Why Do I Smell After Taking Vitamins?

People who have trimethylaminuria experience a buildup of a fish-smelling compound, called trimethylamine. In most people, this compound is processed with naturally occurring enzymes and is excreted in the urine. But, in people with the disorder, the enzyme is missing or deficient, so the fishy compound excretes in the breath and sweat as well. The result is a potent body odor that can be strong and somewhat offensive. People with trimethylaminuria often experience the fishy odor in response to intake of the B vitamin choline, which is present in many multivitamins and B-complex blends.

Vitamin B-1, commonly known as thiamin, can also alter your body odor if taken in mega doses. Some of the excess thiamin leaks out through the skin, which causes your body to smell. The recommended dose for this vitamin is 1.1 to 1.2 milligrams daily, but more is unlikely to cause serious health impact beyond the possible body odor.

The vitamin supplements may not be causing the odor, either. If you started taking the vitamins because your diet isn't as nutritionally sound as it should be, it could be your diet, not the vitamin, causing the odor. For example, if you rely heavily on processed foods -- especially ones high in sugar -- your blood may become overly sugary. This sugar, Dr. Debra Jaliman, a dermatologist and spokesperson for the American Academy of Dermatology, told the website Next Avenue, could cause changes in perspiration that interact with bacteria on the skin. This interaction sometimes causes an unpleasant odor.

A low-carb diet could also cause your body odor to escalate. These diets often push your body to burn fat at a rapid rate, in a state called ketosis, and may result in fruity-smelling sweat and urine. You may also notice an odor that resembles acetone, a common ingredient in nail polish remover, coming from your body.

Most people are best off getting their vitamins from whole foods rather than a supplement. So, instead of suffering with an unpleasant smell, clean up your diet. Consume a wide variety of fresh fruits, vegetables, whole grains, nuts, seeds, lean protein and low-fat dairy to get the nutrients you need. If you do find that even with dietary changes a fishy body odor persists, consult your physician for testing for trimethylaminuria.