Dietary fats are nutrients that help your body store energy, build cell membranes, absorb certain vitamins, and make hormones. Not all fats affect the body in the same way, so the type of fat matters as much as the amount. Healthy unsaturated fats are found in foods such as nuts, seeds, avocados, olive oil, and many fish.
Trans fats and too much saturated fat can raise the risk of heart and blood vessel problems over time.
Key Facts
- Unsaturated fats are usually liquid at room temperature and are common in olive oil, canola oil, nuts, seeds, avocado, and fish.
- Saturated fats are usually solid at room temperature and are found in butter, cheese, fatty meats, coconut oil, and palm oil.
- Trans fats can raise LDL cholesterol and lower HDL cholesterol, which makes them especially harmful for heart health.
- Energy from fat = 9 Calories per gram, while carbohydrates and proteins each provide about 4 Calories per gram.
- Total fat Calories = grams of fat x 9.
- A healthy pattern replaces trans fats and excess saturated fats with unsaturated fats rather than adding extra fat on top of the usual diet.
Vocabulary
- Unsaturated fat
- A type of fat with one or more carbon carbon double bonds that is often liquid at room temperature and can support heart health when used in place of less healthy fats.
- Saturated fat
- A type of fat with no carbon carbon double bonds that is often solid at room temperature and should be limited when eaten in excess.
- Trans fat
- A type of unsaturated fat with a trans chemical shape that is often made during partial hydrogenation and is linked to worse cholesterol levels.
- LDL cholesterol
- A blood particle often called bad cholesterol because high levels can contribute to plaque buildup in arteries.
- HDL cholesterol
- A blood particle often called good cholesterol because it helps carry cholesterol away from arteries.
Common Mistakes to Avoid
- Calling all fats unhealthy is wrong because the body needs fat for energy storage, cell membranes, brain function, and vitamin absorption.
- Choosing low fat foods without checking added sugar is a mistake because some low fat products replace fat with sugar or refined starches.
- Thinking saturated fat and trans fat are the same is wrong because trans fat has a different chemical shape and is more strongly linked to unhealthy cholesterol changes.
- Adding healthy oils without replacing less healthy fats is a mistake because total Calories can still become too high even when the fat source is healthier.
Practice Questions
- 1 A snack has 12 grams of fat. How many Calories from fat does it contain?
- 2 A salad dressing has 8 grams of unsaturated fat and 2 grams of saturated fat per serving. What percent of its fat grams are unsaturated?
- 3 A student says, 'Avocado and fried dough both contain fat, so they affect the body the same way.' Explain why this statement is inaccurate using the difference between fat types and food choices.