Yes. Let $f$ be a eigenfunction of $\Delta$ with respect to $\lambda_1$. By multiplying a constant, we can assume that $\sup f - \inf f = 2$ (It can be found as $f$ is nonconstant). If $\inf f \geq -1$, we are done. If $\inf f < -1$, then $\sup f < 1$, and $h=-f$ satisfies $\inf h \geq -1$.