  We use a bosonization approach to show that the momentum distribution
$n_{\bf{k}}$ of normal Fermi systems with sufficiently singular interactions is
analytic in the vicinity of the non-interacting Fermi surface. These include
singular density-density interactions that diverge in $d$ dimensions stronger
than $ | {\bf{q}} |^{- 2 (d -1)}$ for vanishing momentum transfer ${\bf{q}}$,
but also fermions that are coupled to transverse gauge fields in $ d < 3$.
