chapter_5_Lipids_outline

What are lipids?

Category of compounds containing carbon, hydrogen and oxygen that are hydrophobic (insoluble in water).

What are the functions of fat in the body?

Major energy storage, shock absorbers, insulator (controlling body temperature), cell membranes, transport of proteins in blood.

What are the four main types of lipids?

Fatty acids, triglycerides, phospholipids, sterols.

What is a triglyceride composed of?

1 glycerol and 3 fatty acids.

What are fatty acids?

Chains of carbon and hydrogen atoms with an acid group (COOH) at one end.

What differentiates saturated fatty acids from unsaturated ones?

Saturated fatty acids have no double bonds between carbon atoms, while unsaturated fatty acids contain one or more double bonds.

How do lipids enter and exit a fat cell?

Lipids enter from the blood and exit to the blood through the cell membrane.

What are phospholipids used for in the body?

They act as emulsifiers to keep oils and water mixed together, and form cell membranes.

What is cholesterol's role in the body?

Cholesterol plays an important role in cell membrane structure and is a precursor for vital compounds like vitamin D and sex hormones.

What are lipoproteins?

Lipoproteins are compounds that transport lipids in the blood.

What is the function of chylomicrons?

Chylomicrons transport fat and cholesterol from a meal via the lymphatic system to cells.

What is atherosclerosis?

The narrowing of arteries due to the buildup of lipid-rich plaques.

What are the characteristics of metabolic syndrome?

Excess abdominal body fat, high triglycerides, low HDL, elevated blood pressure, and elevated fasting blood glucose.

What dietary sources contain omega-3 fatty acids?

Fish, walnuts, flaxseeds, and certain vegetable oils.

What should the percentage of calories from fat be in a healthy diet?

20-35% of total calories.

What should the intake of saturated fat/trans fat be limited to?

Less than 10% of total calories.

How is fat stored in the body?

Excess calories are stored as triglycerides in adipocytes (fat cells).

What is the primary source of saturated fats?

Animal products such as fatty meats, whole milk, butter, and lard.

What is the recommended fish intake for health?

Eat fish 2-3 times per week.

What happens to LDL not taken up by cells?

They degrade over time and may release cholesterol that adheres to blood vessel walls.

How does bile aid in fat digestion?

Bile emulsifies fat, making it easier for digestive enzymes to break it down.

What are trans fats and their health implications?

Trans fats are created during hydrogenation and can increase risk of heart disease.

What factors can help improve blood lipid levels?

Decrease LDL levels and increase HDL levels.

What does the consumption of essential fatty acids help produce?

Molecules like alpha-linolenic acid and arachidonic acid.

What are healthier sources of fats in the diet?

Vegetable oils, nuts, seeds, and lean meats.

What environmental contaminant is a concern with fish consumption?

Mercury, which is harmful especially to the nervous systems of unborn children.

What is the role of high-density lipoproteins (HDL)?

HDLs pick up cholesterol from cells and return it to the liver, helping to remove it from the bloodstream.

What percentage of the world's adults are estimated to have metabolic syndrome?

Approximately ¼ of adults.

What health problem is characterized by the narrowing of arteries?

Atherosclerosis.

What should individuals do to manage cardiovascular disease risk?

Eat a diet rich in plant foods, limit saturated/trans fats, and maintain physical activity.