In the process of developing higher states of consciousness the different layers of our inner existence are very gradually made accustomed to the unfiltered cosmic light conditions of the sun of our inner self. This is comparable to the natural precautions against sunburn, where our body has to prepare itself very gradually for the direct radiation of the sun, which is felt as aggressive. But going through these different filtering stations has also another practical advantage – for while traveling on this way the universal light of our inner sun of life is transformed by our intellect, our feeling and by our understanding into the quality of the cosmic, or more exact: our inner human forces intellect, feeling and understanding reveal to us in our inner universal light of life its cosmic qualities: where in the beginning unity dominated, now, after this, cosmic variety dominates.

Within a man with little development of consciousness nothing universal of his light of life reaches his body and mostly even not his mind any more during this mentioned process; for through the inadequate natural coordination of his inner human forces, the intellect, feeling and understanding initially had to extract so many components from this universal light in the interest of a more orderly function of their own, that already on the level of consciousness, that is, in the field of the mind, the cosmic was not perceptible any more.
That from such a situation no universal health can be derived – neither theoretically nor practically – is obvious.

Your first question was: “What disturbs this stream most – that is, what do I have to abstain from most, so that I do not get ill?”

The answer is: that, what is called „stress“ nowadays – in the most comprehensive manner – disturbs this stream of the inner light of life down to the field of neurophysiology most.
For not getting sick I therefore must abstain from stress most.

However, this is only the one side of supporting health. The more important method emerges from your second question: “What supports this stream most strongly – that is, what do I have to support most, in order to stay healthy?

For our health it is imperative that our inner light of life penetrates the different layers of our inner human forces. The specific, systematic and: successful reduction of stress is the first method, to make the different mentioned layers more permeable from the outside to the inside.
But without doubt the still more effective method is to increase the cosmic luminosity of our sun of life: its radiation. And the ancient practical plan for this is the path of meditation, or Yoga.

Meditation, or Yoga – meditation is the technology, or the path, and Yoga is the state of cosmic light permeability, which is achieved – bring about the activation of the radiation of our inner sun of life by intensifying the integration of intellect, feeling and understanding.

This integration also coordinates our consciousness as well as our thinking with our life breath – which lies at the basis of our breathing in and out as an immortal, standing and at the same time moving cosmic breath. This breath is already active before our birth.
In the moment of coordinating our mentioned three inner main human powers intellect, feeling and understanding with our cosmic life breath a kind of lightning is kindled in the sun of our self, which spreads out to the mentioned inner spheres down to our body using the aforementioned channels.