As an antioxidant, vitamin C can help you react better to stress by reducing the activity of stress hormones in your central nervous system (CNS). It also improves vascular function and increases the secretion of oxytocin—the feel-good hugging hormone. And in animal studies, vitamin C has been shown to decrease behaviors associated with apprehension in approaching a potential mate. Turns out all of these factors can influence the frequency of having sex.
Given this potential superpower, researchers who were partially funded by a pharmaceutical company performed a small randomized, double-blind clinical trial to determine if a high-dose of vitamin C might improve mood and increase the frequency of penile-vaginal intercourse.
The researchers chose this specific type of sexual behavior because of its evolutionary status. As the only potentially reproductive sexual act, and due to the biological nature of natural selection over the eons, the researchers theorized penile-vaginal intercourse would be most likely to benefit from any influence of vitamin C.
In the study, 81 healthy young adults completed a test to measure the level of their depression and recorded how often they had sex: penile-vaginal intercourse, noncoital partner sex, and masturbation.
Then, for two weeks, while continuing to record their sexual activity, 42 participants took 3000 milligrams (mg) per day of sustained-release vitamin C, and 39 took a placebo. At the end of two weeks, all of the participants completed another test to measure their level of depression. It’s important to note that the tolerable upper intake level of vitamin C is 2,000 mg/day (i.e., the maximum amount that can be taken without risk of side effects).
Those participants who took the high-dose vitamin C reported more penile-vaginal intercourse—especially if they were women, and especially if they were not living with their partners—but not more of the other kinds of sexual behaviors. The vitamin C group also experienced a decrease in their depression scores.
This prompted the scientists to conclude the enhancement of mood as a result of taking vitamin C seemed to increase the frequency of penile-vaginal sex, and not just because participants potentially had daily access to their sexual partner.
How do you get enough vitamin C?
While plants and most animals can make vitamin C from glucose, humans cannot, so we need to get it from our diet or take supplements. These studies looked at supplemental levels of vitamin C because food sources aren’t likely to be enough to see benefits. But striving to meet your recommended daily allowance (RDA) is always a good idea.
The RDA of vitamin C is 75 mg for women and 90 mg for men. Eating five servings of different fruits and vegetables a day will provide you with more than 200 mg of vitamin C.
- Stock up on foods containing vitamin C: Citrus fruits, tomatoes and tomato juice, potatoes, red and green peppers, kiwifruit, broccoli, strawberries, Brussels sprouts, and cantaloupes are major sources of vitamin C.
- Aim to eat them raw or lightly cooked: Eating as many of these foods fresh and raw will preserve the vitamin C content, which can decrease if you store them too long or cook them on the stove over high heat. Steaming or microwaving may lessen the losses by using lower heat.
Can you take too much vitamin C?
The National Academy of Medicine has established that 2000 mg of vitamin C per day is the tolerable upper intake level (TUL) of vitamin C for adults. Vitamin C is water-soluble and not stored within your body, so if you take more than your body needs, the excess will be excreted via your urine.
But consuming more than 2,000 mg of supplemental vitamin C per day may lead to side effects like diarrhea and nausea, because unabsorbed quantities can attract fluids into your intestines. It’s important not to take more than the TUL unless under the guidance of a physician.
Can you take a vitamin C supplement with other medications?
Be sure to discuss adding extra vitamins to your diet with your doctor before taking more than the recommended daily dose.
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