Unit 5 – Lipids: Fats, Oils, and Cholesterol
Because heart disease, cancer, and stroke are the three leading causes of death in the United States, it is critical to address dietary and lifestyle choices that will ultimately decrease risk factors for these diseases. According to the US Department of Health and Human Services (HHS), the following risk factors are controllable: high blood pressure, high cholesterol, cigarette smoking, diabetes, poor diet, physical inactivity, being , and
In light of that, we present the following informational tips to help you define, evaluate, and implement healthy dietary choices to last a lifetime. The amount and the type of fat that composes a person’s dietary profile will have a profound effect upon the way fat and cholesterol is metabolized in the body.
Watch Out for Saturated Fat and Cholesterol
In proper amounts, is a compound used by the body to sustain many important body functions. In excess, cholesterol is harmful if it accumulates in the structures of the body’s vast network of blood vessels. High blood and low blood are major indicators of blood cholesterol risk. The largest influence on blood cholesterol levels rests in the mix of saturated fat and trans fat in the diet.
According to the Harvard School of Public Health, for every extra 2 percent of calories from trans fat consumed per day—about the amount found in a midsize order of French fries at a fast-food establishment—the risk of coronary heart disease increases by 23 percent. A buildup of cholesterol in the blood can lead to brittle blood vessels and a blockage of blood flow to the affected area.
How saturated is the fat in your diet? Is it really necessary to eat when the body makes all the saturated fat that it needs? Saturated fats should fall into the “bad” category—the body does not demand this kind of fat and it is proven to be a forerunner of cardiovascular disease. In the United States and other developed countries, populations acquire their saturated fat content mostly from meat, seafood, poultry (with skin consumed), and whole-milk dairy products (cheese, milk, and ice cream). Some plant foods are also high in saturated fats, including coconut oil, palm oil, and palm kernel oil.
Effect Dietary Cholesterol on Blood Cholesterol
Dietary cholesterol does have a small impact on overall blood cholesterol levels, but not as much as some people may think. The average American female consumes 237 milligrams of dietary cholesterol per day and for males the figure is slightly higher—about 358 milligrams. Most people display little response to normal dietary cholesterol intake as the body responds by halting its own synthesis of the substance in favor of using the cholesterol obtained through food. Genetic factors may also influence the way a person’s body modifies cholesterol. The 2015-2020 and 2020-2025 US Dietary Guidelines suggest limiting saturated fats, thereby indirectly limiting dietary cholesterol since foods that are high in cholesterol tend to be high in saturated fats
A Prelude to Disease
If left unchecked, improper dietary fat consumption can lead down a path to severe health problems. An increased level of lipids, triglycerides, and cholesterol in the blood is called hyperlipidemia. Hyperlipidemia is inclusive of several conditions but more commonly refers to high cholesterol and triglyceride levels. When blood lipid levels are high, any number of adverse health problems may ensue. Consider the following:
- Cardiovascular disease. According to the AHA, cardiovascular disease encompasses a variety of problems, many of which are related to the process of atherosclerosis. Over time the arteries thicken and harden with plaque buildup, causing restricted or at times low or no blood flow to selected areas of the body.
- Heart attack. A heart attack happens when blood flow to a section of the heart is cut off due to a blood clot. Many have survived heart attacks and go on to return to their lives and enjoy many more years of life on this earth. However, dietary and lifestyle changes must be implemented to prevent further attacks.
- Ischemic stroke. The most common type of stroke in the United States, ischemic stroke, occurs when a blood vessel in the brain or leading to the brain becomes blocked, again usually from a blood clot. If part of the brain suffers lack of blood flow and/or oxygen for three minutes or longer, brain cells will start to die.
- Arrhythmia. This is an abnormal rhythm of the heart. The heart may beat above one hundred beats per minute (known as tachycardia) or below sixty beats per minute (known as bradycardia), or the beats are not regular. The heart may not be able to pump enough volume of blood to meet the body’s needs.
- Obesity. Obesity is defined as the excessive accumulation of body fat. According to US Surgeon General Richard Carmona, obesity is the fastest growing cause of death in America. The HHS reports that the number of adolescents who are overweight has tripled since 1980 and the prevalence of the disease among younger children has doubled. Obesity has been linked to increased risks of developing diabetes and heart disease. To help combat this problem important dietary changes are necessary. Reducing the type and amount of carbohydrates and sugar consumed daily is critical. Limiting the intake of saturated fats and trans fats, increasing physical activity, and eating fewer calories are all equally important in this fight against obesity.
What You Can Do
Remember to eat less saturated fats that are found in large amounts in foods of animal origin. Polyunsaturated fats are generally obtained from non-animal sources. While they are beneficial for lowering bad cholesterol they also lower good cholesterol. They are better for you than saturated fats but are not to be consumed in excess. Monounsaturated fats are of plant origin and are found in most nuts, seeds, seed oils, olive oil, canola oil, and legumes. Monounsaturated fats are excellent because they not only lower bad cholesterol, but also they elevate the good cholesterol. Replace current dietary fats with an increased intake of monounsaturated fats.
The acceptable macronutrient distribution range (AMDR) from the Dietary Reference Intake Committee and recommendations for adult fat consumption from the Dietary Guidelines for Americans are as follows:
- Fat calories should be limited to 20-35 percent of total calories, with most fats coming from polyunsaturated and monounsaturated fats, such as those found in fish, nuts, and vegetable oils.
- Consume fewer than 10 percent of calories from saturated fats. The Percent Daily Value is based on 2,000 calories a day, so more than 200 calories should come from saturated fat. Recall that there are 9 calories in a gram of fat, so 200 divided by 9 is 22.2, or about 22 grams. (The American Heart Association recommends limiting saturated fat to 5 to 6 percent of calories, which is 11 to 13 grams per day.)
- Keep the consumption of trans as low as possible. As manufactured trans fats have been phased out of the U.S. food supply, Americans don’t have to worry as much about identifying and avoiding trans fats. However, they’re still used in other parts of the world. Beef is the main source of natural trans fat in the US food supply.
- Choose more lean and low-fat products when selecting meat, poultry, milk, and dairy products.
Choose whole-grain and high-fiber foods. Reduced risk for cardiovascular disease has been associated with diets that are high in whole grains and fiber. Fiber also slows down cholesterol absorption. At least half of daily grain intake should originate from whole grains. The Adequate Intake value for fiber is 14 grams per 1,000 kilocalories. These amounts are based upon the amount of fiber that has been shown to reduce cardiovascular risk.
Do not be sedentary. Get more exercise on a regular basis. Increasing your energy expenditure by just 20 minutes of physical activity at least three times per week will improve your overall health. Physical exercise can help you manage or prevent high blood pressure and blood cholesterol levels. Regular activity raises HDL while at the same time decreases triglycerides and plaque buildup in the arteries. Calories are burned consistently, making it easier to lose and manage weight. Circulation will improve, the body will be better oxygenated, and the heart and blood vessels will function more efficiently.
In addition to dietary changes, don’t forget the value of physical activity. Physical inactivity increases the risk of heart disease. Physical exercise can help manage or prevent high blood pressure and high blood cholesterol. Regular activity raises HDL while also decreasing triglycerides and plaque buildup in the arteries. And activity consistently burns calories, which can help with weight loss or maintaining a healthy weight
- Lane Community College’s Nutrition: Science and Everyday Application “Classification of Nutrients ” CC BY-NC 4.0
- 1) Fats and Cholesterol: Out with the Bad, In with the Good. Harvard School of Public Health. http://www.hsph.harvard.edu/nutritionsource/what-should-you -eat/fats-full-story/. Updated 2017. Accessed September 28, 2017. ↵
- 2) Dietary Guidelines for Americans 2015–2020 8th Edition. (n.d.). Retrieved from https://health.gov/dietaryguidelines/2015/guidelines/ ↵
- 3) Dietary Guideilns for Americans 2020-2025 9th Ediction (n.d.) Retrieved from https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf ↵
- 4) Childhood Obesity. US Department of Health and Human Services. http://aspe.hhs.gov/health/reports/child_obesity/. Published May 1, 2005. Accessed October 5, 2012 ↵
- 5) Forouhi, N. G., Krauss, R. M., Taubes, G., & Willett, W. (2018). Dietary fat and cardiometabolic health: evidence, controversies, and consensus for guidance. Bmj, 361, k2139.
- “Traditional stethoscope with a red heart” by Marco Verch is licensed under CC BY 2.0
- “Pile of Donuts” by Anna Sullivan is in the Public Domain, CC0
- Figure 5.29. “Healthy Meal” by Louis Hansel is in the Public Domain, CC0; Healthy Brunch Photo by “Healthy Brunch” by Jannis Brandt is in the Public Domain, CC0; “Concept Diet” by Marco Verch is licensed under CC BY 2.0.
- “Heart-Shaped Bowl” by Jamie Street is in the Public Domain, CC0
- Fats and Cholesterol: Out with the Bad, In with the Good. Harvard School of Public Health. http://www.hsph.harvard.edu/nutritionsource/what-should-you -eat/fats-full-story/. Updated 2017. Accessed September 28, 2017. ↵
- Dietary Guidelines for Americans 2015–2020 8th Edition. (n.d.). Retrieved from https://health.gov/dietaryguidelines/2015/guidelines/ ↵
- Dietary Guideilns for Americans 2020-2025 9th Ediction (n.d.) Retrieved from https://www.dietaryguidelines.gov/sites/default/files/2020-12/Dietary_Guidelines_for_Americans_2020-2025.pdf ↵
- Childhood Obesity. US Department of Health and Human Services. http://aspe.hhs.gov/health/reports/child_obesity/. Published May 1, 2005. Accessed October 5, 2012 ↵
Have a BMI between 25 up to 30, or weighing about 25 lbs more than is desirable.
WHO considers it as an "abnormal or excessive fat accumulation that may impair health." Having a BMI over 30. Most people weigh 50 pounds or more than is desirable.
A lipid in the sterol family found only in animal products.
Low desnsity lipoproteins. Transports cholesterol to various tissues in the body. High levels associated with increased risk of cardiovascular disease.
High density lipoproteins. Function in removing cholesterol from body tissued. High levels are associated with improved health outcomes.
Fats that are solid at room temeperature and have no double bonds.