Known as lipid, cholesterol is a fatty substance found naturally in the body. It is mainly made by the liver but it is also present in the food you eat. Your body needs cholesterol to function properly, as it is present in the membranes of every cell in the body, including the brain, muscles, nerves, liver, skin, heart, and intestines. Cholesterol is not water-soluble and cannot travel freely in your blood unless it pairs itself with proteins to form lipoprotein, which helps transport cholesterol through your bloodstream. Lipoproteins can be divided into two categories – one is low-density or LDL and the other one is high-density or HDL. Although both types of lipoproteins help transport cholesterol, they are not the same.

Main Difference Between HDL and LDL

It may seem that both HDL and LDL play the same role in the body, but that is not the case. In reality, they both have very different functions, structures, and effects on your health.

1.        Difference in Functions

Both types of lipoproteins transport cholesterol in the blood, but there is functional difference in how they deliver cholesterol to different parts of your body.

• LDL (Bad): LDLs are the primary carriers of cholesterol and take cholesterol to cells in your body. They can lead to plaque, so is considered bad for your health. Plaque is a thick, hard deposit that can cause blockage in arteries and lead to a condition called atherosclerosis. Sometimes, a clot forms in a narrowed artery and cuts blood flow, which results in a stroke or heart attack. Excessive plaque buildup in an artery supplying blood to the legs may contribute to the development of a condition called peripheral artery disease.
• HDL (Good): One major difference between HDL and LDL is that HDL has good effects on your body because it plays a big role in eliminating bad cholesterol from your arteries. It works as a scavenger and takes cholesterol away from your organs and heart. Then it delivers cholesterol back to your liver, where the cholesterol is broken down and eliminated from the body. It is important to have a healthy level of HDL cholesterol in your body to stave off cardiovascular disease, including heart attack and stroke.

2.        Difference in Structure

The structural difference between HDL and LDL is the composition of lipids and proteins.

• LDL: In terms of weight, 50% of LDL particle is cholesterol and 25% is protein. There is also a difference in the types of proteins present in HDL and LDL. Proteins called B-100 are present in low-density lipoproteins.
• HDL: In terms of weight, HDL particle consists of 50% protein and 20% cholesterol. Protein is denser as compared to fat, which is why HDL particles are denser as compared to LDL particles, which is why HDL particles are called "high density". HDL particles mainly consist of A-I and A-II proteins. The function of these particles changes due to a change in the types of proteins they contain.

How Much Cholesterol Is Too Much?

Doctors recommend that you should aim to keep your total cholesterol levels below 200 mg/dL. While less than 200 mg/dL is desirable, you are also safe between 200 and 239 mg/dL – although it makes you more susceptible to developing heart disease. Anything above 240 mg/dL is considered high.

You are at a serious risk for stroke, heart attack, and other problems if your LDL cholesterol levels are higher than 190 mg/dL. However, you need to aim for a higher level of HDL cholesterol because anything less than 40 mg/dL puts you at a greater risk for heart disease. Your doctor will consider your age, your medical history, and your blood pressure to determine the best lifestyle changes and medications to keep your cholesterol within the desirable range.

How to Lower Cholesterol Levels

Knowing the difference between HDL and LDL will always put you in a better position to understand how to maintain a balance between both types of lipoproteins. However, you can make some lifestyle changes to keep your cholesterol levels in check. For instance:

• Include food in your diet that contains less cholesterol, fat, and saturated fat.
• Avoid eating the skin and fat from poultry, meat, and fish.
• Avoid eating fried food and opt for baked, broiled, or poached food.
• Include lots of veggies and fruits in your diet.
• Eat whole wheat bread and rice or cereals made from whole grain.
• Consider losing weight if you are obese.
• Quit smoking.
• Stay active and do moderate exercise for about half an hour every day.
• Always take your cholesterol medications carefully, as per the instructions of your doctor.