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Vitamin C (Ascorbic Acid)


  1. I have to write about vitamin C in oranges vs. vitamin C in supplements. Which would you say is better? Answer
  2. I was pregnant when the issue first came up. I was not about to take any changes with a high vitamin C dependence. Answer
  3. Yes I meant 50 grams a day seemed to much to me especially since I was pregnant at the time. Answer
  4. My father a doctor wants me to take this high dose vitamin C supplement. Isn't it dangerous to take such a high dose? Answer
  5. I am taking a supplement of 1 gram of vitamin C as an antioxidant. What are the collateral effects related with the excess? Answer
  6. I haev a question regarding bruising. I am wonderinf if I am lacking a certain vitamin or mineral that I should take? Answer
  7. Does cooking destroy vitamin C? Answer


Hi! I was wondering if you could help me with an extended essay that I have to write regarding vitamin C in oranges vs. vitamin C in supplements. Which would you say is the better? Do you know of any experiments that I could perform in order to prove which is the better? Thanks a million!

Food is always better.

As to experiments to perform, you would need an animal that does not produce vitamin C which is only humans and very few large mammals. Would not recommend making a human vitamin C deficient as our immune system depends on vitamin C. Don't have any suggestions on how to prove that food vitamin C is better than supplement vitamin C since both will deliver vitamin C in an active form. Problem is the human organism lives so long that nutrient impacts like sources of nutrients (food vs supplements) would be difficult to prove in a short time.

Would recommend you do a PubMed (medical literature) search for "vitamin C sources" and look for studies that considered vitamin C sources. Perhaps you would get some experiment ideas there.


I was pregnant when the issue first came up---about a year ago and believe me, I was not about to take any chances. The high vitamin C dependency makes sense. I know my dad. Any opinion that is not his will be questioned immediately! Thanks again.

Here's a Vitamin A supplement fact. During pregnancy, the risk of birth defects rises steadily if the daily intake exceeds 10,000 I.U.


Thanks for the advice. Yes, I meant 50 grams a day and it seemed too much too me, especially since I was pregnant at the time and was not about to take anything experimental. My dad got his medical feelings hurt over the whole issue and is still mad at me. But this is the man who takes medication so he doesn't have to go to the bathroom during a 12 hour trip. I read your recommendation that a balanced diet might make supplements unnecessary. Thank you so much.

Whoa, you're pregnant ?

Definitely don't take any supplements other than those prescribed by your obstetrician (folic acid to prevent neural tube defects like spina bifida, iron to prevent anemia and Vitamin C at 1 - 2 times RDA amount only or 150 milligrams to improve iron absorption). Other nutrients needed for pregnancy can be acquired by eating a balanced eating plan with sufficient calories to support a healthy weight gain. Try my Healthy Body Calculator and include that you are pregnant so your report will include the increased calories and nutrients you need during your pregnancy. Better to have a mad dad than a baby with life long problems due to megadoses of vitamin supplements. Besides, time has a way of healing most rifts, especially when you deliver a healthy, well nourished baby.

FYI, some Vitamin C research concluded that mothers who took megadoses (100 times the RDA) of vitamin C produced babies who were more vitamin C dependent throughout their lives. It seems these babies had to continue supplementing above the RDA to reach normal body saturation levels due to the extremely high levels during their intrauterine life.



My father, a general practitioner doctor who (in my opinion) tends to overmedicate, wants me to take this high dose vitamin C supplement. If I remember correctly, he recommends 50 milligrams a day. Isn't it dangerous to take such a high dose. Thanks.

The RDA (Recommended Dietary Allowance) for Vitamin C is 90 milligrams per day for adult males and 75 milligrams per day for adult females, 19 to 70+ years of age. Therefore 50 milligrams would be less than the RDA. Did you mean 50 grams? If so, yes, that is a megadose and I would not recommend supplementing with 50 grams of Vitamin C per day.


I am taking a supplement of 1 gram of vitamin C as an antioxidant. What are the collateral effects related with the excess of Vitamin C?

First of all it turns your urine yellow. It makes your urine more acid, which decreases urinary pH and possibility of urinary tract infections.

Beyond that 1 gm of Vitamin C per day is excessive as an antioxidant; 500 mg would be sufficient, according to the latest research on cancer and antioxidants.


I have a question regarding bruising. I am a very active person, but I bruise a lot easier than I've noticed on other people. Also, when I do bruise, bruises stay for quite a while. I have started taking my multivitamin at the recommended dosage, but I am wondering if I am lacking a certain vitamin or mineral that I should take additionally. I always try to have a very healthy diet. Is there a solution? It is almost embarassing to have bare legs and arms.

Are you on a drug called Coumadin or taking a herbal supplement like ginkgo? These are blood thinners and can increase the ease of bruising or severity of the bruise even from a slight injury. If you are on coumadin, then your doctor should be checking your clotting time (prothrombin) periodically to make sure it is not too long. If you are on ginkgo, perhaps you should review with your doctor the need for ginkgo. Persons on Coumadin should not take ginkgo as their bleeding time would be too long.

Bruises appear darker and more readily on people with fair skin. People with darker skin have more melonin pigment in their skin, so bruises don't appear as easily. Taking a multivitamin with 100% of the Recommended Dietary Allowances is fine and one pill probably contains 100% of the RDA for vitamin C. Read the bottle label to be sure.

Vitamin C makes small blood vessels less fragile and helps reduce bruising. A vitamin C supplement is not necessary in addition to your multivitamin, however, if you follow the recommendations of the Food Guide Pyramid for 5 fruits and vegetables each day, you can get more vitamin C. Eat foods that are rich sources of vitamin C like orange juice, citrus fruits, kiwi, green peppers and broccoli, which may reduce the severity of your bruising.

Vitamin K helps improve clotting time and good foods sources of vitamin K are green vegetables, soybeans, dried beans or peas. Do you get enough of these foods each day?


Does cooking destroy vitamin C?

Vitamin C is the most easily destroyed vitamin there is. It is destroyed by oxygen, heat (above 70 degrees) and it leaks out into the cooking water because it is a water soluble vitamin.

To preserve vitamin C in food, store citrus fruits, tomatoes, juices, broccoli, green peppers, cantaloupe and strawberries in the refrigerator uncut until you need them. Prepare dishes with these foods right before serving. Also, cut these foods in larger pieces to prevent the air from destroying vitamin C. Cook these foods in as little water and as short a time as possible. Steaming and stir-frying are two methods that help conserve vitamin C content.

As long as the skin is uncut, the vitamin C is protected from air. If you store a cut fruit or vegetable or an open pitcher of juice, cover it tightly with plastic and put it in the refrigerator.

Vitamin C dissolves in cooking water so serve the food with the cooking water if possible. You can save the water from vegetables like potatoes and broccoli for making soup. Or mash potatoes with some of the potato water.

Also, cast iron pans destroy vitamin C. Don't use them in cooking vitamin C rich vegetables like tomatoes for spaghetti sauce.

Add vitamin C rich foods to casseroles. As they cook, less vitamin C will be lost.

Vitamin C can be completely lost if foods are frozen for longer than two months. Keep your freezer at 0 to -10 degrees to minimize this vitamin C loss in juices and vegetables.

Orange juice is frequently bought as a frozen concentrate. Frozen, reconstituted orange juice has 78% and canned orange juice has 69% of the vitamin C found in fresh squeezed orange juice. Vitamin C is destroyed during the condensing process, but canning is even harder on vitamin C. It appears that fresh squeezed orange juice is better than either frozen concentrate or canned, but remember that the highest Recommended Dietary Allowances for vitamin C is 60 milligrams and all three forms, fresh, frozen and canned provide more than the RDA of vitamin C in 2/3 cup of orange juice.






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