A wide-ranging new global health study published in the medical journal The Lancet and funded by the Bill & Melinda Gates Foundation identifies the key risk factors for premature disease-related death worldwide: high blood pressure, poor diet, and tobacco use. In fact, poor diet alone is a risk factor for one in five global deaths, according to the research.
The massive new health report (in fact, a series of five separate ones) is part of an ongoing project called the Global Burden of Disease study (GBD). It collects mortality information from every nation and projects metrics like years of life lost and early death risk due to a disease or lifestyle and environmental factors.
One bit of good news? The world is living longer and better. "Overall, the findings show that the world is becoming healthier, but progress is uneven. People are living longer, but with more disease," wrote Lancet editors in commentary accompanying the research.
For instance, the number of deaths among children under five fell below five million for the first time ever, the researchers found, though overall both men and women around the world are living longer: Worldwide life expectancy rose to 75.3 years for women and 69.8 years in men in 2016.
Infectious disease deaths have decreased almost across the board since 1990, and death rates across all age groups have plunged in the last 50 years. (On a more sour note, the Centers for Disease Control found that U.S. life expectancy actually dropped in 2015 for the first time since 1993; data on 2016 trends will be released at the end of this year.)
But more than 72% of all 2016 deaths were caused by non-communicable diseases such as cardiovascular or heart disease, cancer, diabetes, lung disease, and Alzheimer's disease. The prevalence of Alzheimer's is expected to explode across the world as people continue to live longer.
One striking aspect of the study is how it pinpoints risk factors like smoking and diet, which are linked with all sorts of medical conditions like obesity-related diabetes, ischemic heart disease, stroke, and cancer. While the rise of sugary foods and red meats isn't considered healthy, an even bigger problem is malnutrition. Environmental factors like poor air quality also play a role in cancers and chronic obstructive pulmonary disease (COPD), a severe lung condition.
Going forward, researchers conducting the Global Burden of Disease study say they will expand their research to suss out the effects of phenomenon like climate change on global health.