Body odor isn't always about poor hygiene -- sometimes people have disorders or nutrient deficiencies that cause them to have an excessive, unpleasant smell. Not getting enough of a certain vitamin, such as B-12, can cause some people to have excessive, odorous gas -- but not necessarily an unpleasant body odor. Mineral deficiencies, particularly of zinc and magnesium, are more likely to cause body odor.
Zinc is not a vitamin but a mineral. One of its major functions is to break down carbohydrates and help cells clear out waste. A diet insufficient in zinc may deter this detoxification and cause body odor. Get zinc from oysters, beef, pork, lamb and dark-meat chicken. Fortified whole grains, nuts and legumes are other good sources.
Another mineral, magnesium, can also have an effect on your intestinal flora and body odor. A magnesium deficiency doesn't mean you'll develop body odor, but consuming foods rich in this mineral can help you deodorize more efficiently, according to research done by Dr. Pierre Delbet way back in 1928.
Foods such as dark chocolate, bran, coriander, almonds, cashews and tahini are rich in the mineral.
Riboflavin and Enzymes
If you have an unpleasant fishy odor constantly, even without eating a lot of seafood, you may suffer from the condition trimethylaminuria. Missing enzymes prevent you from properly processing a compound called trimethylamine that you get through your diet, so the smell releases in bulk in your sweat, urine and breath. Riboflavin, or vitamin B-2, has been shown in preliminary research to potentially help restart enzyme activity in patients with trimethylaminuria.
Again, a deficiency may not have caused the disorder, but extra riboflavin in your diet, along with reduction of trimethylamine-containing foods, such as cruciferous vegetables and seafood, could help. Find riboflavin in dairy, eggs, lean meats and nuts.
Other Dietary Interventions
You may not have a specific vitamin deficiency that causes your body odor, but dietary intervention could help clean up your scent. Fresh green plants, particularly parsley, kale, spinach and wheatgrass, contain lots of chlorophyll -- the compound that makes them green -- and may deodorize your body. Citrus juice, particularly from lemons and grapefruit, contains acid that flushes water quickly through your system; the fiber in these fruits also moves the contents of your digestive tract more quickly, so food has less time to ferment and cause odor.