Don't tell anyone, but I've been secretly adding soylent to my husband's shakes.
Why have you been secretly doing that?
He's so unhealthy, and I don't like it. He smokes and drinks too much.
You shouldn't be hiding that you're adding something to his food. Have you thought about being open and honest about the situation with him?
No, I'm afraid that if I tell him he won't want to take it any more, and he'll become even less healthy.
I really think you should tell him that you're worried about his health. Maybe he doesn't realize that he's been partaking in some unhealthy habits, and if you let him know then it will be the wakeup call that he needs.