We were urged to banish it from our diets whenever possible. We switched to low-fat foods. But the shift didn't make us healthier, probably because we cut back on healthy fats as well as harmful ones. You may wonder isn't fat bad for you, but your body needs some fat from food. It's a major source of energy. It helps you absorb some vitamins and minerals. Fat is needed to build cell membranes, the vital exterior of each cell, and the sheaths surrounding nerves.
It is essential for blood clotting, muscle movement, and inflammation. For long-term health, some fats are better than others. 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. You have successfully subscribed to our newsletter. Related Articles. How to Treat Reactive Hypoglycemia. Trending Topics. What Parents Need to Know. Share this article via email with one or more people using the form below. In addition, pure carbohydrate and protein have less than half the calories of pure fat, making them relatively weak sources of energy.
For these reasons, liver and muscle contain only a small fraction of the calories in fat tissue less than compared to about 3, per pound. In the absence of body fat, even a muscular man would waste away in days without eating, whereas all but the leanest adults have enough body fat to survive many weeks.
Fat tissue also responds to and emits a multitude of chemical signals and neural messages, helping fine-tune our metabolism and immune system. But when fat cells malfunction, big problems ensue. We generally think that weight gain is the unavoidable consequence of consuming too many calories, with fat cells being the passive recipients of that excess. But fat cells do nothing of consequence without specific instructions—certainly not calorie storage and release, their most critical functions.
Many substances produced in the body or contained in our diet directly affect fat cell behavior, chief among them the hormone insulin. Insulin, made in the pancreas, is widely known for its ability to lower blood sugar.
Problems with the production or action of insulin lead to the common forms of diabetes, specifically type 1 previously called juvenile diabetes and type 2 a frequent complication of obesity. Soon after the start of a meal, insulin level rises, directing incoming calories—glucose from carbohydrate, amino acids from protein, and free fatty acids from the fat in our diet—into body tissues for utilization or storage.
A few hours later, decreasing insulin level allows stored fuels to reenter the blood, for use by the brain and the rest of the body. Although other hormones and biological inputs play supporting roles in this choreography, insulin is the undisputed star.
For example, rats given insulin infusions developed low blood glucose hypoglycemia , ate more, and gained weight. Unsaturated fats, monounsaturated and polyunsaturated should comprise the rest.
Artificial trans fat, or hydrogenated vegetable oil, should be avoided because it has been strongly implicated in heart disease. We hardly expect you to weigh the fat content of your food before you eat it, let alone know which foods are made of what kinds of fat.
So here are some tips:. If not, eat less. We use cookies to improve and personalise your experience.
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