Fat and its functionMonika singh141331M.Sc.

Introduction FATis a nutrientis a source of energyadds taste and texture to foodsmakes us feel full longerhelps absorb fat-soluble vitamins

*Sometimes we hear about fat and all the negative aspects like a high fat diet can increase the risk of heart disease.Although true, we often forget that fat is an important nutrient in our diet we need it for normal body functions.Some fats are essential; meaning, we need to eat them because our body cannot make these fats.

Fat:is a nutrientprovides us with energyadds a wonderful taste and texture to foodsmakes us feel full longer because we digest fat more slowly than other nutrientshelps us absorb fat-soluble vitamins like vitamin A, vitamin D, vitamin E, and vitamin K.

Classification Lipids are broadly classified into simple, complex and derived, which are further subdivided into different groups.1. simple lipid: these are esters of fatty acids with various alcohols.(a)fats and oils(b)waxes

2.compound/complex lipid: esters of fatty acids containing groups in addition to an alcohol and a fatty acid.a)phospholipids(b)glycolipids(c)lipoproteins: (d)other complex lipids

3. precursor and derived lipids: these include fatty acids ,glycerol, steroids, other alcohols, fatty aldehydes, and ketone bodies, hydrocarbones, lipid-soluble vitamins and hormones.

Types of FatTypes of fats include: Polyunsaturated fats (PUFA)Monounsaturated fats (MUFA)Saturated fats (SFA)Trans fats (TFA)

*Fat is made up of different fatty acids the building blocks of fat. All fat-containing food has a mixture of these different fatty acids. Usually the type of fat that is in greatest quantity determines how that food is identified. For example, olive oil has more monounsaturated fat than the other fats.The main types of fat are polyunsaturated fat, monounsaturated fat, and saturated fat. We will also talk about trans fats since they are present in a number of foods and are linked to heart disease. However, recently, the food industry has been trying to decrease the amount of trans fat in their products.

Polyunsaturated FatsSome are essential because the body cannot make them: Omega-3 fats can help decrease the risk of heart disease Omega-3 fats are found in fish, flaxseed and omega-3 eggsOther foods with PUFA arevegetable oils (corn, soybean, sunflower), margarines made with vegetable oils, walnuts, sunflower seeds, sesame seeds

*Polyunsaturated fats are an important part of our diet.Some are essential because our body cannot make them like omega-3 fats, which have been shown to reduce the risk of heart disease.Omega-3 fats are found in fish such as salmon, mackerel, albacore tuna, herring and halibut, flaxseed and products with added omega-3 (e.g., eggs, bread, pork).Other sources of PUFA include vegetable oils (corn, soybean, sunflower), margarines made with vegetable oils, walnuts, sunflower seeds, sesame seeds, and flaxseed.The Food Guide recommends a small amount (30-45 mL or 6-9 tsp) of unsaturated fat each day.

Notes to leader:These foods are listed in the Canadian Nutrient File.Their fat profile indicates that the level of PUFA is higher than the other types of fat.

Monounsaturated FatsConsidered good fats because they help decrease the risk of heart diseaseExamples: Olive oil, canola oil, margarine made with canola, peanuts, nuts (almonds, cashews, hazelnuts, pecans)

*Like polyunsaturated fats, monounsaturated fats are considered good fats because they help decrease the risk of heart disease.Foods that are sources of monounsaturated fats include olive oil, canola oil, margarine made with canola, peanuts (and peanut butter), nuts (almonds, cashews, hazelnuts, pistachios, pecans), and avocados.Interestingly, many animal products are identified as primarily sources of saturated fats; however, many cuts of meat, including beef, pork, chicken and fish are higher in monounsaturated fat than saturated fat.For example, lean beef has about 51% monounsaturated fat, 45% saturated fat and 4% polyunsaturated fat.

Note to leaders: Source of information is the Canadian Nutrient File.

Saturated FatsDiets high in saturated fats can increase the risk of heart diseaseExamples: butter, cakes and pastries, chocolate bars, coconut, coffee whitener are all high in saturated fatOther sources of saturated fat include untrimmed meat and higher fat dairy products (e.g., cheese, cream)

*A high intake of total fat and saturated fat has been associated with an increased risk of heart disease.Sources: Food items such as butter, cakes and pastries, chocolate bars, coconut, coffee whitener are all sources of saturated fat.Untrimmed meat and higher fat dairy products are also sources of saturated fat in our diets.

Note to leadersMany animal products are identified as primarily sources of saturated fats. If the meat is untrimmed then the amount of saturated fat is higher than the other fats. However, when trimmed, many cuts of meat, including beef, pork, chicken and fish are lower in total and saturated fat, and higher in monounsaturated fat.For example, lean beef has about 51% monounsaturated fat, 45% saturated fat and 4% polyunsaturated fat.In addition, one-third of the saturated fat in beef is stearic acid, which does not affect blood cholesterol.Source of information is the Canadian Nutrient File.

Trans FatsAre made from hydrogenationThis makes oils more firm.Act like saturated fats in the bodyMost found in commercially prepared foods some French fries, potato chips, donuts, cookies, crackers, cereals, shortening, muffins, pizza crusts, buns, cakes

*Most trans fats are produced through the processing of other polyunsaturated fats this is called hydrogenation.Hydrogenation makes the vegetable oil more stable and firm this results in products that are more suitable than liquid oils for cooking and baking.The problem with these trans fat is that they act like saturated fat increasing the risk of heart disease. The Nutrition Facts Table identifies the amount of trans fat in the packaged product.Most are found in commercially prepared foods some brands of French fries, potato chips, donuts, cookies, crackers, cereals, shortening, muffins, pizza crusts, hamburger buns, cakes (Reference: Heart Headlines, Volume 7(2), Summer 2000. www.becelcanada.com)Many companies are changing their recipes to decrease or eliminate the trans fat in their foods.

Note to leaders Trans fats are produced from partial hydrogenation. Oils that are fully hydrogenated are saturated fats and do not contain trans fats. Unfortunately, both partially hydrogenated oils and fully hydrogenated oils are often listed the same way on labels as hydrogenated oils.

CholesterolCholesterol- a fatlike substance found in every cell in the body. It serves several important functions Part of skin tissue Aids in transport of fatty acids in body Body also needs this to produce hormones

Functions of Fat in the bod

Essential constituent of the membrane of every cell Energy reserve Regulator of body functioninsulatorprotector

Functions of Fat in diet

Source of energySatiety valueCarrier fat soluble vitaminPalatabilityAppearanceFlavorHeat Transfer

ShorteningSolubilityTexture

*Sometimes we hear about fat and all the negative aspects like a high fat diet can increase the risk of heart disease.Although true, we often forget that fat is an important nutrient in our diet we need it for normal body functions.Some fats are essential; meaning, we need to eat them because our body cannot make these fats.

Fat:is a nutrientprovides us with energyadds a wonderful taste and texture to foodsmakes us feel full longer because we digest fat more slowly than other nutrientshelps us absorb fat-soluble vitamins like vitamin A, vitamin D, vitamin E, and vitamin K.

*Fat is made up of different fatty acids the building blocks of fat. All fat-containing food has a mixture of these different fatty acids. Usually the type of fat that is in greatest quantity determines how that food is identified. For example, olive oil has more monounsaturated fat than the other fats.The main types of fat are polyunsaturated fat, monounsaturated fat, and saturated fat. We will also talk about trans fats since they are present in a number of foods and are linked to heart disease. However, recently, the food industry has been trying to decrease the amount of trans fat in their products.

*Polyunsaturated fats are an important part of our diet.Some are essential because our body cannot make them like omega-3 fats, which have been shown to reduce the risk of heart disease.Omega-3 fats are found in fish such as salmon, mackerel, albacore tuna, herring and halibut, flaxseed and products with added omega-3 (e.g., eggs, bread, pork).Other sources of PUFA include vegetable oils (corn, soybean, sunflower), margarines made with vegetable oils, walnuts, sunflower seeds, sesame seeds, and flaxseed.The Food Guide recommends a small amount (30-45 mL or 6-9 tsp) of unsaturated fat each day.

Notes to leader:These foods are listed in the Canadian Nutrient File.Their fat profile indicates that the level of PUFA is higher than the other types of fat.

*Like polyunsaturated fats, monounsaturated fats are considered good fats because they help decrease the risk of heart disease.Foods that are sources of monounsaturated fats include olive oil, canola oil, margarine made with canola, peanuts (and peanut butter), nuts (almonds, cashews, hazelnuts, pistachios, pecans), and avocados.Interestingly, many animal products are identified as primarily sources of saturated fats; however, many cuts of meat, including beef, pork, chicken and fish are higher in monounsaturated fat than saturated fat.For example, lean beef has about 51% monounsaturated fat, 45% saturated fat and 4% polyunsaturated fat.

Note to leaders: Source of information is the Canadian Nutrient File.

*A high intake of total fat and saturated fat has been associated with an increased risk of heart disease.Sources: Food items such as butter, cakes and pastries, chocolate bars, coconut, coffee whitener are all sources of saturated fat.Untrimmed meat and higher fat dairy products are also sources of saturated fat in our diets.

Note to leadersMany animal products are identified as primarily sources of saturated fats. If the meat is untrimmed then the amount of saturated fat is higher than the other fats. However, when trimmed, many cuts of meat, including beef, pork, chicken and fish are lower in total and saturated fat, and higher in monounsaturated fat.For example, lean beef has about 51% monounsaturated fat, 45% saturated fat and 4% polyunsaturated fat.In addition, one-third of the saturated fat in beef is stearic acid, which does not affect blood cholesterol.Source of information is the Canadian Nutrient File.

*Most trans fats are produced through the processing of other polyunsaturated fats this is called hydrogenation.Hydrogenation makes the vegetable oil more stable and firm this results in products that are more suitable than liquid oils for cooking and baking.The problem with these trans fat is that they act like saturated fat increasing the risk of heart disease. The Nutrition Facts Table identifies the amount of trans fat in the packaged product.Most are found in commercially prepared foods some brands of French fries, potato chips, donuts, cookies, crackers, cereals, shortening, muffins, pizza crusts, hamburger buns, cakes (Reference: Heart Headlines, Volume 7(2), Summer 2000. www.becelcanada.com)Many companies are changing their recipes to decrease or eliminate the trans fat in their foods.

Note to leaders Trans fats are produced from partial hydrogenation. Oils that are fully hydrogenated are saturated fats and do not contain trans fats. Unfortunately, both partially hydrogenated oils and fully hydrogenated oils are often listed the same way on labels as hydrogenated oils.