repeat heart problems within two years of their initial hospitalization compared to people who ate these foods monthly or less often.
The team looked at 1,000 patients who had suffered heart attacks or severe chest pain while at rest or with only light exertion. They rated each patient on a scale of 0 to 55 based on how closely their eating matched the Mediterranean ideal. Patients with the most Mediterranean-style diets were at 31% lower risk of suffering another heart attack or experiencing chest pain during the first month after they were discharged from the hospital. They were only half as likely as those with the least Mediterranean eating habits to have another heart-related event within a year, and nearly 40% less likely to experience repeat heart problems within two years.
Total fat and the type of fat consumed have a much greater impact on blood cholesterol and subsequent heart disease risk than dietary cholesterol. Mainly, feel confident that the heart-healthy properties of a low-fat, omega-3 rich food like fish will outweigh the negative impact of its cholesterol content. As with the healthiest vegetable oils and butter substitutes, the fat in fish is liquid at room temperature. Monounsaturated and polyunsaturated fish oils appear to not raise LDL cholesterol; some studies suggest these and all such unsaturated fats help lower LDL cholesterol.
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