  The correction to the hydrogen Lamb shift due to the proton electric and
magnetic polarizabilities is expressed analytically through their static
values, which are known from experiment. The numerical value of the correction
to the hydrogen 1S state is $ - 71 \pm 11 \pm 7$ Hz. Correction to the H-D
1S-2S -- isotope shift due to the proton and neutron polarizabilities is
estimated as $ 53 \pm 9 \pm 11$ Hz.
