{'fraction_non_alphanumeric': 0.030107526881720432, 'fraction_numerical': 0.02007168458781362, 'mean_word_length': 4.989270386266094, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 1, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
The globalization of nonalcoholic fatty liver disease: Prevalence and impact on world health

As far as the scientific community can tell, the first prokaryotic cells emerged on an inhospitable Earth 3.8 billion years ago. The first mammalian fossils date to 200 million years ago and those of Homo sapiens to a mere 200,000 years ago. The human transition from existence exclusively as hunter-gatherers to agriculture-based civilizations began less than 12,000 years ago. Until a blink of an eye ago in biological terms, the ability to find enough food to survive was inconsistent and unpredictable. For several decades we have been producing enough calories at low enough cost for mass overnutrition to occur. Inexpensive grains, especially corn, have translated into inexpensive sugars and, simultaneously, inexpensive animal meat and fat. The US Department of Agriculture’s Economic Research Service estimates that caloric intake per capita in the United States is 2700 calories/ day, 800 calories/day above that consumed in 1950 (http://www.ers.usda.gov/data-products/food-availability(per-capita)-data-system/.aspx). The excess of calorie production and consumption is a global phenomenon (Fig. 1). The increase in daily caloric consumption is more than enough to explain the global epidemic of obesity. The most recent analysis by the World Health Organization reports that worldwide obesity has more than doubled since 1980. Globally, about 2 billion (39%) adults are overweight and over 600 million (13%) are obese. Most of the world’s population lives in countries where the consequences of excess nutrition kill more people than undernutrition. The burden of obesity is uneven in geographic terms, with more than half of the world’s obese living in just 10 countries. In the United States, the most recent National Health and Nutrition Education Survey reports that two-thirds of adults are overweight or obese and over 1 million individuals have a body mass index >60 kg/m. In this issue of HEPATOLOGY Younossi et al. present the results of a remarkable study that estimates the global prevalence, incidence, progression, and outcomes of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), bringing together more than 700 individual reports from around the world published between 1989 and 2015. The work has resulted in a new and clearer picture of the worldwide burden of NAFLD and NASH. The results should shape our thinking and approach to fatty liver disease. In a world beset by a litany of critical health challenges, concern about one of the consequences of overnutrition may seem quaint and, probably, transient. The study by Younossi et al. points to a different reality and merits detailed consideration of its three primary conclusions.