Overview Certain supplements can affect the way your body smells and give off a distinct, unpleasant odor. Sometimes taking a normal dose of a particular supplement can cause you to have body odor, but other times body odor only occurs if you’ve taken too much of a particular supplement. If you notice that your supplement is causing you to smell bad, talk to your doctor about discontinuing that particular supplement. Garlic Fresh garlic can cause body odor and bad breath, and the same is true for garlic supplements. These supplements often are made with fresh or dried garlic powder, which causes the supplements to have a similar effect to the real deal. Garlic supplements are sometimes used to help treat high blood pressure, prevent atherosclerosis and to reduce the risk of developing certain cancers, such as rectal, colon and stomach cancers. Garlic supplements, however, should not be substituted or used in place of traditional medications. Talk to your doctor before you begin taking any supplements to treat medical conditions. Omega-3 fatty acids Omega-3 fatty acid supplements are sometimes used to help prevent the spread of solid tumors and to inhibit the growth of certain cancers, such as colon, pancreatic and prostate cancers. Omega-3 fatty acids also are used to help ward off cardiovascular disease and prevent fatal heart attacks. These supplements contain anti-inflammatory properties, making them useful in the treatment of inflammation associated with arthritis, eczema and other health conditions. They’re often made from fish oils and oils extracted from beans, such as navy beans, soybeans and great northern beans. These supplements can cause your breath and body to have a fishy smell, even when taken at the correct dosage. Carnitine Your body produces carnitine on its own, via the liver and kidneys, and it is stored in the brain, heart, skeletal muscles and sperm. Typically, your body can make all the carnitine it needs, but certain medical conditions can inhibit the production and storage of carnitine. Certain medications also cause this to happen, which might make it necessary to take a carnitine supplement. A rare side effect of taking carnitine supplements is body odor; other rare side effects include increased appetite and body rash. Do not take these supplements without your doctor's approval, because they can interfere with some medical conditions. Choline Your body can manufacture choline on its own, notes the Linus Pauling Institute, but certain conditions and medications can make it difficult for your body to produce this nutrient. Choline is required for the body to remain healthy. Consuming high doses of this supplement, typically 10 to 16 grams a day, can cause a fishy body odor and increased sweating. Adults only require 3.5 grams of choline per day.