Physicist Albert Einstein proved this with his famous equation E= mc2 or in other words Energy = mass multiplied by the speed of light squared.
And since everything is indeed made up of energy, solid matter simply being a denser form of energy, then the matter that makes up the physical body is very much effected by the energy that surrounds it and run through it. It is simple physics.
Even though what we call matter feels solid, it isn't. It is mostly empty space and between those empty spaces are energetic forces, such as electromagnetic fields, that interact and bring things together or push things apart. And then when you get into particle physics, that's when things really get crazy!
We are fundamentally energy, this is why Energy Medicine works at a more fundamental level than a physical based medicine. This is also why if you fix something on a physical level, but the energy is still off, the physical problem will often return.
Other than traumatic injury, disease and discomfort always shows up on an energetic level first. If you can catch it there before it progresses to a physical level, it is much easier to correct.