7 Foods That Might Be Giving You B.O.

Sure, the smell of your last meal can linger around your house–for better or worse–but it can also change your smell.

What causes body odor? Not sweat itself, which has no scent–it's basically water and electrolytes. Instead, B.O. comes from a sort of chemical reaction.

"Most normal body odors are the interaction of skin bacteria with secretions in the area," says George Preti, PhD, a member of Monell Chemical Senses Center in Philadelphia.

Food might alter this smell because certain byproducts get secreted as our bodies break down what we eat, then react with the bacteria on our skin, explains John Swartzberg, MD, chair of the editorial board of the University of California Berkeley Wellness Letter.

There's not a huge amount of scientific evidence pointing to which foods are the worst offenders, but there's enough anecdotal evidence to give us a sense of what kinds of foods find their way into our body odor.

Here's what we know.

Garlic

Make these delicious potatoes for comfort food-made-healthy. In this video, find out how you can whip up a batch of creamy garlic mashed potatoes the whole family will love.

Onions

Eating onions is equally ill advised if you want to make a good first impression, and for the same reason as garlic: Onions also break down into sulfur compounds.

"Many of these volatile sulfur compounds have a high odor impact and can be detected at very low concentrations," says Preti, who is also an adjunct professor of dermatology at the University of Pennsylvania School of Medicine. In other words, a little goes a very long way.

It's sometimes hard to distinguish between garlic or onion breath and garlic or onion body odor, Preti adds.

Cruciferous veggies

Cabbage, bok choy, broccoli, and Brussels sprouts–among other cruciferous produce–also contain ample amounts of sulfur, says Kristen Smith, RDN, a spokesperson for the Academy of Nutrition and Dietetics.

A lot of the evidence for cruciferous vegetables contributing to body odor (through your breath, sweat, or flatulence) is anecdotal, adds Smith.

Regardless, there's a strong argument for eating these foods anyway. They have a lot of fiber and contain plenty of beta-carotene along with vitamins C, E, and K as well as folate. In addition to being good for general health, there's some evidence they may also help prevent certain types of cancer.

Meat

Here's another reason to limit the amount of meat, especially red meat, you ingest–particularly if you're a man looking for love.

In a small study, researchers randomized a group of 17 guys to either eat meat or abstain for two weeks. Then they switched groups. Women analyzed body odor from the men's armpits at the end of each session, saying that the body odor of the men when on vegetarian diets was "more attractive, more pleasant, and less intense."

"It's mostly anecdotal, but I wouldn't be surprised," Dr. Swartzberg says, if the link panned out in future research.

Alcohol

Certainly excess amounts of alcohol can be detected on your breath, hence the roadside breath tests that can tell if you're over the legal driving limit or not.

What you may not know is that alcohol can also emanate off your skin.

"The alcohol is metabolized in the liver and broken into acetaldehyde that goes through your lungs into your breath, but it also gets to the pores," Dr. Swartzberg explains.

One or two glasses of wine probably isn't going to make you reek, but a few too many (not good for your health anyway!) could. "It's dose-dependent and individually based," says Smith.

Fish

Eat more fish and reap the rewards: youthful skin, improved memory, and healthy heart.

Asparagus

Asparagus doesn't contribute to body odor so much as it alters how your urine smells after you eat it. Most everyone produces the stinky chemicals that are excreted in urine as their bodies break down asparagus, but interestingly, not everybody can smell the resulting odor.

"Some people just can't smell it," says Dr. Swartzberg. "They don't have the receptors in their olfactory bulbs."

About 8% of people don't produce the offending odor and 6% can't smell it, according to Monell Center research.

What spells the difference? Just like so many other things, genetics.