Nuclear limits on nonminimally coupled gravity

We explore alternate theories of gravity where the gravitational term in Lagrangian $\frac{R}{8\pi G}$ is replaced by a function $f_1(R)$ and matter multiplied $f_2(R)$. argue that nuclear physics can provide strong experimental constraints on such theories. In particular using energy conditions pressure $^4$He nucleus, for $f_1(R)=\frac{R}{8\pi $f_2(R)=1+\lambda R$, we find limit $|\lambda| < 5\times 10^{-12}\, \hbox{m}^2$, more than thirty orders magnitude stronger previous limit.