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The paper deals with very weak solutions $u\in \theta +W_0^{1,r}\left(\Omega \right)$, $max\{1,p-1\}<r<p<n$, to boundary value problems of the $p$-harmonic equation $$\left\{\begin{array}{cc}-\text{div}\left(\right|\nabla u\left(x\right){|}^{p-2}\nabla u\left(x\right))=0,\hfill & x\in \Omega ,\hfill \\ u\left(x\right)=\theta \left(x\right),\hfill & x\in \partial \Omega .\hfill \end{array}\right.(*)$$ We show that, under the assumption $\theta \in W^{1,q}\left(\Omega \right)$, $q>r$, any very weak solution $u$ to the boundary value problem ($*$) is integrable with $$u\in \left\{\begin{array}{cc}\theta +L_{\mathrm{weak}}^{q^{*}}\left(\Omega \right)\hfill & \text{for}q<n,\hfill \\ \theta +L_{\mathrm{weak}}^{\tau }\left(\Omega \right)\hfill & \text{for}q=n\text{and}\text{any}\tau <\infty ,\hfill \\ \theta +L^{\infty }\left(\Omega \right)\hfill & \text{for}q>n,\hfill \end{array}\right.$$ provided that $r$ is sufficiently close to $p$.

We are interested in regularizing effect of the interplay between the coefficient of zero order term and the datum in some noncoercive integral functionals of the type $$𝒥\left(v\right)={\int }_{\Omega }j(x,v,\nabla v)\mathrm{d}x+{\int }_{\Omega }a\left(x\right){\left|v\right|}^2\mathrm{d}x-{\int }_{\Omega }fv\mathrm{d}x,v\in W_0^{1,2}\left(\Omega \right),$$ where $\Omega \subset {ℝ}^N$, $j$ is a Carathéodory function such that $\xi \mapsto j(x,s,\xi )$ is convex, and there exist constants $0\le \tau <1$ and $M>0$ such that $$\frac{{\left|\xi \right|}^2}{{(1+|s\left|\right)}^{\tau }}\le j(x,s,\xi )\le M{\left|\xi \right|}^2$$ for almost all $x\in \Omega$, all $s\in ℝ$ and all $\xi \in {ℝ}^N$. We show that, even if $0<a\left(x\right)$ and $f\left(x\right)$ only belong to $L^1\left(\Omega \right)$, the interplay $$\left|f\right(x\left)\right|\le 2Qa\left(x\right)$$ implies the existence of a minimizer $u\in W_0^{1,2}\left(\Omega \right)$ which belongs to $L^{\infty }\left(\Omega \right)$.