After she completed her education at Monmouth College, Nierenberg joined the Peace Corps as a volunteer in Dominican Republic and worked with farmers and urban school kids. Since then, she has been working to highlight how the food system can become more sustainable. Following her volunteer work in the Peace Corps, she matriculated at Tufts University and then joined Science and Environmental Health Network as an intern. Later on she joined Worldwatch Institute. According to Nierenberg, she has been focused on raising awareness about food quality and availability because she "is obsessed with food." She wants "to know what she’s having for dinner at lunchtime." She is a reviewer for the Africa Chapter for the Intergovernmental Panel on Climate Change WGII AR5 First Order Draft and serves on the Advisory Group for the Zero Hunger Partnership, along with Sir Gordon Conway and Heifer International President Pierre Ferrari. In 2013, she joined the Young Professional's Platform for Agricultural Research for Development Steering Committee. Nierenberg is also a member of the UN Environmental Programme's Economics of Ecosystems and Biodiversity Steering Committee.
Worldwatch Institute
In 2001, Nierenberg joined the Worldwatch Institute as its Food and Agricultural Senior Researcher, where she managed several research projects on emerging infectious diseases related to the food system, gender and population, climate change and agriculture, the global meat economy, and innovations in sustainable agriculture. In 2009 she co-founded the Nourishing the Planet project housed at the Worldwatch Institute and became its director. This post involved overseeing environmental research, communications and development for the Nourishing the Planet project, as well as leading the Nourishing the Planet Advisory Group. As part of this role, Nierenberg spent 18 months in Sub-Saharan Africa, looking for solutions to poverty and hunger in 30 different countries. While working there, she managed a grant of US$1.34 million to assess the state of agricultural innovations. Nierenberg produced State of the World 2011 with the help of 60 authors from all over the world. She also organized The State of the World Symposium in January 2011. She left Worldwatch Institute and Nourishing The Planet in 2012.
Nierenberg has written extensively on gender and population, the spread of factory farming in the developing world, and innovations in sustainable agriculture. She has also written for The Wall Street Journal, The New York Times, the Chicago Tribune, USA Today, The China Daily. The Washington Post, Le Monde, Bloomberg Businessweek, MSNBC, Al Jazeera, the Australian Broadcasting Corporation, the International Herald Tribune, BBC, MSNBC, Fox News, CNN, The Guardian, The Telegraph, Voice of America, the Times of India, and the Sydney Morning Herald. Nierenberg's first book was titled Correcting Gender Myopia: Gender Equity, Women's Welfare, and the Environment and was published by the Worldwatch Institute in 2002. In 2005, she wrote Happier Meals: Rethinking the Global Meat Industry, which is a paper that presents the effects of the growth of factory farming, cataloging the harmful effects it can have on the world, especially in developing countries. In 2012, she wrote Eating Planet 2012, presented during an event at the Literature Festival in Mantua in September. In partnership with the James Beard Foundation, Nierenberg and Food Tank publish an annual Good Food Org Guide, a directory of non-profit organizations working for a better food system
Writings
Correcting Gender Myopia: Gender Equity, Women's Welfare, and the Environment
Happier Meals: Rethinking the Global Meat Industry
State of the World 2011: Innovations that Nourish the Planet
Eating Planet–Nutrition Today: A Challenge for Mankind and for the Planet
17 Big Bets for a Better World
Letters to a Young Farmer: On Food, Farming, and Our Future
Eating Planet 2016
Food and Agriculture: The Future of Sustainability
She has also written on sustainable agriculture, in The Guardian, Bloomberg Businessweek, and the Huffington Post. and has had opinion-editorials published in the largest circulating newspapers in 40 states and also The New York Times, The Wall Street Journal, USA TodayThe China Daily. She routinely appears in major broadcast media including MSNBC, Fox News and Al Jazeera.