Carbohydrates supply 4 calories per gram and they fuel muscle movement as well as the digestive system and the central nervous system. Are you ready for the cold dark days that come with Daylight Saving Time? Prepare for winter skin before turning your clock back on Sunday. New research suggests that. Counting calories: Get back to weight-loss basics. Your weight is a balancing act, and calories play a big role. Find out how calories determine your weight and ways. Learn all about the nutritional importance of proteins, fats and carbohydrates in our diet, and explore how our bodies use these macronutrients. Metabolic Research Center has been helping people successfully lose weight for over 30 years. Our science based approach makes weight loss easy and effective, and our. Learn About Carbohydrates, Proteins & Fats. Understanding Fats. It all started in the . Doctors, nutritionists and public health officials told us to stop eating so much fat. Cut back on fat, they said, to lose weight and fend off heart disease among other ills. Americans listened, but that didn’t improve our food choices. Rather, low- fat food labels seduced us, and we made pretzels and fat- free, sugar- rich desserts our grocery staples. Today we know to focus on the quality of the fat instead of simply the quantity. Fats in the Body. Say NO to very low- fat diets. ![]() Did you know that your organs, tissues, muscles and hormones are all made from proteins? The protein found in foods is used by every part of the body to develop, grow.Many people find them limiting, boring, tasteless and hard to stick to. And because fat tends to slow down digestion, many low- fat dieters fight hunger pangs all day or eat such an abundance of low- fat foods that their calorie intake is too great for weight loss. Dietary fat has critical roles in the body. Each gram of fat, whether it’s from a spoon of peanut butter or a stick of butter, provides 9 kcals. This caloric density is a lifesaver when food is scarce and is important for anyone unable to consume large amounts of food. The elderly, the sick and others with very poor appetites benefit from high- fat foods. Because their tiny tummies can’t hold big volumes, small children too need fat to provide enough calories for growth. Fats are an energy reserve. Your body can store just small amounts of glucose as glycogen for energy, but you can put away unlimited amounts of energy as fat tissue. This is a problem in our world of excess calories, but was necessary in earlier times when food was scarce. You’ll use this stored energy while you’re sleeping, during periods of low energy intake and during physical activity. Fats provide essential fatty acids (EFA). Fatty acids differ chemically by the length of their carbon chains, the degree of saturation (how many hydrogen atoms are bound to carbon) and the location of carbon- carbon double bonds. These are critical differences that give each fatty acid unique functions. Our bodies are amazing machines capable of producing most of the needed fatty acids. There are two fatty acids that it cannot make at all, however. They are called LA (linoleic acid) and ALA (alpha linolenic acid). This makes LA and ALA . In the body, fatty acids are important constituents of cell membranes, and they are converted to chemical regulators that affect inflammation, blood clotting, blood vessel dilation and more. Clinical deficiencies are rare. A deficiency of LA is usually seen in people with severe malabsorption problems. Its symptoms are poor growth in children, decreased immune function, and a dry, scaly rash. In the few cases of ALA deficiency that doctors and researchers are aware of, the symptoms were visual problems and nerve abnormalities. Fats carry fat- soluble nutrients. Dietary fats dissolve and transport fat- soluble nutrients, such as some vitamins and also disease- fighting phytochemicals like the carotenoids alpha- and beta- carotene and lycopene. To illustrate, researchers were able to detect only negligible amounts of absorbed carotenoids in the blood of individuals who had eaten a tossed salad with fat- free salad dressing. With reduced- fat dressing, the study participants absorbed some carotenoids, but with full- fat dressing, they absorbed even more. You already know that fat makes food taste good. That’s partly because fats dissolve flavorful, volatile chemicals. They also add a rich, creamy texture, giving food a satisfying mouthfeel. Imagine the texture of fat- free chocolate. Not good, probably. Finally, fats provide a tenderness and moistness to baked goods. Fats in the Diet. Fats and oils (collectively known as lipids) contain mixtures of fatty acids. You may refer to olive oil as a monounsaturated fat. Many people do. Really, however, olive oil contains a combination of monounsaturated, saturated and polyunsaturated fatty acids, but it has more monounsaturated fatty acids than other types. Similarly, it is technically incorrect to call lard a saturated fat. It does contain mostly saturated fatty acids, but both monounsaturated and polyunsaturated fatty acids are present as well. There is no Recommended Dietary Allowance (RDA) or Adequate Intake (AI) for total fat intake for any population other than infants. Depending on the age, the AI for infants is 3. The Acceptable Macronutrient Distribution Range (AMDR) is 2. For an adult consuming 1. The AMDR for children is higher and varies by age, starting out at 3. AMDR for adults. Experts discourage low- fat diets for infants, toddlers and young children because fat is energy- dense, making it appropriate for small, finicky appetites and to support growth and the developing central nervous system. The AIs for LA and ALA for adults range from 1. Saturated Fats. Because your body can make all the saturated fatty acids it needs, you do not need any in the diet. High intakes of most saturated fatty acids are linked to high levels of LDL (low- density lipoprotein), or bad, cholesterol and reduced insulin sensitivity. The American Heart Association favors a greater restriction to just 7% of total calories (1. If you tried to eat no saturated fatty acids, however, you would soon find that you had little to eat. Remember that fats are combinations of fatty acids, so even nuts and salmon (good sources of healthy fats) contain some saturated fatty acids. What does bacon grease look like after the pan has cooled? Its firmness is a hint that bacon is high in saturated fat. Many saturated fats are solid at room temperature. Dairy fat and the tropical oils (coconut, palm and palm kernel) are also largely saturated. The greatest sources of saturated fat in the American diet are full- fat cheese, pizza and desserts. Loading up on fat- free pretzels and gummy candies may be tempting, but is a misguided strategy because diets high in heavily refined carbohydrates typically increase triglycerides and lower the beneficial HDL (high- density lipoprotein) cholesterol, both risk factors for heart disease. A better strategy is to replace the foods rich in unhealthy fats with foods rich in healthy fats. Cooking with oils is better than cooking with butter or lard. A quick lunch of a peanut butter sandwich instead of a slice of pizza will do your heart some good. Trading out some of the cheese on your sandwich for a slice or two of avocado is another smart move. If your calories are in excess, switch from whole milk or 2% reduced- fat milk to 1% low- fat milk or nonfat milk to trim both calories and saturated fats. Trans Fats. Food manufacturers create both saturated and trans fats when they harden oil in a process called hydrogenation, usually to increase the shelf life of processed foods like crackers, chips and cookies. Partial hydrogenation converts some, but not all, unsaturated fatty acids to saturated ones. Others remain unsaturated but are changed in chemical structure. These are the health- damaging trans fats. Many experts consider trans fats even worse than saturated fats because, like saturated fats, they contribute to insulin resistance. They also lower HDL cholesterol (the good cholesterol). Achieving this might be trickier than you realize because many foods touting No Trans Fats on their labels actually contain traces of these artery- scarring fats. That’s because the law allows manufacturers’ to claim zero trans fats as long as a single serving contains no more than 0. If you eat a few servings of foods with smidgens of trans fat like margarine crackers and baked goods, you can easily exceed the recommended limit. Identify traces of trans fats by reading the ingredients lists on food labels. Partially hydrogenated oil is code for trans fat. You know that there are at least traces of trans fat present. When oil is fully hydrogenated (the label will say hydrogenated or fully hydrogenated), it will not contain trans fats. Instead, the unsaturated fatty acids have been converted to saturated fatty acids. Unsaturated Fats. As discussed, unsaturated fatty acids improve blood cholesterol levels and insulin sensitivity when they replace saturated and trans fats. There are two classes of unsaturated fatty acids: monounsaturated fats and polyunsaturated fats. Monounsaturated fat souces include avocados, nuts, seeds and olives. Peanut, canola and olive oils are additional sources. There are several types of polyunsaturated fats, and they each have different roles in the body. Omega- 3 fatty acids have been in the spotlight recently because of their role in heart disease prevention. ALA is an omega- 3 fatty acid, and you can find it in walnuts, ground flaxseed, tofu and soybeans, as well as common cooking oils like canola, soybean and walnut oils. Remember that your body is unable to create ALA, so it’s essential to get it in the diet. From ALA, your body makes two other critically important omega- 3 fatty acids (EPA and DHA), but the conversion is very inefficient. It’s better to get EPA and DHA from fish. Not only are EPA and DHA important to the heart, but they also promote visual acuity and brain development in the fetus, infant and child; they seem to slow the rate of cognitive decline in the elderly; and they may decrease the symptoms associated with arthritis, ulcerative colitis and other inflammatory diseases. You will find them in bluefish, herring, lake trout, mackerel, salmon, sardines, and tuna. Omega- 6 fatty acids are a second type of polyunsaturated fats. LA is an omega- 6 fatty acid and has to be acquired through the diet. Sources of omega- 6 fatty acids are sunflower seeds, Brazil nuts, pecans and pine nuts. Some cooking oils are good sources too, such as corn, sunflower, safflower and sesame oils. Otherwise you can expect to loosen your belt as you put on the pounds. Don’t fear fats. Instead choose them wisely, making sure you do not exceed your calorie needs. Enjoy foods with monounsaturated and polyunsaturated fats while limiting the saturated and trans fats.
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