Vitamins are a group of organic food substances or nutrients found only
in living things, plants and animals. They are needed to maintain normal
body functions. The body cannot synthesize its own vitamins so we must
get our vitamins from the foods we eat, or from dietary supplements. Vitamins
are essential for metabolism, growth, and physical well-being.
To put it plainly, if we did not consume adequate amounts of vitamins our bodies would not be able to function properly. Vitamins are essential to so many processes within the body that it would be very difficult for me to tell you all of the things vitamins are needed for. The fundamentals of cells depend greatly upon vitamins. Vitamins are responsible for keeping cells strong, binding tissues, fighting infections, etc. Without vitamins our cells would not function properly and thus our organs would suffer and eventually we would no longer be able to survive. Vitamins help regulate metabolism, help convert fat and carbohydrates into energy, and assist in forming bone and tissue.
Vitamin A works in our immunological systems strengthening membranes thus fighting infections, it works in our eyes aiding vision, it helps our ears by treating otosclerosis, it helps jawbone and tooth formation, healthy mouth membranes and gums, keeps our skin clear and keeps our reproductive systems healthy including fertility and sperm production.
The vitamin B complex is probably one of the most essential groups of vitamins to our health. There are twelve B vitamins: B1, B2, B3, B5, B6, B12, biotin, pantothenic acid, choline, folic acid, inositol, and PABA. These vitamins together are responsible for helping enzymes release energy from food, promote proper metabolism, give cells plenty of oxygen, detoxify organs, stabilize your nervous system functions, help skin and hair be healthy, prevent defective vision, and have been used in treatment for debilitating conditions.
Vitamin C is by far the most essential vitamin in my opinion. This vitamin does things that you would never believe. I can't tell you all it does so you will have to go and look it up but here are a few of the things. Its most important functions are helping wounds heal, fight infections, strengthen blood vessels, and it is a major antioxidant.
Vitamin D is often called the "Sunshine" vitamin because that is where we get it from. Vitamin D helps your body utilize calcium and phosphorus, which helps form strong bones, teeth and healthy skin.
Vitamin E guarantees that the organs have all the oxygen they need, it strengthens capillary walls and rejuvenates blood, and it helps skin lesions heal internally and externally.
To learn more about these vitamins connect to this link: http://www.realtime.net/anr/vitamins.html
Now that we know a little about what vitamins are and what they do for our bodies we need to know where to get them. The obvious place is in food. Another place we can get vitamins is from dietary supplements but the experts say that eating foods that are rich in nutrients is the best way to get all the needed vitamins and minerals. (We will talk about dietary supplements later anyway). Part of your nutrient rich diet should include lots of whole grains, fruits and vegetables. In addition to healthy eating maintaining a healthy weight can be reached by eating balanced, sensible meals and exercising regularly. But, do not eat huge portions or you won't get all the nutrients you need and will end up overloading on one and not the others. Be careful not to skip meals and do not cut out unhealthy foods just reduce their consumption. One tip for healthy eating is to pay attention to the Food Guide Pyramid, http://www.realtime.net/anr/10eattip.html . This site will tell you how many servings and what constitutes a serving, for example, did you know that a glass of juice is considered a serving of fruit? Or that one egg counts as a serving of meat? I bet it doesn't seem so hard to meet those requirements any more.....
Anyway, now you might be asking what foods contain what vitamins and if you just hold on a minute I will tell you.
Vitamin A is found in animal foods like liver, butter, whole milk, cheese, and egg yolks. In plants, vitamin A occurs in carotene such as yellow vegetables, spinach, beet greens, carrots, and turnips.
Vitamin B1, Thiamine, can be found in whole grains, poultry, liver, fish, seeds, nuts, brewers yeast, bran and wheat germ.
Vitamin B2, ribolflavin, is found in dairy products, meat, poultry, fish, whole grains, and leafy, green vegetables.
Vitamin B3, Niacin, can be found in salmon, tuna, wheat germ, brewer's yeast, green, leafy vegetables, beans, peas, dried figs, prunes, and dates.
Vitamin B5, Pantothenic Acid, is found in many common foods such as meat, egg yolks, peanuts, whole grains and beans.
Vitamin B6, Pyridoxine, is in salmon and herring, pork liver, bananas, pears and brown rice. Eat lots of whole grain cereal, beans, meat, and fresh vegetables and you should have plenty.
Vitamin B12 is manufactured by microorganisms so it is not found in fruits and vegetables. Meat, poultry, non-fat dry milk, and fermented soybean products like tempeh will give you what you need. Vegetarians need to be aware of sufficient vitamin B12.
Folic Acid has been the talk of late and there is a great need for women who are of child bearing age to be aware they are getting enough. Folic Acid can be found in foods like kale, green, leafy vegetables, kidney, liver, spinach, parsley, brewer's yeast, and watercress. This vitamin helps prevent neural tube defects and miscarriages.
PABA, Para-aminobenzoic Acid, can be found in eggs, brewer's yeast, molasses, wheat germ and whole grains. Yes, like PABA in sunscreen.
Choline is prominent in eggs, liver, beans, bran, whole grain, nuts, lecithin, meat, and fish. Choline is essential to regulating cholesterol levels so mind your choline levels.
Inositol is found in most of the B carrying foods but also found in oranges, nuts and molasses.
Biotin, the last of the B vitamins, is manufactured in the intestinal tract due to microorganisms stimulated by inositol. It is also found in eggs, cheese, nuts and other common foods.
Vitamin C, the most accessible vitamin, is found in large quantities in broccoli. Next is sweet green peppers. Then you can find it in almost all fruits and vegetables. Citrus, potatoes, collards, anything with color it seems.
Vitamin D, if you like the sun you probably have plenty of vitamin D. If you are not a sun-lover here is where you can find it too: fish liver oils, fortified foods like butter and milk, seafood, and egg yolks.
Vitamin E is ideally found in wheat germ and wheat germ oil. The other
ways of getting it sound a little more appetizing, whole grain baked goods,
seeds, nuts, bran, and unrefined cereal.
***A smart thing to do when buying foods is to check if they have these
vitamins and the quantity contained. We will talk about RDA soon but you
can go now if you would like. How Much
Do We Need***
Obviously that is a silly question. I bet if you think hard enough you can get the answer. O.K., the answer is EVERYONE! Without vitamins our bodies cannot perform their normal daily functions. We wouldn't be able to think, fight infection, run, laugh, work, and sleep. The list goes on and on but here are some interesting facts to keep you on your toes.
If you are really tired you might be deficient in Thiamin, B12, Biotin and PABA. If you are prematurely gray you could be deficient in Folic Acid or PABA. Night Blindness is related to deficiencies of Vitamin A. Feeling sad? B1, PABA and B12 deficiencies can be related to mental depression. Loss of sleep or insomnia? Check your intake of B3 and B6. Body aches, weakness, soft or bleeding gums, anemia and loss of appetite can be traced back to deficiencies in Vitamin C, Folic Acid, Vitamin A, Vitamin B1, B6, and Vitamin D. One more interesting fact, do you lack sexual vitality? If you do try some more Vitamin E.
The people that mainly need to look out for their vitamin intake are the special cases. Vegetarians need to be aware of alternative ways to get nutrients usually found in meats. More importantly the Vegans need to too. Pregnant women definitely need to watch what they eat and make sure it is nutritionally enough for the baby, especially Folic Acid. Next, the elderly need to watch out. Studies have shown that proper nutrition can result in a graceful and healthy aging process. (http://www.realtime.net/anr/pmkidd.html ). All in all most Americans could benefit from a revamping of their nutritional lifestyle. Many Americans are too concerned with time constraints and the hustle and bustle of daily life. Take time to stop and eat some fruit, make a salad, or cook yourself a healthy dinner. Chances are you will feel better, your body will work more efficiently and you probably won't get sick very often.
So, now you are thinking, I know where to find my vitamins, I know why
I need them, and I know what they do for me but.....how much do I need?
Remember the Food Guide Pyramid? That tells us the servings we need from all the basic food groups. What is in those servings is what really counts. It is now a law that manufacturers must put all the nutrition facts on the labels of products. This is a fairly simple and easy way to find out what nutrients are in what foods. As far as fruits and vegetables go some grocery stores will have the nutrition information posted and if it is not there are plenty of books out there to give you the run down.
Sometimes these labels can be confusing though. It lists all the nutrients
and the percentage of the Recommended Daily Allowance (RDA) of each nutrient,
but what does the RDA mean? The RDA is a "guesstimate" of the
amount of a particular nutrient the body needs per day in order to function
at a safe level. There is some controversy about how accurate the RDA for
nutrients is. One Harvard Professor claims that the RDA is a "guesstimate
of unknown reliability" and the RDA board admits " that its values
are not meant to create 'optimal health' in that the RDA's are only the
suggested 'minimum' or 'adequate' daily requirements" (http://www.realtime.net/anr/vitaneed.html).
It seems that in actuality we need to consume more vitamins and minerals
than we thought. In practicality we probably do, especially as Americans.
Americans tend to eat larger portions of most foods and eat more during
the day. Also, if you think about it 3/4 cup of juice is one serving but
that is only four ounces and most glasses are eight ounces, so there is
two servings of fruits in one sitting. So, do not feel too bad about not
getting the right amounts of nutrients but try and beware of what kinds
of foods you eat.
***Most foods that are processed lose nutritional value and activities such as smoking and drinking aid in the expulsion of important nutrients before they are absorbed (http://www.realtime.net/anr/vitaneed.html).***
Some important facts need to be addressed about the recommended dosage of some vitamins. This might help put things into a better perspective if you are confused. There is a list of the Recommended Daily Allowances for adults including all of the vitamins and minerals and the quantity that is suggested.(http://www.hawkesbury.uws.edu.au/~geoffs/rdi.txt). This list should tell you what your particular gender and age requires.
Another thing that is important about vitamins is their effects on each other. Large doses of Beta Carotene will increase the body's demand for vitamin E so you should increase E doses. Vitamin E is an important antioxidant and eats up the free radicals that cause degenerative diseases, so we need to be aware that vitamins E and C are antioxidants and that they are most important in fighting cancer. E is also responsible for stabilizing the vascular system, decreasing leg cramps and as a topical soother for skin irritations. B complexes might be the most important vitamins to take. They are membrane stabilizers. They help relieve stress and stabilize the body. For women taking oral contraceptives more B vitamins are needed because they are used up faster. B vitamins must be taken with food to avoid nausea. Fair complexion people benefit greatly form B vitamins due to PABA. Vitamin C is also essential to one's health. Its main function is to heal tissue. Studies show that C can reduce chances of colon cancer. Vitamin C aids in the absorption of iron and decreases bruising. These and more facts are available at (http://www.realtime.net/anr/anrrda.html).
~Intersting little tid-bit: Pregnant women need different amounts of
vitamins and if you are interested in what they need click on this link
So, at this point you might be wondering what happens if you can't get all the vitamins that you need what should you do? The most logical thing to do would be to go out and buy a bottle of Centrum and take one every day, right? That is what I did. But before you go out and buy that bottle of Centrum let's get the facts straight.
A supplement is a pill form of one vitamin or a bunch of vitamins. Supplements must be taken with food in order for them to be effective. The pills use the food as their way of being absorbed and distributed throughout the body. "Surveys show that only 9% of North Americans eat the recommended five daily servings of fruits or vegetables that would provide the minimum level of nutrients believed necessary to prevent llness" (http://www.lynnford.com:80/whyvit.htm). The other 91% of Americans probably should take dietary supplements.
One study showed that "burn trauma victims fared far better when given extra nutritional supplementation over and above the normal 'well balanced diet' generally prescribed by practitioners. 100% of those children receiving the extra supplementation lived, whereas 44% died who were given the regular doses" (http://www.realtime.net/anr/vitaneed.html). Vitamins help the body heal faster.
Another study was conducted in which women who ate normally produced "normal" children and those who ate a diet of nutritionally enriched foods had children who were "above normal". The "above normal" children displayed superiority on physical, emotional, and intellectual tests. So, supplementing diets in pregnant women enhances the life of the child. (http://www.realtime.net/anr/vitaneed.html).
A recent poll of "Newsweek" said "seven out of ten American use supplements at least occasionally"(Anonymous). "The Department of Health's line on supplementation is that we should be able to get all vitamins and nutrients from a well balanced diet"(Seymour, J.). The American Dietetic Association emphasizes the importance of micro and macro nutrients found in the body as essential along with the consumption of a wide variety of foods. "It is the position of the American Dietetic Association that the best nutritional strategy for promoting optimal health and reducing the risk of chronic diseases to obtain adequate nutrients from a wide variety of foods. Vitamin and mineral supplementation is appropriate when well-accepted, peer-reviewed, scientific evidence shows safety and effectiveness"(Anonymous). There are various amounts of information claiming that food fortification is better than supplementation. Another study says that people that already take supplements tend to eat more fruits and vegetables anyway.
Supplements are most accepted and needed when there are special cases that demand their use. The Department of Health recommends that pregnant women take supplements of folic acid to prevent NTD. Vegans need extra B12 and people around limited light or milk intake need vitamin D. Lactose intolerants need extra calcium along with post-menopausal women. Finally, those who are following severely restricted weight loss diets need to take multi-vitamin and mineral supplements.
The evidence seems mixed. The authorities seem to think that we shouldn't take supplements and that we should get our nutrients from food. The studies show that supplements have aided in better health, superior healing and better test performances. The one area of agreement is that people with special needs should take dietary supplements. So, supplements don't seem to harm us and if we don't think we are getting enough from our diets we should take them but try and get as much as you can from the foods you eat.
If you are still a little confused or unsure there are some more formal
studies done on the effects of dietary supplements and vitamins on athletes,
pregnant women and evryday people.
For a long time people have often wondered the significance of vitamins in our lives. It is difficult to study all the vitamins and all of their effects so we are given a limited amount of topics. Most have to deal with vitamins that are directly related to a certain disease or illness. There are three main bodies of research done on the subjects of vitamins and dietary supplements. The first is studies done on the general public. The second is studies done on pregnant women and babies. The third area is done on athletes.
One study focused on the nutrient intake of vegetarian versus non-vegetarian women(Janelle, K.C. and Barr, S.I., 1995). The study compared vegetarians with nonvegetarians who had similar health practices. The results concluded that both groups adhered closely to the daily recommendations. Vegetarians had lower riboflavin, niacin, B12, zinc and sodium intakes and higher folate, vitamin C, and copper intakes. The conclusion was that nutrient intake among vegetarians and nonvegetarians can be equally close to the recommendations and that vegetarians may need to watch their diets a little more closely.
Another study assessed the need for more folic acid. (Oakley, Adams, and Dickinson, 1996). The research shows that people who do not take folic acid supplements are at an increased risk for functional folate deficiency, which has been proven to cause spina bifida and anencephaly and has also been associated with an increased risk for occlusive cardiovascular disease.
Along those same lines one study was done on the effects of supplementation of folic acid in pregnant women. (Mills and Conley, 1995). The research shows that women must receive folic acid before or immediately after conception in order to prevent neural tube defects. It is almost impossible to fortify foods with folic acid for fear that it will expose other members of the population to dangerous levels. Thus, there is medical controversy.
Other studies reinforce this finding about the need for folic acid supplementation and for other vitamin supplements in pregnant women. Periconceptual care including vitamin supplementation can greatly reduce the chances of NTD's and birth defects. (Czeizel, 1995).
Further research uses athletes and their performance as indicators of successful vitamin supplementation. One study on female collegiate rowers (Steen, Mayer, Brownell and Wadden, 1995) concluded that these athletes needed more vitamins and minerals and less fats and carbohydrates. They could benefit from supplements.
Another study by Maresh et al., 1994, concluded that dietary supplementation improved anaerobic exercise. This seems to say that it would be beneficial for athletes to take supplements when needed.
The research seems to support the claims made by the Department of Health
and the American Dietetic Association, that supplements are not bad and
can help in many cases but are needed only in extreme cases. Vitamins can
have very important effects if not taken or taken incorrectly. Vitamins
can most of all help us feel good, keep us healthy and happy, heal us when
we hurt, and make sure everything is running smoothly.
A Lot! We have learned what vitamins are, why we need them to live,
where we can find them, who needs to have them, how much we need and some
interesting facts too. As I have said before vitamins are the basis of
living. We all know that cells are the basic building blocks of our bodies.
Without healthy cells the rest of our bodies cannot work. Vitamins keep
our cells healthy. Thus vitamins are one of the basic needs of human life.
It means that you need to be conscious of your nutritional intake. It
means that to maintain a normal weight you need to eat balanced nutritional
meals and exercise regularly. It means that if you are pregnant you need
to make extra special efforts to receive nutrients. It means that supplements
are O.K. but not ideal. It means that if you consume the vitamins you need
you have a better chance of not getting cancer, other infections, and a
series of other common problems associated with vitamin deficiencies. Most
of all it means that your mother was right when she told you to "take
~ For more information check out these websites: http://www.ozemail.com.au/~bookman/vitdef.html
Anonymous. "Position of the American Dietetic Association: vitamin and mineral supplementation". Journal of the American Dietetic Association. 96(1):73-7, 1996 Jan.
Beltz, SD and Doering, PL. "Efficacy of nutritional supplements used by athletes". Clinical Pharmacy. 12(12):900-8, 1993 Dec.
Czeizel, AE. "Primary prevention of birth defects by periconceptual care, including multivitamin supplementation". Bailleres Clinical Obstetrics and Gynaecology. 9(3):417-30, 1995 Sep.
Janelle, KC and Barr, SI. "Nutrient intakes and eating behavior scores of vegetarian and nonvegetarian women". Journal of the American Dietetic Association. 95(2):180- 6, 1995 Feb.
Maresh, CM; Armstrong, LE; Hoffman, JR; Hannon, DR; Gabaree, CL; Bergeron, MF; Whittlesey, MJ; Deschenes, MR. "Dietary supplements and improved anaerobic exercise". International Journal of Sports Nutrition. 4(4):387-97, 1994 Dec.
Mills, JL and Conley, MR. "Periconceptual vitamin supplementation to prevent neural tube defects: how can we do it?". European Journal of Obstetrics, Gynecology, and Reproductive Biology. 61(1):49-55, 1995 Jul.
Null, Gary. The Complete Guide to Health and Nutrition. Dell Publishing. New York, New York. 1984.
Oakley, GP Jr.; Adams, MJ; Dickinson, CM. "More folic acid for everyone, now". Journal of Nutrition. 126(3);751s-755s, 1996 Mar.
Seymour, J. "Nutrition: vitamins and supplements". Nursing Times. 91(17):48-50, 1995 Apr 26- May 2.
Steen, SN; Mayer, K; Brownell, KD; Wadden, TA. "Dietary intake of female collegiate heavyweight rowers". International Journal of Sports Nutrition. 5(3):225-31, 1995 Sep.
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