A sharp decline in deaths from malnutrition and diseases such as measles and tuberculosis has caused a shift in global mortality patterns during the past 20 years, according to a new report, with far more of the world’s population now living into old age and dying from diseases more associated with rich countries, such as cancer and heart disease.

The shift reflects improvements in sanitation, medical services and access to food throughout the developing world, and the success of broad public-health efforts such as vaccine programs. The results are dramatic: Infant mortality has declined by more than half between 1990 and 2010, and malnutrition, the No. 1 risk factor for death and years of life lost in 1990, has fallen to No. 8.

At the same time, chronic diseases such as cancer now account for about two of every three deaths worldwide, up from just more than half in 1990. Eight million people died of cancer in 2010, 38 percent more than in 1990. Diabetes claimed 1.3 million lives in 2010, double the number in 1990.

But while developing countries made big strides — the average age of death in Brazil and Paraguay, for example, jumped to 63 in 2010, up from 28 in 1970 — the United States stagnated.

U.S. women registered the smallest gains in life expectancy of all high-income countries between 1990 and 2010. The two years of life they gained was less than in Cyprus, where women gained 2.3 years of life, and Canada, where women gained 2.4 years.

The slow increase caused U.S. women to fall to 36th place in the report’s global ranking of life expectancy, down from 22nd in 1990.

“It’s alarming just how little progress there has been for women in the United States,” said Christopher Murray, director of the Institute for Health Metrics and Evaluation, a health-research organization financed by the Bill & Melinda Gates Foundation at the University of Washington that coordinated the report.

Rising rates of obesity among U.S. women and the legacy of smoking are among the factors contributing to the stagnation, he said.

As in 1990, Japan topped the life-expectancy list in 2010, with 79 for men and 86 for women. In the U.S. that year, life expectancy for men was 76 and for women, 81.

The research found wide variations in what’s killing people worldwide. Some of the most striking findings highlighted by the researchers:

• Homicide is the No. 3 killer of men in Latin America; it ranks 20th worldwide. In the U.S., it is the 21st cause of death in men, and in Western Europe, 57th.
• While suicide ranks globally as the 21st leading killer, it is as high as the ninth top cause of death in women across Asia’s “suicide belt,” from India to China. Suicide ranks 14th in North America and 15th in Western Europe.
• In people 15-49, diabetes is a bigger killer in Africa than in Western Europe (8.8 deaths versus 1 death per 100,000).
• Central and Southeast Asia have the highest rates of fatal stroke in young adults at about 15 cases per 100,000 deaths. In North America, the rate is about 3 per 100,000.
• Globally, heart disease and stroke remain the top killers. Reflecting an older population, lung cancer moved to the fifth cause of death globally, while other cancers including those of the liver, stomach and colon, are also in the top 20. AIDS jumped from the 35th cause of death in 1990 to the sixth leading cause two decades later.

The World Health Organization (WHO) issued a statement Thursday saying some of the estimates in the report differ substantially from those done by U.N. agencies, although others are similar.

All comprehensive estimates of global mortality rely heavily on statistical modeling because only 34 countries — representing about 15 percent of the world’s population — produce quality cause-of-death data.

Health experts from more than 300 institutions contributed to the report, which measured disease and mortality for populations in more than 180 countries. It was published Thursday in the Lancet, a British medical journal.

The one exception to the trend was sub-Saharan Africa, where infectious diseases, childhood illnesses and maternal causes of death account for about 70 percent of all illness. In contrast, they account for just one-third in South Asia and less than a fifth in all other regions.

Sub-Saharan Africa also lagged in mortality gains, with the average age of death there rising by fewer than 10 years from 1970 to 2010, compared to a more than 25-year increase in Latin America, Asia and North Africa.

The change means people are living longer, an outcome that public-health experts praised. But it also raises troubling questions. Behavior affects people’s risks of developing noncommunicable diseases such as cancer, heart disease and diabetes, and public-health experts say it is far harder to get people to change their ways than to administer a vaccine that protects children from an infectious disease such as measles.

Material from The Associated Press is included in this report.