An Indonesia-based human rights researcher says malnutrition is widespread throughout Papua as imported foods have shattered traditional diets.
West Papuans had long lived off traditional Melanesian staple foods such as sago, sweet potato and traditional pork, but these had been increasingly replaced by rice and instant noodles.
This comes as Indonesian health officials responded to a health crisis in Papua province's Asmat district where a deadly outbreak of measles had been exacerbated by malnutrition.
Papuan police last week said there were more than 10,000 malnourished people in Asmat.
Andreas Harsono of Human Rights Watch said he has travelled throughout the region over the past two decades and seen the diets change for the worse.
"I see it all over Papua, not only in Asmat," he said.
"Their staple diet changed dramatically. Nowadays I see them consuming rice. Why? Rice is coming from their national government as their main diet."
Mr Harsono said that in Asmat people were also consuming less of the traditional sago as land was being used up for palm oil and mining.
He said he used to see a lot of sweet potato in Wamena in the Highlands, but rice was now more plentiful there too.
Meanwhile, government and military health teams vaccinating against a range of diseases had been dispatched to the district of Asmat after a measles outbreak which has killed at least 60 local children.
An Indonesian health official with one of the teams Jane Soepardi told RNZ Pacific many of the children she visited last week had zero immunity.
Mr Harsono said the government had been quite speedy in getting to affected areas but that the death toll underscored Jakarta's neglect of Papuans' basic health rights.
According to him, Indonesia's belated vaccination drive in Papua was not a long-term solution to health problems in Papua.
"The question is without a programme and routine vaccinations, continued vaccinations, what will happen next year, what will happen two years from now?" he said.
"I'm afraid that without a change of the government approach in the area in Papua, it is going to be repeated again."
Andreas Harsono said restrictions on access to Papua should be lifted so it could receive international assistance.