Heroes are normally the stuff of mythology. But for Tithiya Sharma, whose journey to find them has taken 18 months, consumed three passports and spanned 32 countries across five continents, heroes are part of everyday life.

From prostitutes in Thailand to feminists in Israel and doctors in Congo, Sharma has spent the past year looking for 100 inspirational figureheads, community leaders and social workers.

The only requirement? That each of these heroes is changing the future of their countries, from the clean boulevards of the west to the most under-privileged and conflict-ridden corners of the developing world.

Calling her quest the 100 Heroes Project, the New Delhi-born former journalist left the newsrooms of Mumbai, formerly Bombay, in May 2010 and just this month touched down in South America, on one of the final legs of her global tour.

"I'd become so used to being a journalist in India, making really good money, renting a fancy apartment in the most expensive part of Bombay, going to the same pub every weekend," says Sharma, 29, en route to meet her latest hero in Rio de Janeiro's notorious City of God favela.

"It was such an easy trap to fall into and I knew that if I was going to make a change it had to be something really drastic. So I quit my job, sold all my stuff, moved back in with my parents and decided I wanted to do this."

"This" means navigating her way alone through some of the world's trickiest corners, from the bullet-studded streets of Kabul to safe houses for rape victims in Kinshasa, often with little more than a scrap of paper and some scribbled notes as her guide.

Sharma has no set criteria for her heroes, whom she finds by using internet search engines and then relying on local contacts to determine the area's most pressing issues.

"What makes a hero, anyway? Is it that you're helping 1,000 people or two people?" she asks. "If you help the life of one single person but in a really meaningful way, I think you're a hero."

Sharma's latest find – number "70-something," she says – is 50-year-old social worker Maria do Socorro Melo Brandão, a favela-born but university-educated psychiatrist who now runs City of God's Seed of Life Association.

The community group works with local job-seekers and offers extra-curriculum activities to children and teens.

As Brandão describes her work providing counselling to slum residents, Sharma underlines the effect just one individual can have on the rest of the world. "All it takes is that one person who takes it upon themselves to put all of the pieces of the puzzle together, to inspire, to bring people together, that one person who doesn't give up," she says.

"Sometimes it's just about deconstructing the way people think. One amazing idea can disrupt the thinking of an entire community or country."

Determined to use "social media for social good", Sharma is raising money and awareness for the heroes she finds, using her journalistic background to blog, tweet and publish articles about her experiences.

Donors have been impressed: while she has paid for her trip primarily through personal savings, Indian travel site MakeMyTrip has funded all her flights — its chief marketing officer, Mohit Gupta, says he was inspired by Sharma's drive to "learn and imbibe the best the world has to offer".

Sharma admits that travelling solo has proven difficult at times – "I've been attacked, molested, robbed and duped," she says – but such experiences have only strengthened her resolve.

"Everywhere I travel, I do so through the eyes of a woman, and in most situations I feel violated or wronged, or unhappy or disconcerted, by what I see around me," she says.

"I now know I want to work in a women's rights organisation, with and for radical feminists, the radical [female heroes] in society who are clawing every day to create a new normal."

By the end of her two-year odyssey, Sharma will have seen the Northern Lights, churches of Lalibela, Ethiopia, and the pyramids of Egypt, crossed 45 countries over six continents, and found well over 100 heroes.

But only one thing will stand out, she says. "After time, every church starts looking the same. What I will remember most about this trip is the people — the undiluted love, welcoming and hospitality that I've experienced everywhere I've gone.

"It's a reminder of how lucky I am, how fortunate and privileged to be here and now and having this experience. To be able to bear witness. I could do this for the rest of my life."

Six of the best



Sonja Kruse The 32-year-old "Ubuntu Girl" spent a year travelling through her native South Africa with nothing but a backpack, camera and 100 rand (£7.75) to prove that ubuntu — an African concept meaning ''I am only because you are'' — is alive and well. She is writing a book about her experiences. www.theubuntugirl.co.za

Yamam Nabeel Iraqi-born, London-based Nabeel started FC Unity to bring together people from different social, religious and ethnic backgrounds through football, and teach them to work as a team. Since its founding in 2006, the charity has created football-based education and development programmes in Iraq, Sudan, England and Ghana. www.fcunity.com

Mahfuza Folad From an office above a Kabul cookie shop, Folad serves as executive director of Justice for All Organisation, which offers pro-bono advice and representation to Afghan women and lobbies for women's and children's rights. Folad is also a judge in the Kabul primary court. www.jfao.org

Dr Jo and Lyn Lusi The husband and wife co-founded HEAL Africa, which provides medical and social care for women in Congo, where 400,000 rapes are reported every year. Their charity heads one of Congo's three full-service hospitals and provides community-based initiatives such as safe houses and remote clinics, microlending schemes and law-training programmes. www.healafrica.org

Felicite Rwemalika The founder of the Association of Kigali Women in Sports, Rwemalika started Rwanda's first women's sports federation in 2001 to give young Hutu and Tutsi girls a chance to find reconciliation in post-conflict Rwanda. Her organisation also promotes women's rights and teaches reproductive health and economic empowerment. www.akwos.com