The United States is "deeply troubled" by the conditions of prisoners in Cuba.

The United States on Tuesday urged Cuba to free two men who Amnesty International has called "prisoners of conscience," saying their imprisonment exemplifies how the Cuban government continues to silence its citizens' peaceful opposition.
..."We call on the government of Cuba to release all political prisoners immediately," the U.S. State Department said, adding that it was "deeply troubled" by reports that Urquiola was on hunger strike and in a critical medical condition.

This concern for prisoners in Cuba doesn't extend to ALL prisoners in Cuba. Our concern doesn't extend to prisoners in Gitmo.

A detainee on hunger strike at Guantánamo Bay has accused officials of a sudden change in practice that could result in him starving to death.
Khalid Qasim, held at the prison for 15 years without charge or trial, told his lawyer that doctors stopped force-feeding him and another inmate three weeks ago, and are no longer monitoring their medical condition.

“They have decided to leave us to waste away and die instead,” Qasim, 40, told his lawyer by phone for an article published by the Guardian.

Of the 41 men remaining at Gitmo, 31 are being held in indefinite wartime detention without trial. In other words, they are political prisoners.
The United States is also worried about prisoners going on hunger strikes in Russia.

"The case of Oleg Sentsov is emblematic of the fact that in Russia today people can go to jail for peaceful resistance," said Tanya Lokshina, the Russia program director at the Human Rights Watch office in Moscow. "Russia is in fact swept up in the worst human rights crisis since the fall of the Soviet Union, and that is something we cannot possibly ignore, no matter how much of a success the World Cup itself is."

It certainly is concerning when a prison system gets so bad that the prisoners have to go on hunger strikes.
These hunger strikes have happened just in 2018:

Kansas prisoners on hunger strike against CCA’s inhumane conditions
Hunger strike at Santa Clara County jail enters day 10
45 inmates at north Texas prison on hunger strike
17 Huntsville prisoners on hunger strike after lockdown
Norfolk inmate starts hunger strike over water
Florida Prisoners Prepare to Strike, Demanding an End to Unpaid Labor and Brutal Conditions

That's only what I could find on a Google search.

Just like our massive, oversized prison system, prisoner protests are massive.
In 2016, over 24,000 prisoners in 24 states took part in a strike.

The issues behind the prison strike included unfair use of prison labor, poor wages, and unsatisfying living conditions.[3] The main goal of the strike was to end the alleged prison slavery to which inmates are subjected.[4] According to the 13th Amendment in the Constitution of the United States of America, people convicted of crimes can be formally enslaved.[5]

Despite the high number of striking prisoners, the strike received little mainstream media coverage

A strike by slaves against slavery. No wonder the news media ignored it.

In 2013, over 29,000 inmates went on a two-month hunger strike in protest California's use of solitary confinement practices.
You probably didn't read about that one either.

The U.S. prison system has the world’s highest incarceration rate per capita. Currently, one in every 38 Americans is under the control of the corrections system.

The U.S. has more jails than colleges.

The tiny state of Rhode Island has more prisoners than the entire nation of Costa Rica.

Worst of all, of the 2.3 million people in U.S. jails at any time, most have not been convicted. They are awaiting trial.