There’s a simple reason we have missed the critical importance of breast milk for lifelong health. “It’s because science has been completely focused on the diseases of rich, middle-aged white men” says the UC Davis professor and researcher Dr Bruce German. Heart disease, high cholesterol, high blood pressure – these are the ailments that science has been focused on treating since the 1950s.

Around that same time, infant formula became readily available and doctors and hospitals began recommending it widely. It was seen as an advance that went largely unquestioned in mainstream culture and society. The idea that formula was comparable to breast milk persisted for decades, and it wasn’t until the 1980s that it came under intense public scrutiny when it was revealed that after aggressive marketing to women in poor countries, Nestlé infant formula was responsible for the deaths of 66,000 babies when formula was mixed with contaminated water.

Despite the scandal and the sheer immensity of the tragedy, formula marketing persisted and is now a $70bn industry controlled by just a handful of corporations.

The public was reminded of the power these companies wield when it was reported that Donald Trump’s UN delegation was threatening other countries with trade sanctions and the removal of military aid if they did not agree to water down the language of a breastfeeding resolution. The resolution urged governments to “protect, promote and support breastfeeding” as well as restrict the advertising of harmful food products, according to the New York Times report.

This stunned the international health community which has long been in agreement about the irrefutable benefits of breastfeeding. Well-established health benefits of breastfeeding for the baby include: decreased risk of asthma, childhood leukemia, childhood obesity, ear infections, eczema, diarrhea and vomiting, sudden infant death syndrome, and type 2 diabetes. The American Academy of Pediatrics recommends breastfeeding at least 12 months and until the child is two years of age, if possible. The World Health Organization recommends two years or more.

What else is lost when we ignore the overwhelming evidence for the health benefits of breastfeeding? First, the threat to women and babies in poor countries is still a major concern – 25,000 babies a year still die after drinking formula mixed with contaminated water, according to Mother Jones.

But there are some other crucial and less well-known factors that we are just beginning to understand about the vital role that breast milk plays in our long-term health.

With the discovery of the microbiota – the trillions of bacterial cells that live in and on us, and without which we could not survive – researchers are learning about the critical role breast milk plays in establishing a healthy microbiota. Breast milk, as well as the closeness to a mother’s body that breastfeeding allows, provides the transfer of important beneficial bacteria to the baby. Then, a mother’s milk provides a complex array of carbohydrates that the bacteria need to live and reproduce – something infant formula does not have.

A healthy infant microbiota educates the immune system, which protects the baby immediately from acute illness, but it also programs the immune system for life during this important developmental window. What researchers are beginning to understand is that the disruption to the natural processes of forming a protective microbiota through breastfeeding seems to have disastrous consequences leading to the development of autoimmune diseases and conditions, ranging from increased risk for allergies to certain cancers.

What’s more, when a baby is not breastfed, she is less likely to be accepting of the wide array of flavors found in natural, whole foods. Flavors in a mother’s diet come through in her breast milk, teaching the baby what to expect with solid foods. In contrast, formula’s flavor never changes. Researchers believe the baby could be less likely to eat a diverse and healthy whole foods diet later in life.

But we have completely ignored the importance of breast milk for decades, moving toward an industrialized way of feeding babies: infant formula. Infant formula – the first processed food – undermines the life-promoting benefits of mother’s milk and is a poor substitute for breast milk nutritionally. It also deprives babies of their ability to develop a healthy and robust microbiota, and may set them up for a preference for less healthy foods and greater risk for diet-related disease.

The United States alone has invested billions of dollars researching treatments for these diet-related diseases instead of focusing on prevention. In the words of the researcher, Dr German, we should be regarding the exchange between the mother-infant dyad as the foundation for lifelong health. He refers to breast milk as the Rosetta Stone for nutrition – it provides the blueprint for what human beings need not only to survive but to grow and thrive in sometimes harsh conditions.

He emphasizes how lactation is therefore the model for how to nourish humans completely, comprehensively, preventatively, and safely, as well as sustainably and deliciously.

Prevention is not something our healthcare system is well-known for. But the foundation for lifelong health begins with giving women the support they need to be able to breastfeed their babies. The Trump delegation’s latest tactic at the UN is turning the clock back on important policy advances and ignores the well-documented evidence in support of breast milk for optimal health.

And the great irony of all this is, that once we finally recognize the deep importance of breastfeeding for lifelong health, those seemingly intractable diseases of rich, middle-aged white men could disappear.

• Kristin Lawless is the author of Formerly Known as Food: How the Industrial Food System Is Changing Our Minds, Bodies, and Culture.