Broadly, human exposures to ionizing radiation (on Earth) are considered beneficial for medical (diagnostic and/or therapeutic) exposures, but considered harmful for most other exposure scenarios (but with various exceptions, e.g., in radon hot spring bathing), at the level of exposed individuals. Over many generations, heritable (detrimental) effects may be harmful (no human evidence available hitherto, but if such effects exist) and revolution may be beneficial. There is little knowledge on health effects of human radiation exposure in space, but whether harmful or beneficial may depend on the needs and reasons for space travels.

Radiation is a prerequisite of life. Without radiation there is no photosynthesis. The only known life forms that can exist without direct radiation (or without consuming other, radiaton-based life forms) are extremophile bacteria that live in the deep sea. Those can exist due to the heat of so called "black smokers" in the deep sea and which are fed by thermal energy. The thermal energy is generated by radioactive decay in the inner earth. So again, radiation-based.

In this sense, radiation is never "harmful" in the big picture.

I have been working with radiation for about 50 years. I am a Nuclear Doctor and I have used nuclear radiation (gamma, beta and, quite recently, also alpha), on hundreds of patients. These patients benefited from these radiations to diagnose many diseases, even rare and complicated ones. The use then of beta and alpha radiation resulted in the resolution of many diseases (one for all thyroid carcinoma) or at least the resolution of serious symptoms such as eg. pain in bone metastases.

In my opinion, therefore, the radiation I mentioned is absolutely more beneficial than harmful, both in the short and long term. What you absolutely need to do is use them with appropriateness and prudence.

Your question contains the answer. "Radiation" is a vast domain, so the short answer is only this: both harmful and useful radiation, and useful at all times and forever in the future. ... or didn’t I understand something?

Life on earth is conditioned by radiation, radiation is not harmful as long as it does not exceed the possible limit of living things. Man is adapted to the natural radioactive conditions to which he is exposed on earth. It is not adapted to the radioactive conditions in outer space.

The level of natural radioactivity measured at the earth's crust varies in time and space. Natural radioactivity is influenced by the earth's internal radioactivity and cosmic radioactivity when it reaches the earth's surface. These values are valid only on planet earth.

Nancy Ann Watanabe

You do not seem to understand that microwave radiation is electromagnetic radiation. There is also beta radiation, alpha radiation, radiation of atoms, radiation of molecules, which are not electromagnetic radiation, and other radiation.

In the universe radiation is the main means by which mass-energy is transported over the greatest distances, and most quickly.

Electromagnetic radiation from the sun is the main way that energy is transported from the sun to the earth, and has enabled the life we know on earth to happen, and we are adapted to use or survive the amount and type of radiation that reaches us after filtering or absorption by the atmosphere, which is mainly infra red, visible and ultra-violet electromagnetic radiation. High energy particles and gamma rays and x-rays (the second two are electromagnetic radiation) are a natural radiation that comes from outer space or our own environment, that do not seem good for us but which we largely survive at the existing natural levels. Even ultra-violet is dangerous but our bodies have some protective mechanisms and are also able to harness some of it to make the main source of vitamin D in natural living conditions. Even natural visible and infra-red radiation are dangerous - they can overheat us - but we have a protection mechanism - we feel hot and move somewhere cooler or in shade.

Perhaps we need to distinguish radiations to see the harmful and the beneficial ones. In all, there are always a minimum permitted thresholds above which it is harmful.

Radiation is life. Without radiation the universe will not exist. However, ionizing radiation exposure must be controlled for life to be sustained.

Radiation is a fact of life. As to whether radiation is more harmful or beneficial in the long run, in my opinion, I think Moderation is key. Taking into account relevant guiding principles of the radiation in use.

Radiation gives the earth appropriate energy to rotate on its obit while keeping it stable by gravity. In this way, existence of lives get on on the earth.

The most popular answers contain opposite conclusions. This confirms the pointlessness of the question.

I guess that in the long rule, solar radiation in some cities like Barranquilla Co (200 days a year and 600 kV / h daily) will be more beneficial for industrial purposes, but the associated heat waves will be more detrimental to people's health.

Radiation is a prerequisite of life. Without radiation there is no photosynthesis. The only known life forms that can exist without direct radiation (or without consuming other, radiaton-based life forms) are extremophile bacteria that live in the deep sea. Those can exist due to the heat of so called "black smokers" in the deep sea and which are fed by thermal energy. The thermal energy is generated by radioactive decay in the inner earth. So again, radiation-based.

In this sense, radiation is never "harmful" in the big picture.

Vladimir A. Lebedev ,

I thank you very much for your answers; however, not all of us possess your high level of knowledge and expertise about the role of radiation in our universe. For example, I would not have assumed that, as you state, "Radiation is a prerequisite of life"; moreover, I, for one, did not know that "Without radiation there is no photosynthesis." This is fascinating new information you provide: "The only known life forms that can exist without direct radiation (or without consuming other, radiation-based lifeforms) are extremophile bacteria that live in the deep sea. Those can exist due to the heat of so called 'black smokers' in the deep sea and which are fed by thermal energy. The thermal energy is generated by radioactive decay in the inner earth. So again, radiation-based." However, I do not know whether or not all scientists would agree totally with your statement that "In this sense, radiation is never 'harmful' in the big picture"! Cordial regards.

I didn’t write any of this. These are quotes from not my answers. You are mistaken. I wish you all the best !.

The universe has been created from radiation, if we talk about ionizing radiation , which is energy and matter :alpha radiation is neutrons and protons, beta is electrons. These three elementary particles are the main constituents of existing matter , they are every where briefly said. Solar radiation is life giving and so on.

there are so many types of radiation in our universal but some of them most important for our life because they protect us from various disease and with help of radiation we can kill the different virus from environment as well as we use it for biological system such like electromagnetic radiation, cosmic radiation , ultraviolet radiation etc the

Radiation is an important factor to keep biological processes active, regulate activity of enzymes, regulate apoptosis, mitosis and, at some unusual point - necrosis, stimulate mutations. Radiation has influence on protein conformation, activate immune system. And many, many, many different purposes.

It is interesting to learn from everyone how long it is possible to declare well-known truths? ..

the end

Dmitri Popov ,

Thank you very much for your answer, which is informative from the perspective of health and general well-being or wellness!

Adnan Lahham ,

Thank you for reminding us of the role of radiation in the beginning, presumably when the universe was created ex nihilo.

Vladimir A. Lebedev ,

Yes, as you indicate, radiation will play a big role "in the end," when our sun develops into a red giant and engulfs Mercury, Venus, and, possibly, Earth.