Essential fatty acids are the ones which you need to get from the diet because your body cannot synthesize them, and the only essential fatty acids are linoleic acid and alpha-linolenic acid. The other fatty acids are not essential, because you can survive without getting them from your diet, and some are healthier than others. Choose the healthiest kinds, and eat fats only in moderation to prevent unwanted weight gain, since they are high in calories. A nutritionist can help you choose the best sources of fatty acids and plan appropriate amounts to include in your diet.
Monounsaturated Fatty Acids
Your body can make mononunsaturated fatty acids, but health benefits of getting higher amounts from your diet may include lower levels of low-density lipoproteins, or LDL, cholesterol in your blood and lower blood pressure, according to MayoClinic.com. Good sources include avocados, olive oil, canola oil and peanut oil. Although there is no daily value for them, aim to get 10 to 25 percent of your total calories from monounsaturated fatty acids, according to the Harvard School of Public Health. This means about 22 g to 55 g per day for a 2,000-calorie diet.
Non-Essential Polyunsaturated Fatty Acids
The only essential polyunsaturated fatty acids are linoleic acid, an omega-6 fat, and alpha-linolenic acid, an omega-3 fat, and the rest are non-essential, according to the Linus Pauling Institute Micronutrient Information Center. Most Americans get plenty of non-essential polyunsaturated fatty acids, and good sources include nuts, vegetable oils, seeds and peanuts. Fatty fish and shellfish supply long-chain omega-3 polyunsaturated fatty acids, which may lower your risk for heart disease. The Harvard School of Public Health recommends getting about 10 percent of your calories from polyunsaturated fats, or about 22 g per day on a 2,000-calorie diet.
Saturated Fatty Acids
Saturated fatty acids are not essential in your diet, and they are unhealthy because they raise your cholesterol levels. Some of the top sources of solid fats in the typical American diet are full-fat cheeses, fatty meats, such as ribs, bacon and sausages, baked desserts, pizza and ice cream, according to the 2010 Dietary Guidelines from the USDA Department of Health and Human Services. Limit your intake to no more than 7 to 10 percent of your total calories, or 15.5 to 22 g per day on a 2,000-calorie diet, according to MayoClinic.com.
Trans Fatty Acids
Trans fatty acids may be the worst kind of fat because they raise your bad LDL cholesterol and lower your good high-density lipoprotein, or HDL, cholesterol levels, according to the Harvard School of Public Health. Trans fatty acids result from the process of making fats more solid by adding hydrogen atoms to unsaturated oils. This is useful in the food industry because hydrogenated fatty acids are more solid, a desirable texture in food products such as snack cakes or crackers. Even increasing your daily intake of trans fatty acids by a small amount raises your risk for heart disease, so aim for no more than 2 g per day.
- MayoClinic.com: Dietary Fats: Know Which Types to Choose
- MayoClinic.com; MUFAs: Why Should My Diet Include These Fats?; Katherine Zeratsky; November 2010
- Harvard School of Public Health: Fats and Cholesterol: out with the Bad, in with the Good
- U.S. Department of Health and Human Services; Dietary Guidelines for Americans, 2010; January 2010