Vitamin C is a vital nutrient that’s plentiful in lots of fruit and veggies.
Getting sufficient of this vitamin is particularly necessary for sustaining a wholesome immune system. It additionally performs an necessary function in wound therapeutic, holding your bones sturdy, and enhancing mind perform (1).
Apparently, some declare that vitamin C dietary supplements present advantages past these that may be obtained from the vitamin C present in meals.
Some of the widespread causes folks take vitamin C dietary supplements is the concept they assist forestall the widespread chilly (2).
Nevertheless, many dietary supplements comprise extraordinarily excessive quantities of the vitamin, which may trigger undesirable uncomfortable side effects in some circumstances.
This text explores the general security of vitamin C, whether or not it’s attainable to eat an excessive amount of, and the potential hostile results of taking giant doses.
Vitamin C is water-soluble and never saved in your physique
Vitamin C is a water-soluble vitamin, which implies it dissolves in water.
In distinction to fat-soluble nutritional vitamins, water-soluble nutritional vitamins don’t get saved throughout the physique.
As an alternative, the vitamin C that you just eat will get transported to your tissues through physique fluids, and any additional will get excreted in urine (1).
Since your physique doesn’t retailer vitamin C or produce it by itself, it’s necessary to eat meals which might be wealthy in vitamin C every day (1).
Nevertheless, supplementing with excessive quantities of vitamin C can result in hostile results, reminiscent of digestive misery and kidney stones.
That’s as a result of in case you overload your physique with larger-than-normal doses of this vitamin, it’s going to begin to accumulate, probably resulting in overdose signs (3).
It’s necessary to notice that it’s pointless for most individuals to take vitamin C dietary supplements, as you’ll be able to simply get sufficient by consuming recent meals, particularly fruit and veggies (1).
An excessive amount of vitamin C might trigger digestive signs
The commonest aspect impact of excessive vitamin C consumption is digestive misery.
Normally, these uncomfortable side effects don’t happen from consuming meals that comprise vitamin C, however moderately from taking the vitamin in complement kind.
You’re almost certainly to expertise digestive signs in case you eat greater than 2,000 mg without delay. Thus, a tolerable higher restrict (TUL) of two,000 mg per day has been established (1, 3, 4, 5).
The commonest digestive signs of extreme vitamin C consumption are diarrhea and nausea.
Extreme consumption has additionally been reported to result in acid reflux disorder, though this isn’t supported by proof (1, 3, 4, 5).
For those who’re experiencing digestive issues because of taking an excessive amount of vitamin C, merely in the reduction of your complement dose or keep away from vitamin C dietary supplements altogether (3, 4, 5).
Vitamin C might trigger iron overload
Vitamin C is thought to reinforce iron absorption.
It may possibly bind to non-heme iron, which is present in plant meals. Non-heme iron is just not absorbed by your physique as effectively as heme iron, the kind of iron present in animal merchandise (6).
Vitamin C binds with non-heme iron, making it a lot simpler on your physique to soak up. This is a crucial perform, particularly for people who get most of their iron from plant-based meals (7).
One research in adults discovered that iron absorption elevated by 67% once they took 100 mg of vitamin C with a meal (8).
Nevertheless, people with circumstances that improve the chance of iron accumulation within the physique, reminiscent of hemochromatosis, ought to be cautious with vitamin C dietary supplements.
Underneath these circumstances, taking vitamin C in extra might result in iron overload, which may trigger severe harm to your coronary heart, liver, pancreas, thyroid, and central nervous system (9, 10, 11).
That stated, iron overload is very unlikely in case you don’t have a situation that will increase iron absorption. Moreover, iron overload is extra more likely to happen when extra iron is consumed in complement kind.
Taking dietary supplements in excessive doses might result in kidney stones
Extra vitamin C is excreted from the physique as oxalate, a bodily waste product.
Oxalate usually exits the physique through urine. Nevertheless, underneath some circumstances, oxalate might bind to minerals and kind crystals that may result in the formation of kidney stones (12).
Consuming an excessive amount of vitamin C has the potential to extend the quantity of oxalate in your urine, thus rising the chance of growing kidney stones (13).
In a single research that had adults take a 1,000-mg vitamin C complement twice every day for six days, the quantity of oxalate they excreted elevated by 20% (13).
Excessive vitamin C consumption is just not solely related to larger quantities of urinary oxalate but additionally linked to the event of kidney stones, particularly in case you eat quantities larger than 2,000 mg (6, 14).
Reviews of kidney failure have additionally been reported in individuals who have taken greater than 2,000 mg in a day. Nevertheless, that is extraordinarily uncommon, particularly in wholesome folks (15).
How a lot vitamin C is an excessive amount of? – “vitamin c 2000 mg”
Since vitamin C is water-soluble and your physique excretes extra quantities of it inside a couple of hours after you eat it, it’s fairly tough to eat an excessive amount of.
Actually, it’s almost inconceivable so that you can get an excessive amount of vitamin C out of your weight-reduction plan alone. In wholesome folks, any additional vitamin C consumed above the really useful every day quantity merely will get flushed out of the physique (16).
To place it in perspective, you would want to eat 29 oranges or 13 bell peppers earlier than your consumption reached the tolerable higher restrict (17, 18).
Nevertheless, the dangers of vitamin C overdose are larger when folks take dietary supplements, and it’s attainable to eat an excessive amount of of the vitamin in some circumstances.
For instance, these with circumstances that improve the chance of iron overload or are liable to kidney stones ought to be cautious with their vitamin C consumption (6, 10, 19).
All of the hostile results of vitamin C, together with digestive misery and kidney stones, seem to happen when folks take it in mega doses larger than 2,000 mg (20).
For those who select to take a vitamin C complement, it’s best to decide on one which incorporates not more than 100% of your every day wants. That’s 90 mg per day for males and 75 mg per day for ladies (21).
The underside line
Vitamin C is usually protected for most individuals.
That is very true in case you get it from meals, moderately than dietary supplements.
People who take vitamin C in complement kind are at larger threat of consuming an excessive amount of of it and experiencing uncomfortable side effects, the most typical of that are digestive signs.
Nevertheless, extra severe penalties, reminiscent of iron overload and kidney stones, may consequence from taking excessive quantities of vitamin C (3).
Fortuitously, it’s straightforward to forestall these potential uncomfortable side effects — merely keep away from vitamin C dietary supplements.
Until you’ve got a vitamin C deficiency, which hardly ever happens in wholesome folks, it’s most likely pointless so that you can take giant doses of this vitamin.