Lumix fz 28 reduced number of pixels

My FZ 28 is quite noisy in low light.
10 million pixels in a tiny sensor I guess causes the problem. Question is whether when selecting a reduced number of pixels the low light noise would be reduced ie are only, say, half the number of sensor receptors used when making the image file such that there willbe less interference between receptors? Or are all receptors used then half thrown away to save file space?
Thanks for any info.
Cheers
Jeff