What men generally hope for when it comes to sexual health is an enthusiastic libido and a similarly enthusiastic erection (and possibly super-sperm, depending on your procreative goals).
But not all of that is out of your control. One thing you can choose to triumph over is a poor diet. Yes -- not only does healthy food affect how you look in your underwear, it also holds sway over what's underneath them.
And lest you reach for the gummy vitamins, experts agree that it's better to get most of your vitamins from food, not from supplements. On this one, there's no quick fix.
So read on -- we've got five nutrients you need to know.
Lemons: They're not just for fighting off scurvy! The vitamin C you find in all that is citrus-y, along with peppers, potatoes and strawberries, increases blood flow.
That's important because pressurized blood is what gives you an erection -- the arteries that go to that oh-so-crucial area open up, while the veins going out of it narrow. (You can learn more about the process in How Viagra Works.) Your blood is now where it needs to be, and since it has nowhere to go, your penis has to accommodate it somehow. Vitamin C helps this process happen.
An added benefit for older men, who are more prone to them to than younger guys: Vitamin C can help you get rid of a urinary tract infection (UTI) [source: NKUDIC].
Be careful not to take too much, though (never more than 2,000 milligrams -- stick with 90) -- we can all agree that nothing ruins the mood quite like diarrhea.
Folic Acid/Folate (Vitamin B9)
No, it's not that scientists can't decide on a name. Folate is what we call the natural vitamin that's found in foods, while folic acid is the man-made version that you find in supplements.
It's also added to your pasta, cereal, flour and all of your other enriched grain products, if you live in the United States. The U.S. Food and Drug Administration (FDA) mandated its addition in 1996 once researchers discovered that it reduces the risk of serious birth defects, such as spina bifida, in babies. (If you're trying to conceive, make sure she's getting the folic acid she needs.)
But besides this incredibly important advance in medical knowledge, some studies have shown a connection between folate/folic acid and a reduction in abnormal sperm. Others even suggest it can help increase sperm count if you combine it with zinc.
Bag up some peas (black-eyed or otherwise), asparagus and avocado -- or, if you're more of the sweet-tooth-type, try bananas, papaya and cantaloupe. Tomato juice works, too, but we're not counting Bloody Marys.
Carnitine and Vitamin E
OK, so we're cheating a little bit on this one -- carnitine isn't a vitamin. But while vitamin E has shown in some studies to improve sperm activity, there's much better evidence for carnitine, something your body uses to transform fat into energy [source: NYU Langone Medical Center].
It's not considered an essential nutrient, and you get what you need from your own body -- your liver and kidneys make it for you (although you can use it as an excuse to eat more steak, ice cream and cheddar cheese if you want -- they're all good sources).
Even though you don't need any more than your body produces, supplements of carnitine have shown to help with sexual dysfunction, the effectiveness of Viagra, and sperm quality and motility. It's not definitive evidence -- a couple of studies contradict each other. But science has its eye on carnitine, so stay tuned.
As for vitamin E, it has enough other benefits for you to love -- it's an antioxidant, it strengthens your immune system, and keeps your blood from clotting dangerously, among other functions your cells need. And you can find it in foods that are good for snacking, like almonds, peanuts and sunflower seeds.
No one wants a vitamin deficiency, especially when that vitamin is one that takes care of your nerves and blood cells. And that goes double if this same nutrient is one of several that keep you from experiencing anemia, a condition that makes you incredibly tired and weak and gives you a lovely ghostly pallor.
The vitamin is B12, and you can only get it from animal foods -- lamb, liver, sardines, clams and beef all have plenty. Vegetarians can stick with eggs and some cheeses, but vegans are at risk for vitamin B12 deficiency.
Another group at risk is people older than 60, for reasons medicine doesn't yet understand. In older men, this deficiency has been linked to a low sperm count and lazier sperm. In the hopes that the cure for abnormal sperm production is as simple as a B12 supplement, researchers have performed multiple studies on men with fertility issues, but unfortunately, the results have been inconclusive. There simply isn't enough scientific evidence yet to determine whether B12 supplements can fight male infertility.
Niacin (Vitamin B3)
You've already gotten acquainted with two of the B complex vitamins, B12 and B9. Get to know another important member: Vitamin B3, also known as niacin.
Niacin is notable when it comes to your sex life because it helps make sex hormones and improves your circulation (and we already learned why blood flow is so important when you're between the sheets). It also regulates things like sleep patterns -- and erectile dysfunction.
In June 2010, researchers were able to capture images of a protein responding to molecular signals from niacin that give information about oxygen levels in cells [source: University of Rochester Medical Center]. Studying this signaling could help us find new methods to treat erectile dysfunction in the future.
Supplements aren't necessary to keep you niacin-rich -- you almost always get enough from your diet, whether you're the king of beet recipes, a voracious red-meat eater or simply a drinker of milk.
The key to a healthy sex life (beyond, you know, relationship skills)? Getting to the grocery store -- and skipping the chips.
HowStuffWorks looks at a study linking time spent with childhood friends with improved outcomes in men's health.
- Iowa State University. "Folate Facts." September 2004. (March 12, 2011.)http://www.extension.iastate.edu/Publications/N3401.pdf
- Moynihan, Tim and Jane Kirby. "Taking folic acid can enhance fertility in men, researchers say." The Independent. March 20, 2008. (March 12, 2011.)http://www.independent.co.uk/life-style/health-and-families/health-news/taking-folic-acid-can-enhance-fertility-in-men-researchers-say-798387.html
- National Kidney and Urologic Diseases Information Clearinghouse. "What I Need to Know About Urinary Tract Infections." National Institute of Diabetes and Digestive and Kidney Diseases. August 2007. (March 12, 2011.)http://kidney.niddk.nih.gov/kudiseases/pubs/uti_ez/
- Nippoldt, Todd B. "Is 'herbal Viagra' safe?" Mayo Clinic. Feb. 2, 2010. (March 12, 2011.)http://www.mayoclinic.com/health/herbal-viagra/AN00702
- NYU Langone Medical Center. "Carnitine." February 2011. (March 12, 2011.)http://www.med.nyu.edu/content?ChunkIID=21450
- NYU Langone Medical Center."Male Infertility." February 2011. (March 8, 2011.)http://www.med.nyu.edu/content?ChunkIID=21723
- NYU Langone Medical Center. "Vitamin B12." February 2011. (March 14, 2011.)http://www.med.nyu.edu/content?ChunkIID=21679
- Office of Dietary Supplements, National Institutes of Health. "Dietary Supplement Fact Sheets." (March 12, 2011.)http://ods.od.nih.gov/factsheets/
- Reuters. "More Evidence Folic Acid Prevents Birth Defects." March 12, 2011. (March 12, 2011.)http://in.reuters.com/article/2011/03/11/us-folic-acid-idINTRE72A7OO20110311.
- Smith, Ian K. "Vitamin Overdose." Time. April 24, 2000. (March 12, 2011.)http://www.time.com/time/magazine/article/0,9171,996706,00.html
- University of Maryland Medical Center. A.D.A.M. "Sexual dysfunction." (March 8, 2011.)http://www.umm.edu/altmed/articles/sexual-dysfunction-000150.htm
- University of Maryland Medical Center. A.D.A.M. "Vitamin B3 (Niacin)." (March 14, 2011.)http://www.umm.edu/altmed/articles/vitamin-b3-000335.htm
- University of Maryland Medical Center. A.D.A.M. "Vitamin B12." (March 14, 2011.)http://www.umm.edu/altmed/articles/vitamin-b12-000332.htm
- University of Rochester Medical Center. "Vitamin B3 Controls Important Life Processes by Changing Shape in Response to Oxygen Level." June 4, 2010. (March 14, 2011.)http://www.urmc.rochester.edu/news/story/index.cfm?id=2889
- WebMD. "Understanding Anemia -- The Basics." (March 14, 2011.)http://www.webmd.com/a-to-z-guides/understanding-anemia-basics