Vitamin E: Tocopherol
Vitamin E benefits the body by acting as an antioxidant, and protecting vitamins A and C, red blood cells, and essential fatty acids from destruction. Research from decades ago suggested that taking antioxidant supplements, vitamin E in particular, might help prevent heart disease and cancer. However, newer findings indicate that people who take antioxidant and vitamin E supplements are not better protected against heart disease and cancer than non-supplement users. Many studies show a link between regularly eating an antioxidant rich diet full of fruits and vegetables, and a lower risk for heart disease, cancer, and several other diseases. Essentially, recent research indicates that to receive the full benefits of antioxidants and phytonutrients in the diet, one should consume these compounds in the form of fruits and vegetables, not as supplements.
Food Sources for Vitamin E
About 60 percent of vitamin E in the diet comes from vegetable oil (soybean, corn, cottonseed, and safflower). This also includes products made with vegetable oil (margarine and salad dressing). Vitamin E sources also include fruits and vegetables, grains, nuts (almonds and hazelnuts), seeds (sunflower) and fortified cereals.
RDA
The Recommended Dietary Allowance (RDA) for vitamin E is based on the most active and usable form called alpha-tocopherol. Food and supplement labels list alpha-tocopherol as the unit International units (IU) not in milligrams (mg). Onemilligram of alpha-tocopherol equals to 1.5 International Units (IU). RDA guidelines state that males and females over the age of 14 should receive 15 mcg of alpha-tocopherol per day. Consuming vitamin E in excess of the RDA does not result in any added benefits.
Vitamin E Deficiency
Vitamin E deficiency is rare. Cases of vitamin E deficiency usually only occur in premature infants and in those unable to absorb fats. Since vegetable oils are good sources of vitamin E, people who excessively reduce their total dietary fatmay not get enough vitamin E.
Vitamin E toxicity
Vitamin E obtained from food usually does not pose a risk for toxicity. Supplemental vitamin E is not recommended due to lack of evidence supporting any added health benefits. Megadoses of supplemental vitamin E may pose a hazard to people taking blood-thinning medications such as Coumadin (also known as warfarin) and those on statin drugs.
VITAMIN K
Vitamin K is naturally produced by the bacteria in the intestines, and plays an essential role in normal blood clotting, promoting bone health, and helping to produce proteins for blood, bones, and kidneys.
Food Sources for Vitamin K
Good food sources of vitamin K are green, leafy-vegetables such as turnip greens, spinach, cauliflower, cabbage and broccoli, and certain vegetables oils including soybean oil, cottonseed oil, canola oil and olive oil. Animal foods, in general, contain limited amounts of vitamin K.
RDA
Males and females age 14 – 18: 75 mcg/day; Males and females age 19 and older: 90 mcg/day
Vitamin K Deficiency
Hemorrhage can occur due to sufficient amounts of vitamin K. Vitamin K deficiency may appear in infants or in people who take anticoagulants, such as Coumadin (warfarin), or antibiotic drugs. Newborn babies lack the intestinal bacteria to produce vitamin K and need a supplement for the first week. Those on anticoagulant drugs (blood thinners) may become vitamin K deficient, but should not change their vitamin K intake without consulting a physician. People taking antibiotics may lack vitamin K temporarily because intestinal bacteria are sometimes killed as a result of long-term use of antibiotics. Also, people with chronic diarrhea may have problems absorbing sufficient amounts of vitamin K through the intestine and should consult their physician to determine if supplementation is necessary.
Vitamin K toxicity
Although no Tolerable Upper Intake Level (UL) has been established for vitamin K, excessive amounts can cause the breakdown of red blood cells and liver damage. People taking blood-thinning drugs or anticoagulants should moderate their intake of foods with vitamin K, because excess vitamin K can alter blood clotting times. Large doses of vitamin K are not advised.
Intext Questions
Fill in the balnks:
1. Vitamins are classified into ………………. and ……………….
2. Vitamin B complex comprises ………………. vitamins in total.
3. Pellagra and Scurvy are caused by ………………. and ………………. deficiency.
4. Water soluble vitamins are excreted through ……………….
5. ………………. can be synthesized by human body.
2. Match the following
1. Vitamin A deficiency (a) Vitamin D
2. Vitamin K (b) Vitamin E
3. Bone formation (c) Vitamin B12
4. Cobalamin (d) Night blindness
5. Tocopherol (e) Coagulation
3. True or false:
1. Vitamins are required in large amounts.
2. Vitamin B2 is otherwise known as Riboflavin.
3. All vitamins are synthesized in our body. (false)
4. Fat malabsorption leads to deficiency of fat soluble vitamins.
5. Water soluble vitamins are stored in our body.
1. The term vitamin is used to describe certain orgain compounds that are needed by the body but they cannot be manufactured by the body.
2. Vitamins serve as catalysts for certain reactions in the body
3. Based on solubility vitamins are classified as either fat soluble or vitamin soluble
4. Vitamins A, D, E and K are fat soluble and vitamins C and B is water soluble
Terminal Questions
1. Name the B complex vitamins.
2. Classification of vitamins.
3. Give the RDA of thiamine, folate, niacin, vitamin C.
4. Name the fat soluble vitamins and where they are stored?
5. What are the symptoms of Pellagra and Scurvy?
Answers To Intext Questions
1. fat soluble and water soluble
2. Eight
3. Niacin and vitamin C
4. urine
5. vitamin D
2. 1. (d) 2. (e) 3. (a) 4. (c) 5. (b) 3. 1. false 2. true 3. false 4. true 5. false
