Please help me understand!

iVillage Member
Registered: 07-07-2003
Please help me understand!
3
Mon, 03-01-2004 - 3:42pm
I saw that Vitamin C can mess with the pill?! Is this true? Has anyone heard of this? It says that it "May raise levels of estrogen in the blood". And that "Estrogen-related side effects may appear with vitamin C>1 gram". What does this mean? I take 1000 mg. of Vitamin C a day.

Thank you, any information is much appreciated!

iVillage Member
Registered: 06-22-2003
Mon, 03-01-2004 - 6:27pm
I don't know either but I was on the pill last year for 10 months and also took 1,000 mg of vitamin C. Nothing out of the ordinary happened to me. But I want to know also because I have to go back on the pill! Please help me understand too!
iVillage Member
Registered: 09-15-2003
Mon, 03-01-2004 - 7:28pm
The info I found says vitamin C at 1000 mg dose (which equals 1 gram) does not interfere with estrogen in the pill (see article abstract below). More than 1 gram dosage could increase the estrogen in the blood, which would most likely result in estrogen side effects like nausea or headache. It should not make the pill less effective.


Contraception. 1993 Oct;48(4):377-91. Related Articles, Links


Absence of an effect of high vitamin C dosage on the systemic availability of ethinyl estradiol in women using a combination oral contraceptive.

Zamah NM, Humpel M, Kuhnz W, Louton T, Rafferty J, Back DJ.

Truman Medical Center, Kansas City, Missouri 64108.

Previous studies in small numbers of women have suggested that the administration of gram quantities of ascorbic acid interferes with the conversion of ethinyl estradiol (EE2) to its sulfates, leading to higher blood levels of EE2. The possibility of such potentiation has been investigated in 37 women using a combination monophasic oral contraceptive (30 micrograms EE2 and 150 micrograms levonorgestrel) for two consecutive cycles. Concomitant daily administration of 1 g ascorbic acid taken 1/2 hour before OC intake, was randomly assigned to the first or second cycle of OC use. On the first and 15th day of OC intake, blood samples were drawn 11 times over a 12-hour interval and Cmax and AUC(0-12 h) calculated. On pill days 10 and 21, only 6-hour post-intake samples were obtained. Samples were analyzed for levels of ascorbic acid, free and sulfated ethinyl estradiol (and a number of other parameters). Cmax and AUC values for EE2 and EE2-sulfate in cycles with and without ascorbic acid were evaluated statistically by the Grizzle model for days 1 and 15 and the ratios of day 15/day 1 for each of the substances. No effect of ascorbic acid was observed (alpha = 0.05, 1-beta = 0.9). Only on day 15 was there a significantly lower AUC for EE2-sulfate in the presence of ascorbic acid intake. Thus, the competition between ascorbic acid and EE2 for sulfation does not lead to an increased systemic availability of EE2 and is, therefore, unlikely to be of any clinical importance. Ascorbic acid can, therefore, be removed from the list of drugs interfering with the pharmacokinetics of ethinyl estradiol.

Publication Types:

Clinical Trial

Randomized Controlled Trial

PMID: 8222665

iVillage Member
Registered: 01-04-2004
Tue, 03-02-2004 - 8:03am
I had an increase of btb while taking 1000 mg of Vit C. Once I stopped the btb stopped.