Could anything severe happen to a person that decides to only eat vegetables and nuts forever more?

Could anything severe happen to a person that decides to only eat vegetables and nuts forever more?
And does so...

?

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+1 y
Just wondering, don't go tearing my head off over some supplements, more protein, vitamins... and so on. o. O
Could anything severe happen to a person that decides to only eat vegetables and nuts forever more?
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