Vegetable oils contain unsaturated fats.
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Eating a healthy diet requires making sure that you take in the proper amount and proportions of carbohydrates, proteins and fats. Just as there are carbohydrates that are good for you and types that are bad, so it is with fats. There are three basic kinds of fats. Unsaturated fats, which offer the most benefits per calorie, saturated fats which can be problematic in large quantities and trans fats, which should be avoided due to their ill effects on your body. Understanding the different types of fats can help you make healthier food choices.
How Your Body Breaks Down Fats
Fats take longer to break down in the body and must undergo a slightly more complicated process than simpler foods such as sugars. Fats go from your stomach to your small intestine, and once there are bathed in bile from your gallbladder. The bile emulsifies the fats, just like when you add vinegar to olive oil.
During this process, the chemical chains holding the two components of the fats together are broken. The two parts, fatty acids and glycerol, are absorbed by your intestines and sent to your liver.
Once the fatty acids and glycerol reach your liver, they are either broken down for use as energy, or stored in your body to help protect your organs, to aid in the digestion of fat-soluble vitamins, or to be used for energy later.
Understanding Unsaturated Fats
Unsaturated fats come mostly from fish, nuts, olives and seeds. They tend to stay liquid at room temperature because they have a lower melting point than saturated fats.
This is the healthiest type of fat. Unsaturated fats offer essential fatty acids which help lower the levels of low-density lipoproteins, or LDLs, which is unhealthy cholesterol. They also help raise the level of high-density lipoproteins, or HDLs, which help keep your bloodstream free of unhealthy fats.
Unsaturated fats also have high levels of vitamin E, which is a powerful antioxidant. Vitamin E helps scrub free radicals out of your bloodstream. Free radicals are like rust on your cells, and they contribute to the development of certain cancers and cause the more visible signs of aging.
Simple Facts About Saturated Fats
Saturated fats come mostly, but not only, from animal sources such as beef, pork, chicken and cheeses. They are not broken down quickly by your body and can linger in your bloodstream, clogging your arteries and putting you at risk for heart attack, stroke and certain kinds of cancer.
Choose the leanest types of meat, such as chicken, drink low-fat milk and consider substituting nonfat plain yogurt for sour cream whenever possible to keep your intake of saturated fats at a healthy level.
The Trouble With Trans Fats
Trans fats are not often found in the natural world. They were discovered when scientists bonded oils with hydrogen to create margarine and other partially hydrogenated oils. This was a huge discovery in the world of commercial baking, because it vastly prolonged the shelf life of unrefrigerated breads, cakes, pastries and cookies.
Because trans fats do not occur naturally in foods, your body is not equipped to process them efficiently. The saturated fats in trans fats are even more stubborn about remaining in your bloodstream than natural saturated fats, clogging your arteries and elevating your risk of developing heart disease, suffering a stroke or developing cancer. It's best to avoid margarine and any mass-produced baked goods that do not have to be refrigerated.