If a product states it is manufactured in the USA, does that also mean the ingredients came from the USA as well?

NO. for Christmas, i bought several candy canes that had M&M candy inside. looking at the label on the plastic candy cane, i noticed this writing: plastic cane made in China, candy contents USA.

If it says “assembled in the US” the answer is no, if it says “Made in USA” the answer is yes.

If the components are imported, a label should say something like “Made in USA of U.S. and imported parts.”

For details, here is the Federal Trade Commision’s guide ’Complying with the Made In the USA Standard’

Vitamins may be different. The Food and Drug Administration (FDA) has rules about dietary supplements, I do not know it they rule on “Made in USA”.

This is from the Federal Trade Commission guidelines:

“Where a product is labeled or otherwise advertised with an unqualified “Made in USA” claim, it should contain only a de minimis, or negligible, amount of foreign content. Although there is no single “bright line” to establish when a product is or is not “all or virtually all” made in the United States, there are a number of factors that the Commission will look to in making this determination. To begin with, in order for a product to be considered “all or virtually all” made in the United States, the final assembly or processing of the product must take place in the United States. Beyond this minimum threshold, the Commission will consider other factors, including but not limited to the portion of the product’s total manufacturing costs that are attributable to U.S. parts and processing; and how far removed from the finished product any foreign content is.”

@Harp Great answer!

Thanks everyone for your insight.