The planets can only effect us in two ways. Gravity and electromagnetically, through light. The light is far too dim to even change a single base pair of DNA, and nowhere near strong enough to have any affect on neurons.

Perhaps there's more than this though....

The planets do emit EM, which we can imagine as ripples in a pond... Depending on their relative positions (and frequencies) then the EM radiation on Earth, will vary as the waves interfere.
The whole of space around the solar system is filled with interference-patterns, like standing-waves, from the planet's emissions, and as things move through space, and in orbit, those will change.

It's not beyond the realms of possibility that these EM standing-wave interference patterns could have an effect on humans.

We'll never get rid of superstition if we just replace one with another... Any blind belief is a superstition.

Scientific enquiry can determine the facts though, and then no opinions would be needed.
At the moment, science hasn't really done that, as far as I know. It just pretends the ideas are 'preposterous', and doesn't investigate... It seems most unscientific.