Photographer Gregg Segal travelled the world to document children and the food they eat in a week. Partly inspired by the increasing problems of childhood obesity, he tracked traditional regional diets as yet unaffected by globalisation, and ironically, found that the healthiest diets were often eaten by the least well off. (Photo by Gregg Segal/The Guardian)

A woman dressed up for Halloween travels on a Metro train in São Paulo, Brazil on October 30, 2017. (Photo by Cris Faga/Rex Features/Shutterstock)

People cheer as the ball drops at midnight in Times Square on January 1, 2015 in New York City. An estimated one million people from around the world are expected to pack Times Square to ring in 2015. (Photo by Andrew Theodorakis/Getty Images)

Fireworks explode over Elizabeth Tower housing the Big Ben clock in London. (Photo by Kirsty Wigglesworth/Associated Press)

Vehicles are burning as thousands of people take to the streets during the May Day demonstrations on May 1, 2018 in Paris, France. This month celebrates the 50th anniversary of May 68 when France seen millions of students and striking workers, come onto the streets in demonstrations that changed the country. (Photo by Jeff J. Mitchell/Getty Images)

Fireworks and light effects illuminate the night sky from the Taipei 101 skyscraper during New Year's Eve celebrations in Taipei, Taiwan, 01 January 2019. (Photo by Ritchie B. Tongo/EPA/EFE/Rex Features/Shutterstock)

Police officers detain an opposition protester during a May Day rally in Saint Petersburg, Russia on May 1, 2019. Labor Day or May Day is observed all over the world on the first day of the month of May to celebrate the economic and social achievements of workers and fight for laborers rights. (Photo by Igor Russak/Reuters)

A demonstrator is detained during May Day rallies in Santiago May 1, 2013. (Photo by Ivan Alvarado/Reuters)