Introduction
Abnormal lipids have long been known to increase the chance of developing coronary artery disease, which can potentially result in a heart attack. At first, increased cholesterol levels were thought to constitute a risk, but today, even atypical components, as seen in dyslipidemia, are classified as risk factors. Fat metabolism is an intricate process. Excess fat and lipid levels can precipitate various diseases, affecting the cardiovascular system.
What Are Lipids?
Found in the bloodstream and throughout the body, lipids are molecules that play important roles in living organisms. Although they primarily act as energy reservoirs, they also play essential roles in protection, insulation, and lubrication for all the cells of the body. They are fatty, oily, and waxy and are primarily composed of carbon, oxygen, and hydrogen molecules.
What Are the Different Types of Lipids?
There are three basic groups of lipids, namely:
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Phospholipids: They contribute to two percent of dietary lipids. For the body’s cells to function efficiently and have a protective barrier or outer membrane, it is crucial to consume phospholipids.
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Sterols: They are the lesser-known type of lipids but are essential as they are required for the synthesis of vitamin D, bile salts, and sex hormones. Cholesterol is a classic example of sterols.
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Triglycerides: Also known as triacylglycerols, they make up at least 95 percent of the lipids in the diet and are usually found in processed food, fried food, vegetable oils, milk, butter, cheese, and some meats. They are also found in corn, avocados, and nuts.
What Are the Various Function of Lipids in the Body?
Lipids are associated with the following primary biological functions of the body -
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Energy Storage Reservoir: The energy provided by the diet is stored in the adipose tissues of the body (otherwise known as fat cells). When the body is deficient in energy, for example, when an individual is fasting, these fat cells provide energy to the body to meet the requirements.
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Regulate Body Temperature: The lipids present in the body often act as the body’s temperature regulators. People having less fat percentage tend to feel cold and experience fatigue. Additionally, fatty acid deficiency also leads to pressure sores.
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Regulate and Signal Hormone Production: Lipids are required for the production of several hormones, for example, female hormones. Omega-3 fatty acids play a crucial role in regulating cholesterol levels and blood clotting factors.
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Insulates and Protects the Body From Extreme Temperatures: Fatty tissue insulates the body from extreme temperatures and maintains the internal body temperature.
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Aid Digestion: Lipids help in the digestion of fat-soluble nutrients (vitamins A, D, E, and K) and also increase their bioavailability for the body’s efficient utilization.
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Help Functional Processes of the Body: Lipids also help in several functional processes, such as memory storage, nerve impulse transmission, and formation of tissues. They also participate in the formation of membranes of the nerve cells and help improve brain activity and its functions.
What Is Cholesterol?
Cholesterol is the most common form of sterols. Produced by the liver, it is essential for the normal functioning of the body. A few functions of cholesterol are as follows:
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Synthesize various hormones, such as sex hormones, and glucocorticoids.
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Produce bile (a digestive fluid made and released by the liver). It helps in the breakdown of complex lipids and fats into simpler derivatives.
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Synthesize vitamin D, a fat-soluble vitamin that plays a crucial role in regulating phosphorus and calcium in the body.
What Are Lipoproteins?
They are a type of protein on which cholesterol molecules adhere and travel through the bloodstream. Lipoproteins are of three types:
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LDL or Low-Density Lipoprotein - Otherwise known as bad cholesterol.
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VLDL or Very Low-Density Lipoprotein - They are also known as bad cholesterol.
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HDL or High-Density Lipoprotein - Otherwise known as good cholesterol.
LDL and VLDL travel through the bloodstream, delivering to the cells that need them. An increase in their levels precipitates fatty deposition and accumulation in the walls of blood vessels. These deposits hamper normal blood flow, making LDL and VLDL a type of bad cholesterol. An increase in their levels can make people susceptible to heart disease. In contrast, HDL molecules absorb the excess or unwanted cholesterol present in the body and route it to the liver. On reaching the liver, numerous processes are initiated that flush the excess cholesterol from the body. Hence, HDL is termed good cholesterol as it reduces cardiovascular disease risk.
What Are the Normal Ranges of LDL and HDL for an Individual?
The normal ranges of HDL and LDL can vary from one individual to another. However, the optimal ranges of LDL for an adult are as follows:
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Optimal Range - Less than 100 mg/dL (milligrams per decilitre).
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Near-optimal Range - 100-129 mg/dL (for patients with prior history of heart disease).
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Borderline High - 130-159 mg/dL.
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High - 160-189 mg/dL.
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Extremely High - 190 mg/dL and above.
The adult ranges for HDL start with 40 mg/dL. A high level of HDL indicates good protection against cardiovascular diseases.
What Happens When the Blood Lipids Are Elevated?
When the levels of blood lipids increase, they precipitate a medical condition commonly known as dyslipidemia or hyperlipidemia. Such an abnormal increase in lipid levels can lead to various diseases and put the organs at risk. Hyperlipidemia is a common condition and can affect people of all ages. Hyperlipidemia is also the primary cause of cardiovascular disease. It makes people susceptible to atherosclerosis, a condition characterized by the accumulation of fats in the blood vessels that carry oxygen-rich blood. This, in turn, makes the blood vessels stiff, impairing their elasticity and also decreasing their cross-sectional lumen, both of which impede efficient blood flow.
What Are the Risk Factors for Hyperlipidemia?
The following factors make a person susceptible to hyperlipidemia:
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Tobacco abuse.
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Excessive stress.
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Diminished or absent physical activity and exercise.
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Obesity.
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Unhealthy diet, especially involving excessive amounts of processed foods.
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Alcohol abuse.
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Increased blood sugar levels.
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Underactive thyroid.
What Are the Symptoms Associated With Hyperlipidemia?
Increased cholesterol, as such, does not have any associated symptoms. Symptoms are only elicited when other organ systems have been affected by hyperlipidemia and fail to function properly. Following are cardiovascular symptoms elicited by a hyperlipidemic patient:
- Chest pain.
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Shortness of breath.
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Jaw pain.
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Chest pain radiating to the back, shoulders, and arms.
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Chest tightness.
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Increased blood pressure.
What Are the Consequences of Hyperlipidemia?
The presence of excess or unwanted fat leads to the exertion of the heart and its associated structures, increasing the risk of cardiovascular diseases. Fats and lipids accumulate within the blood vessels, blocking them. This blockage impedes heart function as it limits blood and oxygen supply. If not managed appropriately, hyperlipidemia can lead to the following conditions:
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Stroke.
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Coronary heart disease.
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Peripheral artery disease.
What Measures Can People Take To Manage Their Lipid Levels?
People can take the following measures to keep themselves healthy and free of cardiovascular diseases:
1. Blood Tests - A lipid screening, also known as a lipid profile and lipid panel, allows people to track the lipid content in the blood.
2. Dietary Modifications - Consuming a healthy diet, having good amounts of fruits and vegetables, and healthy fats can help people prevent hyperlipidemia. Minimal consumption of processed food, trans fats, and alcohol can help effectively manage lipid levels.
3. Lifestyle Modifications - It is important to be physically active to effectively manage lipid levels. People should aim to devote at least 30 minutes a day to activities like walking, running, cycling, swimming, weight lifting, resistance training, or any outdoor sport. Mediation and yoga can also be incorporated to help deal with stress.
4. Medications - Doctors may prescribe certain medications to hyperlipidemic patients, such as:
- Statins: Such as Atorvastatin or Lovastatin.
- Cholesterol Absorption Inhibitors: For example, Ezetimibe.
- Bile Acid Sequestrants: Such as Cholestyramine and Colestipol.
Conclusion
Lipids are fatty molecules found in the blood and throughout the body. They play crucial roles and aid in the normal functioning of the body and various organ systems. An abnormal increase in lipid levels commonly referred to as hyperlipidemia and dyslipidemia, exerts an excess load on the cardiovascular system. The heart tends to work harder to distribute blood, nutrients, and oxygen. Several measures can be taken to ensure a balance in the levels of lipids and prevent cardiovascular diseases. A combination of a healthy diet, routine check-ups, exercise, de-stressing activities, and medication (for patients wherein the other methods fail to provide results) can help improve the levels of good cholesterol and decrease the levels of bad cholesterol, thereby aiding heart health.
