Any side effects to having too much Vitamin C?

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Cakewalk25
Cakewalk25 Posts: 71 Member
in Food and Nutrition
Almost every day I am at 700 or 800% of how much Vitamin C I should have. I'm getting it from a green smoothie I drink every day (spinach/spring mix + 1 cup frozen fruit), an apple or pear for a snack in the afternoon, and then some berries for a yogurt parfait I make before bed.

I can't seem to stay within the range for it without completely eliminating fruit from my diet, which is difficult to do as I do get hungry without any snacks between meals and fruit is an easy low-calorie snack. Is it bad to have so much extra Vitamin C than the recommended amount?

Thanks in advance for any advice anyone can give!

Replies

  • editorgrrl
    editorgrrl Posts: 7,060 Member
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    Vitamin C is water soluble. You just pee away any excess.

    High sodium is a worry. High C is fine.
  • slembke
    slembke Posts: 2 Member
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    Vitamin C is a water soluble vitamin. So most of your excess should leave your body in your urine. However, there is a slight risk of kidney stones, diarrhea, and gout.
    Here is a link for more information:
    http://www.ext.colostate.edu/pubs/foodnut/09312.html
  • FP4HSharon
    FP4HSharon Posts: 664 Member
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    Agree w/the last poster. I supplement about 1000 of C/day usually. But when I start getting sick, I take 500 mg every 3 hrs, but ONLY for the first 3 days. After that, I go back to the normal range. I'd also read that too much can lead to kidney stones & gout in particular.
  • michael300891
    michael300891 Posts: 275
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    First up, Vitamin C is a water-soluble vitamin. What that means is that in theory, any excess will simply pass out through urine. This is important because other vitamins (A D E and K) are fat-soluble and can build up in fat tissue reaching toxic levels.

    As for the side effects.

    Vitamin C's current upper intake limit is 2000g/day in adults.

    If you at 800% of the RDA that means your taking about 90g*8 = 810g.

    The upper intake limits are based on what is considered "toxic" or damaging. You are no-where near that at this point so I wouldnt worry to much.

    Only concern is that exogenous (i.e. consumed in food) antioxidants (vitamin C acts as an antioxidant) may reduce training adaptation particularly for muscle growth.

    Let me know if you want more information on that last point.

    Cheers, mike.
  • Cakewalk25
    Cakewalk25 Posts: 71 Member
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    Thanks so much for the replies! That's very helpful. Guess I can continue on the same food plan then!
  • HappyStack
    HappyStack Posts: 802 Member
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    People say urine, it isn't excreted solely through urine.

    If you get the trots, it could be symptomatic of ingesting too much vit C... we all have varying upper tolerable limits. You're looking at a couple or few grams (2000mg = 2g) though.

    Also, if you're sick, you want more vit D than C.
    If you at 800% of the RDA that means your taking about 90g*8 = 810g.

    RDI is 40mg in the UK, 45mg from the WHO and 75-90mg (female/male) in the US. 2g (2000mg) is the supposed upper tolerable limit for adults.
  • michael300891
    michael300891 Posts: 275
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    My apologies was using US values. In all honesty I do not have the vitamin C RDA commited to memory so I googled it haha!

    Just in case anyone else is interested just had this discussion with the OP

    From OP

    "The response may be of some use to others:

    "Only concern is that exogenous (i.e. consumed in food) antioxidants (vitamin C acts as an antioxidant) may reduce training adaptation particularly for muscle growth. "

    Do you mind telling me more about this?? I am addicted to taking Emergen-C lol - I may be negating my workout efforts!

    thanks! "


    My response:


    "OK so just for a bit of background, in the 1980's a theory came along based on some early animal studies that during exercise free radicals are produced and that these damage cell tissue. This led to a hell of a lot of scientific research documenting the short-term damaging effect of these radicals (hydrogen peroxide, hydroxide radical etc).

    In response, came the wave of evidence for antioxidants such as vitamin C, E etc. These clearly prevented the damage.

    What has only been really investigated over the last ten-fifteen years is what happens on a longer term basis.

    The radicals produced actually trigger through various mechanisms the nfKB pathway which upregulates various genes associated with exercise adaptation. In other words, excessive consumption of antioxidants such as Vitamin C, can blunt training adaptation.

    http://ajcn.nutrition.org/content/87/1/142.short Heres a great study looking at the blunting effect in endurance training - Gomez-Cabrera is a name well associated with this type of research if you wanted to read more.

    Proving this theory in resistance training is a lot more difficult because far less radicals are produced and gains are more related to load but this review paper discusses it to some extent. - http://www.sciencedirect.com/science/article/pii/S0300483X03001513

    Just for follow-up in general consuming excessive antioxidants which is heavily promoted is not actually good for health....

    http://www.pnas.org/content/106/21/8665.short - " Consistent with the concept of mitohormesis, exercise-induced oxidative stress ameliorates insulin resistance and causes an adaptive response promoting endogenous antioxidant defense capacity. Supplementation with antioxidants may preclude these health-promoting effects of exercise in humans. ". "


    Note: PLEASE DO NOT AVOID VITAMINS FROM DIETARY INTAKE - Just don't want you to think you need ridiculous amounts of supplements to be "healthy"

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