One of the industriesy that haves developed the mostgreatly during the past decade has been the medical oine.

removing unnecessary joining words gets to the point of the sentence and sounds more mature

Thanks to several discoveries realized by researchers working in this field, many people now live longer and better now. lives.¶

realized doesn't fit this context well, sounding a little unnatural.

One of the industries that haves developed the most during the past decade has been the medical oneindustry.

Thanks to several discoveries realized by researchers working in this field, many people live longer and better now. ¶

This essay will discuss the positive and negative aspects of improved healthcare and will show evidence onf the predominance of advantages over disadvantages. ¶
¶
¶

Although maintaining a developed healthcare system often means an expansion of costs borne by governments, it allows people to be more productive during a greater part of their lives.

By ensuring a good level of health condition tofor each citizen, it is possible to build an active and efficient community.

Another advantage of increased life expectancy regardconcerns the economic helpaid that elderly people usually provide to the younger generation, as they usually are the ones that have more savings.

With regard to the disadvantages, economists often say that longer lives bring toresults in a generally higher level of unemployment.

If governments are in charge tof provideing a monthly pension to the elderly, the increase in the number of people to whom retirement must be paid could represent a problem.

Moreover, some important resources on the planet are limited, and the increase of the population increase caused by a decrease in the rate of dedeath rathe could cause starvation periods. ¶
periods of starvation.¶
¶

Even if afurther development of the healthcare system will bring to some disadvantages, it is evident that by handling the increase in life expectancy and the consequent increase in population in the right way, countries can obtain more positive than negative effecresults.

One of the industries that haves developed the most during the past decade has been the medical one.

Needs to be "has" instead of "have" in this instance.

Thanks to several discoveries realizedmade by researchers working in this field, many people live longer and better now. ¶

I'm nitpicking, but it's unusual to use the term "realized" in relation to scientific discoveries. Better to use the term "made".

This essay will discuss the positive and negative aspects of improved healthcare and will show evidence onf the predominance of advantages over disadvantages. ¶
¶
¶

Also unusual to see

Although maintaining a developed healthcare system often means an expansion of costs borne by governments, it allows people to be more productive during great part of their lives.

Past tense of the verb "to bear", which someone else already pointed out.

By ensuring a good level of health condition tofor each citizen, it is possible to build an active and efficient community.

You "ensure" something "for" someone else, not "to" someone else.

Also you didn't need to use "health condition", as it is sufficient to simply write "health".

You could also have used "By ensuring good health for each citizen...".

With regard to the disadvantages, economists often say that longer lives bring to a generally higher level of unemployment.

If governments are in charge tod with provideing a monthly pension to the elderly, the increase in the number of people to whom retirement must be paid could represent a problem.

Moreover, some important resources on the planet are limited and the increase of the population caused by a decrease in the rate of death could cause starvation periods. ¶
periods of starvation.¶
¶

There is nothing wrong with "starvation periods" as far as I'm aware, but "periods of starvation" sounds better to my ear.

Even if a development of the healthcare system will bring to some disadvantages, it is evident that by handling the increase in life expectancy and the consequent increase in population in the right way, countries can obtain more positive than negative effects.

Although maintaining a developed healthcare system often means an expansion of costs borne by governments, it allows people to be more productive during greata large part of their lives.

past tense of to bear

By ensuring a good level of health condition to each citizeneach citizen is in good health, it is possible to build an active and efficient community.

With regards to the disadvantages, economists often say that longer lives bring to a generaltend to bring a higher level of unemployment.

If the governments are in chargwere to provide a monthly pension to the elderly, the increase in the number of people to whom retirement must be paid could represent a problem.

Moreover, some important resources on the planet are limited and the increase of the population caused by a decrease in the rate of dedeath rathe could cause starvation periods. ¶
periods of starvation.¶
¶

Even if a development of the healthcare system will bring tos some disadvantages, it is evident that by handling the increase in life expectancy, and the consequent increase in population in the right way, countries can obtain more positive than negative effects.