Transcript Vitamin A
Nutritional Chemistry: Vitamins, Carbohydrates, Minerals, and Water Freddie Arocho-Perez Kaplan University SC155: Introduction to Chemistry Elements in the Human Body Vitamins • One of the first discoveries of the importance of vitamins came in the late 1700s. • A Scottish doctor, James Lind, discovered that sailors who were fed citrus fruits recovered from “scurvy”, a disease that killed about a million seamen between 1600 and 1800. Vitamins “Scurvy” causes bleeding and inflamed gums, loose teeth, poor wound healing (purplish spots called “petechiae”), easy bruising, bumps of coiled hair on the arms and legs, pain in the joints, muscle wasting, and many other problems. Scurvy is rarely seen today except in alcoholics who receive their entire calorie intake from alcohol. Today, health scientists know that scurvy is caused by a lack of vitamin C, which is found in abundance in citrus fruits. “Cheeeeeeeeeeeeese!!!” What Are Vitamins? Vitamins are organic (carbon containing) molecules that mainly function as catalysts for reactions within the body. A catalyst is a substance that allows a chemical reaction to occur using less energy and less time than it would take under normal conditions. If these catalysts are missing, as in a vitamin deficiency, normal body functions can break down and make a person susceptible to disease. What Are Vitamins? • Nutrients that are made by living things, are required only in small amounts (hundredths of a gram in many cases), and that assist many chemical reactions in the body are vitamins. • There are two classes of vitamins: • Fat-soluble vitamins: dissolve in fatty material • Water-soluble vitamins: dissolve in water Water-Soluble Vitamins i. Includes Vitamin C, Vitamins B1, B2, B3, B6, B12, Pantothenic acid, Folate, Biotin ii. Water-soluble vitamins cannot be stored in the body. • Sources of water-soluble vitamins are: • fruits • vegetables • whole-grain foods • and many other foods Vitamin C Vitamin C is important to all animals, including humans, because it is vital to the production of collagen. Collagen is the most ubiquitous substance in the body because it is the most abundant of the fibers contained in connective tissue. Connective tissue gives our body form and supports our organs. Vitamin C Vitamin C (Ascorbic Acid) is biologically active without any change in structure from the molecules present in food. Vitamin C is found in citrus fruits, broccoli, and greens. Vitamin C Antioxidants • Vitamins called antioxidants help protect healthy cells from the damage caused by the normal aging process as well as from certain types of cancer. • Antioxidants protect cells from the damaging effects of free radicals, which are molecules that contain an unshared electron. Free radicals damage cells and might contribute to the development of cardiovascular disease and cancer. • Vitamins C and E are two of the most powerful antioxidants. • Vitamin E prevents the breakdown by oxidation of vitamin A and polyunsaturated fats. Vitamin E Vitamin E Fat-Soluble Vitamins i. Includes Vitamins A, D, E, K ii. Fat-soluble vitamins are stored in the body. Dietary fat enhances the absorption of fat-soluble vitamins. • Sources of fat-soluble vitamins are: • vegetable oils • liver • eggs • certain vegetables Vitamin A Vitamin A (Retinol) helps form and maintain healthy teeth, skeletal and soft tissue, mucous membranes, and skin. It is also known as retinol because it produces the pigments in the “retina” of the eye. Vitamin A promotes good vision, especially in low light. It may also be needed for reproduction and breast-feeding. Vitamin A Vitamin A Carbohydrates Simple sugars known as “watered carbons”, indicating one carbon for each water. Your liver breaks down carbohydrates into glucose (blood sugar). Glucose and fructose are the major monosaccharides in our diets. Carbohydrates Minerals • Your body requires only small amounts of minerals, which are nutrients that occur naturally in rocks and soil. • Minerals help your body grow, develop, and stay healthy. Calcium, Ca • Calcium is important in blood clotting and the functioning of your nervous system. • It is an essential ingredient in the formation and maintenance of bones and teeth. • A lack of calcium can sometimes lead to osteoporosis, a condition in which the bones gradually weaken. Sodium, Na • Sodium is important in several body processes, including the functioning of the heart and water balance. • Too much sodium can cause a problem with blood pressure. • Maintains fluid and electrolyte balance, supports muscle contraction, and nerve impulse transmissions. Iron, Fe • Iron is necessary for healthy red blood cells. • If a person’s diet does not include enough iron, he or she may develop anemia, a condition in which the red blood cells do not contain enough hemoglobin. • Iron also helps in energy metabolism. Iron, Fe Hemoglobin Protein. Oxygen binds to the iron in red blood cells. Iron, Fe Potassium, K • Maintains fluid and electrolyte balance, cell integrity, muscle contractions and nerve impulse transmission. • Potassium and sodium work together to maintain water balance in the body. • Sodium and potassium have complementary functions in the body, helping to regulate things like fluid balance and blood pressure. • We need to maintain a precise balance of potassium and sodium in our cells. • Many Americans do not consume enough potassium. Water, H2O • Water is your body’s most important nutrient, is involved in every bodily function. • About 70-75% of your body weight is water. • Nearly all of the body’s chemical reactions, including those that produce energy and build new tissues, take place in a water environment. Water and Homeostasis • Homeostasis is the process of maintaining a steady state inside your body. • When you become overheated, your body excretes perspiration, which cools your body. Thus, water regulates body temperature. • Water contains dissolved substances called electrolytes that regulate many processes in your cells. Preventing Dehydration • Dehydration is a serious reduction in the body’s water content. • Symptoms of dehydration can include weakness, rapid breathing, and a weak heartbeat.