Good fats include monounsaturated and polyunsaturated fats. Bad ones include industrial-made trans fats. Saturated fats fall somewhere in the middle. All fats have a similar chemical structure: a chain of carbon atoms bonded to hydrogen atoms. What makes one fat different from another is the length and shape of the carbon chain and the number of hydrogen atoms connected to the carbon atoms.
Seemingly slight differences in structure translate into crucial differences in form and function. The worst type of dietary fat is the kind known as trans fat. It is a byproduct of a process called hydrogenation that is used to turn healthy oils into solids and to prevent them from becoming rancid. Trans fats have no known health benefits and that there is no safe level of consumption. Therefore, they have been officially banned in the United States.
Early in the 20 th century, trans fats were found mainly in solid margarines and vegetable shortening. As food makers learned new ways to use partially hydrogenated vegetable oils, they began appearing in everything from commercial cookies and pastries to fast-food French fries. Trans fats are now banned in the U.
Eating foods rich in trans fats increases the amount of harmful LDL cholesterol in the bloodstream and reduces the amount of beneficial HDL cholesterol. Trans fats create inflammation, which is linked to heart disease, stroke, diabetes, and other chronic conditions. They contribute to insulin resistance, which increases the risk of developing type 2 diabetes.
Saturated fats are common in the American diet. They are solid at room temperature — think cooled bacon grease, but what is saturated fat? Common sources of saturated fat include red meat, whole milk and other whole-milk dairy foods, cheese, coconut oil , and many commercially prepared baked goods and other foods.
The word "saturated" here refers to the number of hydrogen atoms surrounding each carbon atom. The chain of carbon atoms holds as many hydrogen atoms as possible — it's saturated with hydrogens. Is saturated fat bad for you? A diet rich in saturated fats can drive up total cholesterol, and tip the balance toward more harmful LDL cholesterol, which prompts blockages to form in arteries in the heart and elsewhere in the body.
A handful of recent reports have muddied the link between saturated fat and heart disease. One meta-analysis of 21 studies said that there was not enough evidence to conclude that saturated fat increases the risk of heart disease, but that replacing saturated fat with polyunsaturated fat may indeed reduce risk of heart disease. Two other major studies narrowed the prescription slightly, concluding that replacing saturated fat with polyunsaturated fats like vegetable oils or high-fiber carbohydrates is the best bet for reducing the risk of heart disease, but replacing saturated fat with highly processed carbohydrates could do the opposite.
Good fats come mainly from vegetables, nuts, seeds, and fish. They differ from saturated fats by having fewer hydrogen atoms bonded to their carbon chains. Healthy fats are liquid at room temperature, not solid. There are two broad categories of beneficial fats: monounsaturated and polyunsaturated fats. Monounsaturated fats. When you dip your bread in olive oil at an Italian restaurant, you're getting mostly monounsaturated fat.
Monounsaturated fats have a single carbon-to-carbon double bond. The result is that it has two fewer hydrogen atoms than a saturated fat and a bend at the double bond. This structure keeps monounsaturated fats liquid at room temperature. BMJ, Manson, and W. Willett, Types of dietary fat and risk of coronary heart disease: a critical review. J Am Coll Nutr, The contents of this website are for educational purposes and are not intended to offer personal medical advice.
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Top of the page. Topic Overview Fats are nutrients that give you energy. Saturated fat Saturated fat is solid at room temperature, which is why it is also known as "solid fat. Trans fat This is a fat that has been changed by a process called hydrogenation. Unsaturated fat Unsaturated fat is liquid at room temperature. Monounsaturated fat: This fat is in avocado, nuts, and vegetable oils, such as canola, olive, and peanut oils.
Eating foods that are high in monounsaturated fats may help lower your "bad" LDL cholesterol. Monounsaturated fats may also keep "good" HDL cholesterol levels high. But eating more unsaturated fat without cutting back on saturated fat may not lower your cholesterol. Polyunsaturated fat: This type of fat is mainly in vegetable oils such as safflower, sunflower, sesame, soybean, and corn oils. Polyunsaturated fat is also the main fat found in seafood. Eating polyunsaturated fat in place of saturated fat may lower LDL cholesterol.
The two types of polyunsaturated fats are omega-3 and omega-6 fatty acids. Omega-3 fatty acids are found in foods from plants like soybean oil, canola oil, walnuts, and flaxseed. Omega-6 fatty acids are found mostly in liquid vegetable oils like soybean oil, corn oil, and safflower oil. Total fat Total fat includes saturated, polyunsaturated, monounsaturated, and trans fat. Health Tools Health Tools help you make wise health decisions or take action to improve your health.
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