These questions would seem more at home in new age circles, scorned by scientific thinkers. How can something as intangible as a thought or belief make physical changes in our bodies?
In a time of physical science, where only material forces are deemed as real, it would be forgiven to think this way.
However, we are no longer in that time.
Welcome to the crazy world of Quantum Physics.
Subatomic Particles
Many of us learned in school that atoms consist of particles called electrons, neutrons and protons. What High School science didn't teach us is that these are not the smallest particles. These can be split into even smaller particles that include borons, fermions and quarks.
It has been found that these smaller particles are not made of physical matter.
They are made of extremely powerful, invisible energy vortices.
So to work this backwards:
- atoms are made up purely of energy
- cells are made of atoms, which are energy
- organisms are made of cells, which are energy
... then organisms, such as humans, are pure energy.
That's right. You are not solid matter at all.
You are pure energy.
Sounds a bit Sci Fi? This is just standard quantum physics!
The Body's Energy Fields
As we are ultimately energy, people have their own energy field made of all the energy fields made by each cell.
Uses of Energy Fields in Medicine
Modern medicine regularly uses this energy radiation for treatment and diagnosis, both by reading the energies and manipulating them.
Energy Reading: It is standard practice in hospitals to read the energy given off by our body’s tissues and organs. Problems can be diagnosed by spotting energy differences between healthy tissue and diseased tissue.
Energy fields travel easily through the body allowing CT scans, MRIs and positron emission tomography (PET) scans to detect disease without having to cut people open.
Brain activity and tumours in the brain can be identified using sensors placed outside the skull during Electroencephalography and Magnetoencephalography. These read electrical or electromagnetic activity emitted from the brain inside the skull.
There have also been many studies showing the invisible forces of the electromagnetic spectrum can cause changes to our bodies.
Energy Manipulation: Brain behaviour can be altered by creating a magnetic field outside the head in treatment called Transcranial Magnetic Stimulation. This can be used to treat depression and to change behaviours in autism. [2]
Cell division, hormone secretion, gene regulation and nerve growth are just some of the elements that are affected by energies. These energies include microwaves, radio frequencies, the visible light spectrum, extremely low frequencies and acoustic frequencies [3-11].
What does this have to do with our thoughts and our health? First we need to understand a little about cells and how they work.
How Cells Work
Cells are incredibly clever little units. 
The key parts of a cell, for this discussion, are the membrane and the nucleus.
Cells are surrounded by a membrane that acts like a skin to protect the cell. This controls what substances come in and out of the cell. It also acts like a mini nervous system as it has millions of receptors that monitor everything around the cell. These receptors interpret messages and make decisions about the cell's behaviour [12].
The cell nucleus is where our DNA is stored. Our genes used to be thought to represent our blue print, dictating our physical characteristics, behaviours and any possible health conditions. It was thought that our genes were set in stone.
The work of Epigeneticists has blown this out of the water. They have discovered that genes are merely codes that give each cell its structure and functions.
Cell activity is not dictated solely by our genes but responds to the environment it is in [13]. This environment includes nutrition, stress and emotions. Genes can be turned on or off depending upon the environment of the cell and the environment of the organism, in our case, the human [14].
In view of this, illness or health is not a genetic issue but has more grounding in the emotional and physical environment we live in.
However, our responses to the environment are controlled by our perceptions which, in turn, are based on things we've been taught and our past experiences. They are not necessarily true or accurate. They are just thoughts, opinions, beliefs.
Thoughts and Beliefs
Thoughts are the mind's energy. 
As such, they can interact with our body's cells and activate or inhibit the cell’s function just as the medical devices can. They can turn our genes on or off.
An important study compared energy signals versus chemical signals to move information in and out of a cell. They discovered that energy signals are a hundred times more efficient in relaying information about the environment than physical signals such as hormones, neurotransmitters, growth factors [15]. The speed of electromagnetic energy signals is 186,000 miles per second, while the speed of a diffusible chemical is considerably less than one centimetre per second.
Thoughts are therefore an incredibly fast and efficient way of communicating with our bodies, to ensure our cells have the right information to behave in the way needed at that moment.
We have thoughts constantly, whether we are aware of them or not. Many thoughts come and go in a split second, however, our body picks up on all of them. As said earlier, many of these thoughts aren't necessarily accurate or factual but are our interpretation of the world around us.
More and more evidence points towards the importance of our thoughts. What we tell ourselves has a significant impact on the way our bodies work.
What does all this mean?
With this in mind, what is the impact on a person's body when they are told by the respected medical world that they have a condition that there is no treatment for and that they will only get worse, not better?
A symptom, such as pain, may develop initially through a chronic stress response. You go to the doctor who tells you it is caused by a worn joint, it is so worn they're amazed you're even walking. Obviously, they say, it will get worse the more you use it and every time you move you will feel pain.
So, on top of the existing chronic stress that caused the problem in the first place (this could be a whole range of causes – see Causes of Stress), you now have an additional stress response from the fear of the diagnosis, sadness over the life-style and dreams you have lost, guilt at not being able to do as much as before for your family ... and the list goes on. This is then compounded by the belief that this pain is a permanent, non-reversible condition and that you will physically deteriorate over time.
Think of the health impact of telling the cleaners their work made them healthy - their health improved. Reverse this and what do you get?
A self fulfilling prophecy.
The conclusion is simple: positive thoughts and beliefs enhance health, while negative thoughts and beliefs contribute to disease.
Our mind's energy needs to be shifted towards positive, health-giving thoughts. Negative, disabling, soul-destroying thoughts must be put to one side to enable us to thrive.
Let's just get this clear, I am in no way saying think happy thoughts and the world will be rid of all evils, illness will be no more and every one will love one another. Nice as this would be, this is just one factor in a large and complex jigsaw.
To have any hope of seeing the full jigsaw picture, though, we have to start finding the pieces and using them.
“We are the drivers of our own biology. When we understand this, we become masters of our fate, not victims of our genes” Bruce Lipton.
Connecting the Mind and Body for Health