Fats and Cholesterol Flashcards
Changing Views of Fats and Cholesterol
-American adults are being urged to select food sources of healthy fats while keeping fat intake with in range of 20-35% of total caloric intake
(Average USA fat consumption 33%)
-Diets providing as low as 20% of calories from fat and those providing 30%-35% of calories from fat can be healthy
Function of Dietary Fat
- Concentrated source of energy
- Body’s energy reserves (fat stores)
- Carries the essential fatty acids the fat soluble vitamin and certain phytochemicals
- Increase the flavor and palatability of food
- Provides sustained relief from hunger
- Serves as component of cell membrane, vitamin D, sex hormones
Types of Fat
- Saturated Fat
- Unsaturated Fat (Monounsaturated /Polyunsaturated)
- Trans Fat
Saturated Fat
- Stays solid at room temperature
- Can raise cholesterol
- Have chemical makeup in which the carbon atoms are attached to as many hydrogen atoms as possible (saturated with hydrogen)
- Majority come from animal sources (Fatty beef, cream, butter, cheese also fried food, coconut oil, palm oil)
- The AHA recommends limiting saturated fats to less than 7% of calories (140 calories of 2,000 diet =16grams)
Monounsaturated Fat
- Liquid at room temperature but solidify somewhat refrigerated usually found in plant source
- Container fewer hydrogen than the maximum
- Ex: olive oil, peanut butter, sesame oil, avocados
- Have one double bonded carbon in the molecule
- Can have benefits if used in moderation
Polyunsaturated Fat
- Liquid at room temperature
- Simple fats that have more than one double bonded carbon in the molecule
- Can have beneficial effects when used in moderation and used to replace saturated fats
- Also include essential fats that the body needs but can not produce (Omega-6 & Omega-3)
- Examples: corn oil, fatty fish (salmon, trout), walnuts, sunflower seeds, flaxseed
Essential Fatty Acids
- Linoleic Acid (omega 6)
- Alpha Linoleic Acid (omega 3)
Linoleic Acid / Omega 6 (Essential Fatty Acids)
Required for growth, maintenance of healthy skin, normal function of the reproductive system
- Found in high amounts in nerves and the brain
- Helps participate in regulation of blood pressure and blood clotting
- Major sources: sunflower, corn, safflower, soybean oil
Alpha Linoleic Acid / Omega 3 (Essential Fatty Acids)
Found in high amounts in the brain and other nervous systems tissue
- Forms biologically active compounds used in the regulation of blood pressure and blood clotting
- Found in walnuts, dark leafy green vegetables, flaxseed, canola and soybean oil
- Other biological important omega 3 fatty acids exist and the two primary ones are EPA and DHA
EPA and DHA
Primarily ingredients of fish oils and perform a number of important functions in the body
-On average adults in the US & Canada consume 100 mg of EPA plus DHA daily short of the recommended intake of 500 mg
DHA
Structural component of the brain and is found in high amounts in the retina of the eye; also important during the last three months of pregnancy and during infancy DHA accumulates in these tissues and promotes optimal intellectual and visual development
EPA
Serves as a precursor of a number of biologically active compounds involved in blood pressure regulation, blood clotting, and anti-inflammatory reactions
Hydrogenated Fat/Trans Fat
- Created by adding hydrogen to liquid vegetable oils to make them more solid - shelf life, cooking properties, and taste are improved in the process
- Hydrogenated vegetables oils contain more saturated fat than the original oil (corn oil – 6% saturated fat corn oil margarine – 17% saturated fat)
- Hydrogenation causes a change in the structure of the unsaturated fatty acid
- EX: margarine, shortening, baked goods, pastries companies are decreasing or eliminating use
Effects of Hydrogenated Fat/Trans Fat
Adverse affect on blood lipids and increase risk of heart disease, stroke, death from heart disease, type 2 diabetes, Raise LDL cholesterol and lower HDL cholesterol
(Before 1990 very little was known about the adverse health effects)
Cholesterol
- Lipid found primarily in animal products
- About 75% of cholesterol in the body is produced by the liver and the brain (makes it own supply)
