This article originally appeared on Economist.com.

When historians write about the first quarter of the 21st century, they may sum it up this way: 20 years of unprecedented progress followed by five years of stagnation.

This applies to almost every issue the Bill & Melinda Gates Foundation works on, from poverty reduction to primary school enrollment. But nowhere is the contrast more stark and tragic than in health.

Between 2000 and 2020, the world witnessed a global health boom. Child mortality decreased by 50%. In 2000, more than 10 million children died each year, but now the number is less than 5 million. The incidence of the world’s deadliest infectious diseases has also halved. Best of all, progress occurred in regions where the disease burden was highest. The greatest improvements were seen in sub-Saharan Africa and South Asia.

Then Covid-19 hit and progress came to a screeching halt.

Today the world faces more challenges than at any point in my adult life: inflation, debt, new wars. It is also grappling with the worst crisis in child health: malnutrition. Unfortunately, aid is not keeping pace with these needs, especially in the places that need it most.

When a child dies, half of the cases are due to malnutrition. Climate change is making the situation worse. According to new data from the Institute for Health Metrics and Evaluation, between 2024 and 2050, approximately 40 million additional children will be stunted and 28 million will be stunted as a result of climate change. These conditions, the most severe forms of malnutrition, prevent children from developing to their full potential mentally and physically.

The health and economic consequences are disastrous. A child who experiences severe malnutrition before the age of three will complete schooling in five years less than well-nourished children, and research shows that people who went hungry as children earn 10% less over the course of their lives and have 33% less less chance of escaping poverty.

An extended version of this article can be found in the 2024 Goalkeeping Report.

We must invest in global health to protect children from the worst effects of hunger, mitigate the effects of climate change and boost economic growth. Looking back can inspire you to rekindle progress.

The global health boom had many causes. A new generation of political leaders embraced humanitarianism. Hundreds of thousands of health care workers have spread across the world, bringing the latest medicines to places that doctors rarely visit. However, an often overlooked factor was a small – but crucial – increase in funding.

Beginning in 2000, the world’s richest countries began to steadily increase their funding to supplement those for low-income countries as they increased their own investments in health care. Over the first 20 years of the century, OECD countries steadily increased foreign aid from an average of 0.22% of their gross national income to 0.33%, with the most generous countries contributing about 1%. In 2020, low-income countries received an average of $10.47 per person. It doesn’t seem like much, but that $10.47 made a remarkable difference. This fueled the work of organizations such as Gavi, the Vaccine Alliance and the Global Fund to Fight AIDS, Tuberculosis and Malaria, which ensured that poorer countries had access to life-saving vaccines, drugs and other medical breakthroughs.

The impact of this generosity was stunning. However, the work is unfinished. Today, over half of all child deaths still occur in sub-Saharan Africa. Since 2010, the share of poor people in the region worldwide has increased by more than 20 points, to almost 60%. Yet over the same period, the share of total foreign aid going to Africa fell from almost 40% to just 25%, the lowest percentage in 20 years. Fewer resources mean more children will die from preventable causes.

The global health boom is over. But for how long? This is a question I have been struggling with for five years. Will we remember this period as the end of a golden era? Or maybe it’s just a short break before the next boom begins?

I’m still optimistic. I think we can give global health a second life – even in a world where competing challenges require governments to stretch their budgets. To do this, we will need a two-pronged approach.

First, the world must re-engage in the work that fueled progress in the early 21st century, especially investment in key vaccines and medicines. They continue to save millions of lives every year.

We also need to look to the future. The R&D portfolio is full of powerful and surprisingly profitable breakthroughs. We must use them to fight the most common health crises. And it starts with good nutrition.

One of the few failures of the global health boom has been our failure to understand the importance of nutrition. However, over the last 15 years, doctors have begun to discover how the stomach affects every aspect of human health. If we solve the problem of malnutrition, we will make it easier to solve many other problems. We solve extreme poverty. Vaccines are more effective. And deadly diseases like malaria and pneumonia become much less deadly.

This knowledge is now being turned into surprisingly profitable innovations such as super-fortified broth and more effective prenatal vitamins. The impact of scaling up these innovations would be incredible. In Nigeria, modeling shows that fortifying bouillon cubes would not only prevent anemia; it would also avoid more than 11,000 deaths from birth defects of the central nervous system called neural tube defects. And if low- and middle-income countries adopted the most complete form of vitamins for pregnant women, called multinutrient micronutrient supplements, almost half a million lives could be saved by 2040.

The initial global health boom is over. – But for how long? this is an issue that humanity still has control over. I believe we can start a second global health boom by providing children with the nutrients they need to thrive.