Is 1,000 mg of vitamin C safe? What dosage is too much?

vitamin C needs | side effects | Mega doses | 1,000 mg | food vs supplements

Is a dose of 1,000 mg of vitamin C safe? Actually yes, but you shouldn’t take it for 2 reasons…

The recommended daily intake of vitamin C is 75 – 90 mg. It’s 75 mg for women and 90 mg for men.

Moreover, smokers need more vitamin C per day. They need additionally 35 mg of vitamin C a day, due to increased oxidative stress. A study suggested that drinking orange juice can increase plasma concentrations of vitamin C in humans. Smokers can benefit the most.[1]

Additionally, pregnant women require at least 85 mg of vitamin C, while lactating women require at least 120 mg.

Effects of Mega doses of vitamin C

So, most healthy people need around 100 mg of vitamin C a day. Way less than 1,000 mg, which is found in many supplements.

The regular consumption of 1,000 mg of vitamin C is pretty safe, though.

According to a study, researchers have treated cancer patients with high dosages of vitamin C, through IVC therapy (intravenous vitamin C). Scientists gave cancer patients up to 100 g of vitamin C a day![2] That’s 100,000 mg. 100 times more vitamin C than the 1,000 mg dose, or 100,000 times the recommended daily intake of vitamin C. That’s a huge dose. So, what happened to these patients?

Regarding cancer, researchers observed:

  • survival beyond prognosis,
  • improvement in the quality of life,
  • improved tolerance of conventional therapy,
  • deterioration in clinical condition, in the absence of vitamin C dosage.

On the other hand, the side effects of mega dosages of vitamin C seem to be minimal. Patients experienced symptoms of Jarisch-Herxheimer reaction. This is a reaction of the body to endotoxins produced by the necrosis of harmful cells. Fever, chills, strong body odor, and pimples may be other side effects.

Don’t forget that these side effects happened to cancer patients, after megadoses of vitamin C. Symptoms resolved after 2 to 3 hours, after injection with vitamin C.

Most noteworthy, therapy with high dosages of vitamin C (IVC) may:

  • stabilize cancer,
  • reduce the risk of metastasis,
  • keep tumor stable,
  • disappear breast carcinoma,
  • help on tumor shrinkage,
  • have antitumor activity in some cases,
  • help patients regain strength.

Side effects of vitamin C supplementation

High amounts of vitamin C from supplements are rather unlikely to cause any significant adverse effects. People who may experience some discomfort, are those who have:[3]

  • a history of kidney stone formation,
  • iron overload,
  • taken other drugs as well.

Side effects may be diarrhea, mild nausea, and other gastrointestinal disturbances due to the osmotic effect of unabsorbed vitamin C.[4]

What dosage of vitamin C is too much?

According to the National Institutes of Health, vitamin C has low toxicity, and it’s rather unusual to cause serious adverse effects. Even at high intakes. The maximum dosage of vitamin C for adults is 2,000 mg per day.

Always consult your health care provider before taking any supplements. Especially if you’re taking other medication. Vitamin C supplements may interact with other drugs.

What are the preferred sources of vitamin C?

There is no reason to take vitamin supplements if you eat a healthy whole food plant-based diet. Vegetables and fruits are the best dietary sources of vitamin C.

Is a daily dose of 1,000 mg safe?

In general, getting up to 1,000 mg of vitamin C is pretty safe. Most people are rather unlikely to experience any side effects.

Certainly, people on medication should consult their health care provider, before taking any supplement.

It’s a good idea to boost vitamin C intake. For instance, in the winter, vitamin C seems to be beneficial against the flu and common cold. It may boost the immune system.

We should take at least 1,000 mg of vitamin C during the summer, as well. Vitamin C naturally boosts collagen production, and protects us from skin aging! Also, it helps burn body fat and lose weight!

Certainly, eating foods high in vitamin C is the best way to get the recommended daily intake. But, boosting vitamin C intake from supplements could be beneficial as well. Especially, during certain times of the year!

You’ll find a wide variety of vitamin C supplements on iHerb.