Poor health is one of the major obstacles to development in the world’s poorest countries. Entrepreneurial solutions can help, but they need to be simple, culturally sensitive and scalable to make a dent. Here are three original ideas with the potential to do just that.

Life Saving Dot – providing iodine to women in rural India

Iodine deficiency is the world’s most prevalent cause of brain damage, along with a host of other health complications. In India, the problem is particularly acute because of low levels of iodine in the soil. Iodine-fortified salt mitigates the risk, yet the cost means an estimated 350 million Indians do not consume it.

Life Saving Dot, the brainchild of advertising company Grey Group, aims to provide women in rural India with the daily dose required by impregnating self-adhesive bindis with an iodine solution. For millennia, the bindi – the Hindu symbol of the chakra – has been used across India. The treated bindis act as transdermal patches, providing women with the 150 to 220 micrograms of iodine they require daily.

The beauty of the idea is that it fits into an established cultural tradition, says Ali Shabaz, chief creative officer of Grey Group Singapore. “It’s hard to get [rural women] to make massive behavioural changes”, he says. But here “all they have to do is wear the same bindi that they wear every day”.

Grey Group is working with Talwar Bindi, one of India’s largest bindi producers, to distribute the product for free in a small number of pilot areas. Grey Group, which developed the idea through its philanthropic arm, is in discussion with a number of Indian companies interested in funding wider distribution as part of their mandatory CSR investment requirements. Shabaz’s hope is that the solution will be rolled out nationwide as part of a publicly-funded health programme.

Lucky Iron Fish – tackling iron deficiency in Cambodia

Iron deficiency is the most common nutritional deficiency in the world and a major cause of anaemia, which results in everything from fatigue and dizziness to impaired immune function.

Following fieldwork in Cambodia, Canadian epidemiologist Chris Charles discovered that placing a small piece of iron into an aluminium pot while cooking could release sufficient iron to provide up to 75% of people’s recommended daily intake. The simple solution provides an alternative to iron-rich foods and supplements, which are often not available in poor areas or too expensive.

“No one wanted to cook with this ugly piece of iron, though,” says Gavin Armstrong, chief executive of Lucky Iron Fish, a small healthcare company. By shaping the iron like a fish it became linked to traditional associations of luck and prosperity.

Proving the health benefits is key to encouraging uptake, says Armstrong. Lucky Iron Fish is currently in clinical trials but initial results show a 50% drop in iron deficiency after a year of cooking with the iron fish. Although the research also brings up challenges around the long term effectiveness of the fish and difficulties in getting people to change their cooking behaviour.

To help scale up the solution, the organisation switched from charity status to become a social enterprise in 2012. Lucky Iron Fish’s primary clients are development agencies operating in Cambodia. Bought in bulk, the iron fish cost between $5-$8 (£3.20-£5.13) and last for five years, a major reduction on the $30 per person per year that health charities typically spend providing iron supplements.

In 2012-2013, the company raised C$1.3m (£662,000) in equity funding, thanks in large part to a matched grant of C$500,000 (£255,000) from the government-backed healthcare funder Grand Challenges Canada. Armstrong plans a second round of financing within the next year to fund an expansion into other south-east Asian markets.

Kidogo – providing childcare in Kenya’s slums

Last week 12-month-old Lenslot Aoko was dropped off as usual at Kidogo’s day-care centre in Nairobi’s Kibera slum, the largest informal settlement in Africa. The staff noticed he had feverish symptoms and took him to hospital, where he was diagnosed with pneumonia, one of the biggest killers of children under five-years-old in the region.

“A middle or upper income child with these symptoms would be admitted to intensive care right away, no question,” says Sabrina Premji, co-founder of the social enterprise Kidogo, which provides early childhood care and education in East Africa’s urban slums for around 70 Kenyan shillings (45p) a day. “Lenslot’s mother said if her child was anywhere else, they would not have noticed that he was on his final breaths and he would have died.”

Kidogo’s low cost childcare centres provide nutritious meals and basic health interventions such as vaccinations, on top of a play-based curriculum. In addition, they provide training and materials to local baby-care centres through a micro-franchising model. This model expands Kidogo’s reach, while its fee-for-service approach means it’s not dependent on donor aid. Kidogo’s second centre opened in Kangemi, another slum in Nairobi, in January and broke even within six weeks.

“We wanted to design a model that could be financially sustainable so that when donor priorities change or early childhood is no longer the sexy thing to fund, our programmes could continue to flourish,” explains Premji.

Local ownership is vital to the acceptance and success of the childcare centres. From the outset, Premji and her co-founder were anxious that the social enterprise wasn’t seen as a “mzungu” (white person) project. Hiring Kenyan staff, involving parents in decision-making and running open days for the community have helped avoid such an eventuality.

The Aga Khan University is currently carrying out a rigorous case-control research study of Kidogo’s model, with improvements in physical health one of the study’s core outcome measures. Around 2.5 million children in east Africa’s slums have no access to early childhood care, Premji states. “Without a basic education and with significant health challenges, these children find themselves locked in a cycle of poverty that is near impossible to escape.”

• This article was amended on 3 July 2015: Ali Shabaz is chief creative office of Grey Group Singapore not chief executive