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NUTRIENTS AND HEALTH
CARBOHYDRATES –
Monosaccharaide a sugar (like sucrose or fructose) that does not hydrolyze to give other sugars; the simplest group of carbohydrates Simple Carbohydrates Simple carbohydrates are simple sugars with a chemical structure that is composed of one or two sugars. They are refined sugars that have very little nutritional value to the body, and therefore, it's advisable that their consumption be limited to small quantities. In comparison to complex carbohydrates, simple carbohydrates are digested by the body more quickly, because they have a very simple chemical structure. There are two types of simple carbohydrates: monosaccharides and disaccharides. Monosaccharides consist of only one sugar, and examples include fructose, galactose and glucose. Disaccharides consist of two chemically-linked monosaccharides, and they come in the form of lactose, maltose and sucrose. Foods that contain simple carbohydrates include table sugar, products with white flour, honey, milk, yoghurt, candy, chocolate, fruit, fruit juice, cake, jam, biscuits, molasses, soda and packaged cereals. Despite the fact that simple carbohydrates do not contain enough essential nutrients, some foodstuffs such as fruits may still be good for you. Complex Carbohydrates Complex carbohydrates consist of a chemical structure that is made up of three or more sugars, which are usually linked together to form a chain. These sugars are mostly rich in fiber, vitamins and minerals. Due to their complexity, they take a little longer to digest, and they don't raise the sugar levels in the blood as quickly as simple carbohydrates. Complex carbohydrates act as the body's fuel, and they contribute significantly to energy production. Similar to simple carbohydrates, complex carbohydrates are divided into two categories: oligosaccharides and polysaccharides. Oligosaccharides consist of a small number of monosaccharaides, which does not exceed 10. They are important in the absorption of certain
minerals and the formation of fatty acids. Polysaccharides are often made up of a large number of monosaccharides and disaccharides. Examples of polysaccharides include cellulose, dextrin, glycogen and starch. Complex carbohydrates are commonly found in vegetables, whole-meal bread and cereals. Examples of foods that contain complex carbohydrates include spinach, yams, broccoli, beans, zucchini, lentils, skimmed milk, whole grains and many other leguminous plants and vegetables. Complex carbohydrates have a higher nutritional value than simple carbohydrates. It may be confusing to differentiate simple and complex carbohydrates due to the fact that complex ones contain certain elements of simple ones. Nevertheless, differentiating the two should not be a problem since their chemical structures are very different, and therefore, they can be distinguished by their nutritional properties. The consumption of simple carbohydrates is not recommended, especially for diabetics. Functions of carbohydrates Carbohydrates have a variety of functions in the animal organism; the most important is to supply energy for the body functions. Even though fat yields more energy per unit body weight than carbohydrate (9 calories per gram, as compared to 4 calories per gram), the intake of carbohydrate is greater than fat in the normal diet. The functions of carbohydrates are discussed below:
1. As a source of energy: The main function of carbohydrate is to supply energy for the body processes. A greater part of the energy in the diet (more than 50-80%) is supplied by carbohydrates. Some of the carbohydrates are immediately utilized by the tissues and the remaining is stored as glycogen in the liver and muscles and some are stored as adipose tissues for future energy needs. 2. Protein-sparing action: Carbohydrates are mainly utilized by the body of fulfilling the major part of the energy needs, thus sparing protein for tissue building and repairing. The first physiological demand of the body is the need for energy, which must be satisfied before the nutrients are used for other functions. So, this function of carbohydrates to spare protein for its primary purpose of body building and repair of tissues is an important one.
- Improved bowel regularity Reduced intestinal infections Relief for inflammatory bowel disease Probiotics Probiotics are micro-organisms that have claimed health benefits when consumed. Lactic acid bacteria (LAB) and bifidobacteria are the most common types of microbes used as probiotics, but certain yeasts and bacilli may also be used. Probiotics are commonly consumed as part of fermented foods with specially added active live cultures, such as in yogurt, soy yogurt, or as dietary supplements. When a person takes antibiotics, both the harmful bacteria and the beneficial bacteria are killed. A reduction of beneficial bacteria can lead to digestive problems, such as diarrhea, yeast infections and urinary tract infections. The possibility that supplemental probiotics affect such digestive issues is unknown, and remains under study. Advantages of probiotics
- Probiotics can improve intestinal function and maintain the integrity of the lining of the intestines
- There’s also evidence that probiotics help maintain a strong immune system.
- Treating childhood diarrhea
- Preventing antibiotic-associated diarrhea and infectious diarrhea
- Preventing pouchitis, an inflammation of the intestines that can follow intestinal surgery PREBIOTIC VS PROBIOTIC PREBIOTICS PROBIOTICS PREBIOTICS are a special form of dietary fiber PROBIOTICS are live bacteria in yogurt, dairy products and pills. There are hundreds of probiotic species available. Which of the hundreds of available probiotics is best is still unknown. PREBIOTIC powders are not affected by heat, cold, acid or time. PROBIOTIC bacteria must be kept alive. They may be killed by heat, stomach acid or simply die with time. PREBIOTICS provide a wide range of health benefits to the otherwise healthy person. Most of these have been medically proven. PROBIOTICS are still not clearly known to provide health benefits to the otherwise healthy. Some are suspected but still not proven. PREBIOTICS nourish the good bacteria that everyone already has in their gut. PROBIOTICS must compete with the over 1000 bacteria species already in the gut. PREBIOTICS may be helpful or preventative for irritable bowel (IBS), or inflammatory bowel disease (Crohn’s Disease, Ulcerative Colitis), colon polyps and cancer and those people with a leaky gut. Certain PROBIOTIC species have been shown to be helpful for irritable bowel disease and for recurrence of certain bowel infections such as C. difficile.
PROTEINS
Proteins are essential nutrients for the human body. They are one of the building blocks of body tissue, and can also serve as a fuel source. As a fuel, proteins contain 4 kcal per gram, just like carbohydrates and unlike lipids, which contain 9 kcal per gram. Proteins are polymer chains made of amino acids linked together by peptide bonds. During human digestion, proteins are broken down in the stomach to smaller polypeptide chains via hydrochloric acid and protease actions. This is crucial for the synthesis of the essential amino acids that cannot be biosynthesized by the body. Amino acids can be divided into three categories: essential amino acids, non-essential amino acids, and conditional amino acids. Essential amino acids cannot be made by the body, and must be supplied by food. Non-essential amino acids are made by the body from essential amino acids or in the normal breakdown of proteins. Conditional amino acids are usually not essential, except in times of illness, stress, or for someone challenged with a lifelong medical condition Protein can be found in a wide range of food. The best combination of protein sources depends on the region of the world, access, cost, amino acid types and nutrition balance, as well as acquired tastes. Some foods are high in certain amino acids, but their digestibility and the anti- nutritional factors present in these foods make them of limited value in human nutrition. Therefore, one must consider digestibility and secondary nutrition profile such as calories, cholesterol, vitamins and essential mineral density of the protein source.[6]^ On a worldwide basis, plant protein foods contribute over 60 percent of the per capita supply of protein, on average. In North America, animal-derived foods contribute about 70 percent of protein sources. Meat, eggs and fish are sources of complete protein. Milk and milk-derived foods are also good sources of protein. Complete Proteins A complete protein contains an adequate amount of all of the essential amino acids that should be incorporated into a diet. Some protein contains all the amino acids needed to build new proteins, which generally come from animal and fish products. A complete protein must not lack even one essential amino acid in order to be considered complete. Sources of Complete Proteins The following foods are examples of complete proteins, which need not be combined with any other food to provide adequate protein: Meat Fish Poultry
Grains with Dairy - sample meal: white cheddar and whole wheat pasta. Dairy with Seeds - sample meal: yogurt mixed with sesame and flax seeds. Legumes with Seeds - sample meal: spinach salad with sesame seed and almond salad dressing. FUNCTIONS OF PROTEINS Protein is an important substance found in every cell in the human body. In fact, except for water, protein is the most abundant substance in your body. This protein is manufactured by your body utilizing the dietary protein you consume. It is used in many vital processes and thus needs to be consistently replaced. You can accomplish this by regularly consuming foods that contain protein. Repair and Maintenance Protein is termed the building block of the body. It is called this because protein is vital in the maintenance of body tissue, including development and repair. Hair, skin, eyes, muscles and organs are all made from protein. This is why children need more protein per pound of body weight than adults; they are growing and developing new protein tissue. Energy Protein is a major source of energy. If you consume more protein than you need for body tissue maintenance and other necessary functions, your body will use it for energy. If it is not needed due to sufficient intake of other energy sources such as carbohydrates, the protein will be used to create fat and becomes part of fat cells. Hormones Protein is involved in the creation of some hormones. These substances help control body functions that involve the interaction of several organs. Insulin, a small protein, is an example of a hormone that regulates blood sugar. It involves the interaction of organs such as the pancreas and the liver. Secretin, is another example of a protein hormone. This substance assists in the digestive process by stimulating the pancreas and the intestine to create necessary digestive juices. Enzymes Enzymes are proteins that increase the rate of chemical reactions in the body. In fact, most of the necessary chemical reactions in the body would not efficiently proceed without enzymes. For example, one type of enzyme functions as an aid in digesting large protein, carbohydrate and fat molecules into smaller molecules, while another assists the creation of DNA. Transportation and Storage of Molecules
Protein is a major element in transportation of certain molecules. For example, hemoglobin is a protein that transports oxygen throughout the body. Protein is also sometimes used to store certain molecules. Ferritin is an example of a protein that combines with iron for storage in the liver. Antibodies Protein forms antibodies that help prevent infection, illness and disease. These proteins identify and assist in destroying antigens such as bacteria and viruses. They often work in conjunction with the other immune system cells. For example, these antibodies identify and then surround antigens in order to keep them contained until they can be destroyed by white blood cells. FATS (LIPIDS) Lipid is the chemical name for group of compound that includes fats, oils, cholesterol and triglycerides. Fats and oils are the most abundant lipid which is found in plants and animals. Lipid which is solid at room temperature is called fat Lipid which is liquid at room temperature is called oil. Fats are more concentrated form of energy than carbohydrates. They are found in adipose tissues of animal. An ingested fat undergoes emulsification, digestion and absorption. In the presence of adequate supply of carbohydrates fat is stored in fatty tissue.
What are Fats? According to nutrition facts, fats are an essential part of the diet and play an important role in maintaining a healthy life. Fats and cholesterol tend to be the most focused terms of the public and health enthusiasts. There is a valid reason behind this. Fat happens to be the most concentrated source of energy in the diet that providing about 8 to 9 calories per gram, while on the other hand,\ carbohydrates and proteins have only four calories per gram. Fat is known to have three elements which include carbon, hydrogen, and oxygen. But, it has more carbon and hydrogen than oxygen, leading to nine calories per gram. Fats are the source of energy in food, belong to a group of elements called lipids, and they are all combinations of saturated and unsaturated fats. The human body is well designed, which makes up two types of fats, essential for the proper functioning of the body and are obtained from the food consumed. These fats play a major role in
Saturated Fatty Acids present in some food items – Fatty Acids Food Source Acetic acid Vinegar Butyric acid Butter Caproic acid Butter Lauric acid Palm kernel, Coconut Myristic acid Coconut, Butter Palmitic acid Palm, Soya, Sesame, Cotton seed, Butter, Lard Stearic acid Beef, Tallow, Cocoa Butter, Lard Caprylic acid Coconut, Palm kernel CHOLESTEROL –
- Eating foods high in fats, especially saturated fats may increase the level of cholesterol , a waxy, fat-like substance produced by body.
- Cholesterol is part of cell membranes and nerve tissues. It is used by body to form vitamin D and other hormones. It is found only in foods that come from animals, such as butter, eggs, and meats. It is not an essential nutrient because the body produces cholesterol in liver.
- As cholesterol levels in the body increase, the risk of heart and artery diseases increase. Some of the cholesterol tends to be deposited on the walls of the arteries, thereby reducing the flow of blood to the cells supplied by those arteries.
LDL and HDL are two types of cholesterol that are carried in the blood by lipoproteins, a combination of fat and protein: LDL (low-density lipoprotein) Also known as "bad" cholesterol, LDL cholesterol can build up in the walls of your arteries, making them narrow and hard. High levels of LDL cholesterol can increase your risk of stroke and heart disease. HDL (high-density lipoprotein) Also known as "good" cholesterol, HDL cholesterol absorbs excess cholesterol from the blood and carries it back to the liver, which then removes it from the body. High levels of HDL cholesterol can lower your risk of stroke and heart disease. To maintain healthy cholesterol levels, you can: Eat a heart-healthy diet that's low in saturated and Trans-fats, Exercise regularly, maintain a healthy weight, and quit smoking. A cholesterol test can measure your LDL, HDL, and total cholesterol levels. Most healthy adults should get their cholesterol checked every 4–6 years. Ghee Desi ghee, or clarified butter, is a traditional ingredient in Indian cooking and has been used in Ayurvedic medicine for centuries. While it is indeed high in saturated fat, it can offer several health benefits when consumed in moderation: Ghee has many health benefits, including :
- Gut health: The short-chain fatty acids in ghee can keep your gut healthy.
- Heart health: Ghee is rich in short- and medium-chain fatty acids, which are good for your heart.
- Skin and hair care: Ghee can be applied topically to moisturize and nourish the skin and hair.
- Oral hygiene: Ghee can be used for oil pulling, an Ayurvedic practice that involves swishing a tablespoon of ghee in your mouth to improve oral hygiene. There are many myths about ghee, including that it's unhealthy, fattening, and not suitable for people who are lactose intolerant:
- Myth: Ghee is unhealthy:
- Fact: Ghee is actually a source of healthy fats, including omega-3 fatty acids, which can be good for heart health.
Types of Unsaturated Fats There are two main types of unsaturated fats:
1. Monounsaturated Fats Monounsaturated fats have been shown to help: Improve cholesterol levels by increasing good cholesterol (HDL) and reducing bad cholesterol (LDL). Lower the risk of cardiovascular diseases, such as heart disease and stroke. Help with controlling blood sugar and insulin levels, particularly beneficial for individuals with type 2 diabetes. Foods rich in monounsaturated fats include: Olive oil Peanut oil Canola oil Avocados Most nuts (almonds, peanuts, cashews) Most seeds (pumpkin, sunflower, sesame) 2. Polyunsaturated Fats Polyunsaturated fats are essential because the body cannot produce them, so they must be obtained through the diet. These fats are vital for: Muscle movement Blood clotting Reducing inflammation Supporting heart health Polyunsaturated fats are divided into two key types: omega-3 and omega-6 fatty acids. Omega-3 Fatty Acids Omega-3s are crucial for heart health and have anti-inflammatory properties. They can help: Lower triglycerides Reduce blood pressure Decrease the risk of heart disease and stroke Improve brain function and cognitive development
Rich sources of omega-3 fatty acids include: Fatty fish: sardines, tuna, salmon, trout, mackerel, herring Ground flaxseeds and flaxseed oil Non-hydrogenated soybean oil Walnuts and chia seeds Canola oil Omega-6 Fatty Acids Omega-6 fatty acids also contribute to heart health, although there is ongoing debate about their potential pro-inflammatory effects. When consumed in the right balance with omega-3s, omega- 6s can help: Protect against cardiovascular disease Support brain function and growth Sources of omega-6 fatty acids include: Safflower oil Soybean oil Sunflower oil Corn oil Walnut oil Balance Between Omega-3 and Omega- The modern diet tends to have an imbalance between omega-3 and omega-6 fatty acids, often favouring omega-6. It’s important to maintain a healthy ratio between these two to avoid potential inflammatory effects associated with an excess of omega-6s. Risks of Repeatedly Heating Oils Research has shown that repeatedly heating oils, particularly at high temperatures, can degrade their beneficial antioxidant properties and increase the production of harmful free radicals. Free radicals can cause oxidative stress, which has been linked to various chronic diseases such as cancer and cardiovascular diseases. To preserve the health benefits of unsaturated fats: Avoid overheating or burning oils Use oils with higher smoke points (e.g., avocado or refined olive oil) for cooking at higher temperatures Consider using extra virgin olive oil and flaxseed oil for dressings and low-heat cooking By carefully choosing the right types of unsaturated fats and using proper cooking methods, you can enhance their positive impact on health while minimizing potential risks.
Alpha-linolenic acid (ALA): An omega-3 fatty acid Eicosapentaenoic acid (EPA): An omega-3 fatty acid Docosahexaenoic acid (DHA): An omega-3 fatty acid EFAs are found in plant and fish oils, and in animal products like eggs and liver. Fish are a particularly rich source of EFAs, and oily fish like salmon, sardines, and tuna are high in DHA and EPA. A deficiency in EFAs can cause a number of health issues, including: Dry, scaly skin Hair loss Poor wound healing Failure of growth Increased metabolic rate Functions
1. As a source of energy and energy reserve: Fat serves as a concentrated source of energy. Each gram of fat yields 9 calories of energy (twice the double amount yielded by carbohydrates and protein). Any excess of energy is stored in the form of fat or adipose tissue. Adipose tissue which consists mainly of triglycerides is stored under the skin, around the organs and in the abdominal Cavity. 2. Satiety Value: Fat tends to leave the stomach relatively slowly, being released approximately 3Vz hours after ingestion or taking of food. This delay in the emptying time of the stomach helps to delay the onset of hunger pangs and contribute to a feeling of satiety after a meal. 3. Carrier of fat-soluble vitamins: Fat carries fat-soluble vitamins like A, D, E, and K into the body and help in the absorption of these vitamins. 4. Source of essential fatty acids: The body cannot synthesize certain fatty acids and has to be supplied from the diet. These are called as the essential fatty acids linoleic acid, a poly unsaturated fatty acid, which is necessary for the growth of the young and maintenance of a healthy skin. 5. Palatability:
Fat contributes a lot to the palatability of food as appreciated by those who exist on a low-fat diet. Many substances responsible for the flavors and aroma of food are fat soluble. It has also been suggested that fat in the diet stimulates the flow of digestive juices.
6. Insulation: Deposits of fat beneath the skin serve as insulating material for the body, protecting it against shock from changes in environmental temperature. 7. Body regulator: Fat as an essential constituent of the membrane of each individual cell, helps to regulate the uptake and excretion of nutrients by the cell. 8. Protection of vital body Organs: Fat deposits that surround certain vital organs serve to hold them in position and shield them from physical shock and injury to the kidneys and heart are protected in this way. VITAMINS A vitamin (US /ˈvaɪtəmɪn/ or UK /ˈvɪtəmɪn/) is an organic compound required by an organism as a vital nutrient in limited amounts.[1]^ An organic chemical compound (or related set of compounds) is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on the circumstances and on the particular organism. For example, ascorbic acid (vitamin C) is a vitamin for humans, but not for most other animals. Supplementation is important for the treatment of certain health problems but there is little evidence of benefit when used by those who are otherwise healthy Vitamin Sources Functions in Body Signs of Toxicity Signs of deficiency Vitamin A Orange, yellow, green vegetables, liver, margarine, and egg yolk Maintains healthy eyes, skin, bone growth and tooth development, possible aid in cancer protection Nausea, vomiting, dry skin, rashes, hair loss, headache, fatigue Night blindness, eye-infections, rough skin, respiratory infections Vitamin D Milk, eggs, liver, Promotes Loss of appetite, Rickets (poor bone
Minerals are used to regulate a wide range of body processes, from bone formation to blood clotting, and they are important for the body structure. The minerals in our diet are essential for a variety of bodily functions. They are important for building strong bones and teeth, blood, skin, hair, nerve function, muscle and for metabolic processes such as those that turn the food we eat into energy. This means that minerals are needed for the body to work properly, for growth and development, and overall, for maintaining normal health. Different minerals are required in different amounts but they are all essential. Minerals are grouped depending on how much they are needed on a daily basis so the minerals that are needed more in bigger amounts on a daily basis are known as the minerals, macro-minerals or major minerals. The minerals that are needed less and in smaller amounts are known as micro-minerals or trace elements. Children, pregnant/breastfeeding mothers and older people may need to adjust their intake depending on the type of mineral. It is also important to note that excessively high intakes of minerals can be toxic (harmful). Most minerals are either quickly used or lost in waste products, therefore we must eat mineral- rich foods daily to replenish our supply. Iron is an exception –it tends to be kept and recycled by the body, except when there is a blood loss. FUNCTIONS OF MINERALS Bone and Teeth Health Your skeleton provides motility, protection and support for the body. It also stores minerals and other nutrients. Though they appear hard and unyielding, your bones are actually constantly being reabsorbed and reformed by your body. Several minerals make up the lattice architecture of your bones. Calcium is the most abundant mineral in your body and is found in your bones and blood. Along with the minerals phosphorus and magnesium, calcium gives your bones strength and density. This mineral also builds and maintains strong, healthy teeth. BBC Health reports that a calcium deficiency due to poor nutrition or illness can lead to osteoporosis, a condition in which the bones become brittle and less dense, increasing the risk of fractures. KidsHealth notes that foods that are rich in calcium include milk and other dairy products, green, leafy vegetables and canned fish with bones. Energy Production You require oxygen to produce energy that is necessary for every bodily function and process. Red blood cells -- or erythrocytes -- carry oxygen to each of your infinite cells, where it is used to generate energy. Red blood cells contain a heme or iron component that binds to oxygen so that it can be transported. The University of Maryland Medical Center notes that without the iron
molecules, oxygen could not be attached to the blood cells and the body would not be able to produce the energy necessary for life. Iron is an essential mineral, and failing to get enough from your diet can lead to a condition called anemia, which causes weakness and fatigue. This mineral is primarily found in the blood, and it is also stored in your liver, spleen, bone marrow and muscles. Nerve and Muscle Function Potassium is found in bananas, dates, tomatoes, green leafy vegetables, citrus fruits and legumes such as peas and lentils. According to KidsHealth, this nutrient is important to keep muscles and the nervous system functioning normally. Potassium helps to maintain the correct water balance in the cells of your nerves and muscles. Without this essential mineral, your nerves could not generate an impulse to signal your body to move, and the muscles in your heart, organs and body would not be able to contract and flex. Immune Health Some minerals such as calcium are needed in large quantities, while others such as zinc are only needed in trace amounts. Zinc is an essential mineral that is important for keeping your immune system strong and helps your body fight infections, heal wounds and repair cells. KidsHealth notes that eating meat and legumes such as beans, peas and lentils will give you sufficient amounts of zinc. According to BBC Health, the mineral selenium is also needed in small amounts for immune health. A deficiency of selenium has been linked to an increased risk of heart disease and even some types of cancers. WATER
- Water is found in every cell, in the spaces around the cells, in the fluid tissues of the body, and in body cavities
- Water carries dissolved nutrients throughout our body and assists in all of its functions such as: digesting foods, removing wastes, regulating temperature, and cushioning sensitive parts of our body.
- Each day we lose two to three quarts of water and if this water is not replaced the body can dehydrate.
- When minerals are dissolved, they break apart into ions. The ions formed in body fluids are called electrolytes. These ions play a central role in water balance in the body. Water in our bodies The human body can last weeks without food, but only days without water. The body is made up of 55 to 75 per cent water. Water forms the basis of blood, digestive juices, urine and perspiration and is contained in lean muscle, fat and bones.
