What are vitamins • Organic molecules needed • for some enzymes to function properly • To act as antioxidants, getting rid of free radicals that can cause DNA mutations • Inorganic molecules, by the way, are minerals
History • 1795, British Navy ships carried a mandatory supply of limes or lime juice to prevent scurvy among the sailors – they were given the name “limeys” • Japanese Navy gave sailors whole grain barley to ward off beriberi • It wasn’t til 1912 that people knew why these “prescriptions” worked to prevent diseases
Vital-amine • Casimir Funk named vitamins – vital amines because they were compounds that contained nitrogen (amines contain nitrogen) and were vital for health • Along with Frederick Hopkins, they came up with the idea that scurvy and beriberi were diseases that resulted from the deficiency of certain compounds that could be found in foods.
Important Vitamins There are 18 vitamins and minerals essential in a healthy diet…but IB only wants you to know detailed info about: • Vitamin A (retinol) • Vitamin C (Ascorbic Acid) • Vitamin D (Calciferol)
Vitamin Classification • Fat-soluble vs Water soluble • Too much of a water soluble vitamin = ok, comes out in urine • Too much of a fat soluble vitamin = sickness because it doesn’t dissolve in your urine readily and gets stored in your body. • Fat soluble vitamins: • All Dogs Eat Kibbles
Vitamin A • Required for the production of rhodopsin (light-sentistive material in the rods of the retina). • Too Little: • Nightblindness • Xeropthalmia –have difficulty producing tears • Effects about 500,000 children in underdeveloped nations • Dry mucous membranes • Too Much: • Makes you think you have a brain tumor • Headache, vomiting, nausea, abnormal vision, loss of hair • Some precursers can make you turn orange =)
Vitamin A Poisoning A bizarre case of extreme vitamin A poisoning was reported by Artic explorers who killed and ate a polar bear. Those who ate the liver became very ill and three of them lost patches of skin. Later, scientists discovered that 0.25 lb of the liver contains 2.5 yrs worth of Vitamin A for humans.
How do we get vitamin A? • 2 Chemicals: Retinoids and carotenoids • Retinoids – body can use right away • Carotenoids – body can change it into a retinoid • Beta-carotene (Why are carrots good for your eyes? Have you ever seen a rabbit with glasses?) • Carotenoids don’t get stored in liver • Foods with 25% of your RDA for Vitamin A • Cearal 1oz, oatmeal 2.3 cups • Fruit: apricots, canteloupe, mango (1/2 c) • Veggies: carrots, kale, peas, sweet peppers (1/2 c cooked) • Meat: Liver 3oz • Milk: 2 cups
Vitamin C • Required for • Production of collagen: the protein of connective tissue. • Antioxidant • Protects immune system, helps fight off infection, reduces allergic reactions • Too Little: • Scurvy(bleeding gums; tooth loss; mosebleeds; bruising; painful or swollen joints; shortness of breath, increased susceptibility to infection, skin rashes; muscle pains, slow wound healing) • Too Much: • More than 1000 mcg may cause upset stomach, diarrhea, or constipation
How do we get Vitamin C? Did you know that many foods are preserved with sodium nitrite to prevent the growth of bacteria. At high T, nitrite + protein forms carcinogen. Vitamin C prevents that rxn so it is added to processed meat, too. • On the label, look for: • Sodium ascorbate • Isoacrobate • Ascorbic acid • Foods with 25% of RDA • Cereal: 1 oz • Meat: Liver 3oz • Fruit: Canteloupe, grapefruit, mango, orange, strawberries, ½ c. • Veggies: Asparagus, broccoli, brussel sprouts, kale, kohlrabi, sweet peppers, snow peas (cooked) ½ c. sweet potato: 1 med.
Vitamin D • Required for the uptake of calcium and phosphorus from food. • Too little: • can cause weak bones (Rickets) in children • In adults: osteomalacia (soft bones, fracture easily) • Too much: • Kidney stones and hard lumps of calcium in muscles and organs • Headache, nausea, vomiting, high blood pressure, retarded physical growth and mental retardation in children, fetal abnormalities
How do we get Vitamin D? • 3 forms • Calciferol: occurs in fish oils, egg yolks • Cholecaliferol: created when sunlight hits skin, reacting with steroids in body fat just underneath skin • Ergocalciferol: found in plants • Foods with 25% of RDA • Salmon or tuna 1.5-2 oz • Eggs: 3 • Milk: 1 cup Some people claim that you should not use sunscreen so that your body can use the sunlight to produce Vitamin D. Most doctors, though, advise getting Vitamin D through your food and wear a high SPF sunscreen at all times.
Fortified Foods • Foods are fortified to provide us with the nutrients we need to stay healthy • Ex: milk is fortified with vitamin D • A pre-curser to vitamin D is extracted from plants, then irradiated to make an active form of Vitamin D, then it is added to food
Cooking and vitamin absorption • Studies show that cooking foods can cause a decrease in the amount of vitamins in the food • Water soluble vitamins dissolve in cooking water • Some vitamins are broken down by heating • Some vitamins, though, are better than no vitamins. So eat your veggies, cooked or not.