Nutrition Science Chapter 5 Quiz

Lipids and Their Classification

• Lipids include substances such as sterols, triglycerides, and phospholipids.
• The most common lipids in food are triglycerides, which the body stores as fat.
• A triglyceride consists of three fatty acids and one glycerol molecule.

Characteristics of Triglycerides

• Triglycerides can be categorized based on the shape, length, and saturation of their fatty acids.
• Fatty acids can vary in chain length and saturation, affecting their properties and behavior in the body.

Types of Fatty Acids

• Monounsaturated fatty acids, such as those with a 10-carbon chain and one double bond, have beneficial health effects.
• Saturated long-chain fatty acids contain no double bonds and are typically solid at room temperature.

Sources of Fatty Acids

• Foods rich in saturated fatty acids include butter, while corn oil is a prime source of polyunsaturated fatty acids.
• Essential fatty acids include linoleic and alpha-linolenic acid, which play significant roles in heart health.

Trans Fatty Acids

• Trans fatty acids form through hydrogenation, a process that adds hydrogen to unsaturated fatty acids.
• Diets high in trans fatty acids are linked to increased blood cholesterol levels.
• Ingredients like hydrogenated vegetable oil indicate the presence of trans fatty acids in food products.

Role of Essential Fatty Acids

• Essential fatty acids are critical precursors for producing eicosanoids, which are important biological compounds that regulate various body functions.
• Alpha-linolenic acid is particularly noted for its heart-protective properties.

Phospholipids

• Phospholipids are not essential nutrients since the body can manufacture them.
• Lecithins, a type of phospholipid, act as emulsifiers in food, helping to blend ingredients that typically don't mix well.