Quiz 61: Vitamins and Minerals
Vitamin D consists of a group of fat-soluble steroids (vitamin D- calciferol, vitamin D2- ergocalciferol, vitamin D3- cholecalciferol) that promote intestinal absorption of minerals such as calcium, magnesium, phosphates and zinc. This vitamin plays a vital role in calcium metabolism and homeostasis. During vitamin D deficiency, blood calcium levels decrease, which triggers parathyroid gland to release parathyroid hormones. When the blood calcium levels fall below the normal, parathyroid gland gets stimulated and releases high levels of parathyroid hormone (PTH). The released PTH stimulates the opens the calcium channels in the kidneys, thereby increasing calcium ion reabsorption. In addition, PTH stimulates kidneys to increase the activity of 1-hyroxylase enzyme to activate 25 (OH)-D to 1, 25 (OH) 2 D. As a result, reabsorption of calcium ions increases in the kidneys. Thus, Jerrod's high calcium levels are may be because of vitamin D deficiency. In contrast, the high blood calcium levels and low vitamin D levels may indicate the tumors of parathyroid gland.
Warfarin and vitamin K are structural analogues and antagonistic in their functions. Warfarin is an anti-coagulant drug, while vitamin K is essential for the synthesis of coagulant proteins by the liver. Administration of vitamin K 1 promotes the synthesis of blood clotting factors by the liver. This reverses the anticoagulant effects of warfarin.
Vitamins are the macronutrients required by the body, which are necessary to be taken through diet. There are two types of vitamins present in our body namely water soluble and fat soluble proteins. Vitamins B complex and vitamin C are water soluble vitamins and vitamins A, D, E and K are fat soluble vitamins. Intake of vitamins in the form of supplements is not suggested because the abnormal levels of vitamins cause a pathological condition called "hypervitaminosis." This condition occurs with fat soluble vitamins. Charlene must be assessed for the following indications for the vitamin therapy: • Eating less than two meals per a day • History of cardiovascular diseases, allergies, hepatic or renal disease • Frequently practicing dieting and you are under weight • Having three or more drinks of alcohol a day • Eating restricted diet with fewer than 5 servings of fruits and vegetables a day • Women of child bearing age or pregnant women • An adult more than 50 years • Suffering from decreased immune functioning and fatigue • Taking more than 3 prescribed or OTC medicines a day