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Pros & Cons of Citric Acid in Lemon Juice

  1. Apr 26, 2005 #1
    Hey Guys,
    Sorry once again i am posting a thread of a boring topic, but seriously i couldn't find any information on the search engines that why i need your help on, the advantages and disdavantages of Citric acid in lemon juice.

    I found couple of sentences, but i don't know what it means, so i will just copy and paste the info i got, and if anyone here knows anything can you just tell me.

    "In order to have very white teeth, brush them twice a week with a mix of not diluted lemon, lime (green lemon) and grapefruit juice (same quantities). This helps also to reduce tartar. On the other way, try to avoid biting and sucking lemon juice, because of the high concentration of citric acid, a prolonged contact can damage the enamel. Lemon juice is very acidic and can dissolve tooth enamel on newly erupted teeth"

    How does a higher concentration of citric acid can damage the enamel of a tooth?

    "University of Melbourne's Professor Roger Short made the discovery that lemon juice kills the AIDS virus after he put lemon juice in a test tube with HIV-positive sperm and the sperm were permanently immobilised within 30 seconds. In Australia the Federal Government had refused to fund human trials of this discovery but Roger found the Thai government interested and they will fund a trial on at least 400 Thai men and women. Roger claims the lemon juice also killed syphilis, gonorrhoea and chlamydia. This was due to the acidity of Officials at the international AIDS conference in Bangkok announced the first human trial. "

    How come the lemon juice killed the baterias? Is it because of the high acidity of citric acid in lemon juice which killed the baterias?
  2. jcsd
  3. Apr 27, 2005 #2


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    Staff: Mentor

    1. Citric acid is acidic (nothing strange) and have some complexing abilities, thus it may help remove tartar and it may damage the enamel. This is not a rocket science.

    2. I don't get it. I am ready to show experimentally that hydrochloric acid kills HIV virus in sperm too. Sulfuric acid too, even easier, as it can be prepared much more concentrated. Perhaps there is something missing in this information, as I can't see any way of using neither citric nor hydrochloric acid to fight AIDS. I also doubt anyone will decide to use concentrated sulfuric acid for this purpose :)

    More seriously - most bacterias will die if the pH is far from neutral. There are species that can survive even pH = 1 (like Helicobacter pylori), but these are just exceptions proving the rule.
    Last edited by a moderator: Aug 13, 2013
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