They're both good as long as you know the EXACT nutritional content. By that I mean that a lot of brewer's yeast has salt added so check the sodium content. Wheat germ is also good as long as you know everything that's in it (carbs/protein/fat/sodium). As long as you know what's in your food then you can tailor your diet to suit. Not everyone is allergic to wheat!!!
Barring all of the above you might consider a trustworthy multi B-vite supplement.