The energy healing experiments (by Gary E Schwartz; phd) is a fascinating book covering several attempted experiments devised to try and evaluate the actual effects of various forms of esoteric healing practices and philosophies.
One such experiment was to have several sealed test-tubes in a controlled environment. Each populated with a colony of the same microbes (I think it was some sort of bacteria but I don't recall exactly) and the same volume of sustenance.
Each test tube would have a person spend about twenty minutes a day, holding their hands over or near the tube and visualizing healing/supporting the microbe, Impeding/destroying the microbe, or doing nothing. At the conclusion it was found that the tube 'fed' with positive intentions had a significantly stronger colony/growth compared to the one being 'attacked'. And still somewhat more growth than the 'control/neutral tube. While the one that was attacked had less growth compared to both the 'healed' tube and also the control.
Now, the experiment was pretty ad-hoc, and I do not know how thoroughly the experiment was controlled or observed. So how significant such a result is can be described as ... thoroughly debatable. But not entirely without significance. And. Even then. These were small, isolated colonies in contained spaces with experienced energy-workers committing direct and focused effort on a known visible and present target. And what was achieved was a reduction. Not an elimination.
So up-scaling this to an entire personal environment with hundreds of invisible and unknown species numbering into literal hundreds of millions of individual microbes spread about every fathomable nook, cranny, crack, and space and one begins to understand the mountain of a task you are facing. ...Might as well shovel all the snow off mount-everest with a wooden spoon while you are at it.
Personal hygiene and healthy living would be far less effort and give far greater gains.