What vehicle you use and what you invest it in are different questions. You could put your whole 401k in JNUG (a 3x-leveraged gold miners ETF that will regularl

What vehicle you use and what you invest it in are different questions. You could put your whole 401k in JNUG (a 3x-leveraged gold miners ETF that will regularly have 20% up/down days). So 401k is very good advice, but then you have to determine what your 401k is invested in.