Dietary supplements are big business. Every year, millions of health conscious consumers spend billions of dollars on ginkgo biloba, noni juice, multivitamins, and other supposedly health boosting substances. But are dietary supplements really good for us? In too many cases, maybe not, according to a Consumer Reports study. The study singled out several suspect ingredients commonly found in dietary supplements that could be decidedly unhealthy. Aconite, for example, is an ingredient used in supplements meant to treat joint pain. But it’s also been linked to nausea and heart rhythm disorders.