5.3: Why Health Is Unequal

A Toolkit for Explaining the Gap

Suppose two people develop the same illness.

One has paid sick leave, reliable transportation, insurance, nearby specialists, a pharmacy stocked with medication, a stable home, family support, and enough savings to absorb a month without working.

The other has none of those things.

Same diagnosis.

Very different odds.

At this point, blaming the microorganism feels a little inadequate.

Global health inequality is difficult to explain because there is rarely a single cause. Biology matters. Behavior matters. Health systems matter. Poverty matters. Political decisions matter. History matters. Race, gender, class, geography, disability, migration status, and environmental conditions may matter too, and often interact.

So we need a toolkit.

Not one theory that magically explains everything.

Several.

The social determinants of health framework directs us first toward the conditions of everyday life: housing, education, employment, food, transportation, social protection, environmental exposure, and access to health services. But the framework becomes most powerful when we keep going. Solar and Irwin (2010) emphasize that these everyday circumstances are shaped by deeper structural forces including governance, economic policy, labor markets, social policy, political institutions, and systems of stratification.

Otherwise, “social determinants” can become a fancy checklist. Housing , education, and income all matter. Fine, but why are those things distributed unevenly?

Michael Marmot's work on the social gradient in health demonstrates that health outcomes often improve step by step as socioeconomic position rises rather than dividing simply into “poor people” and “everyone else” (Marmot, 2005). That tells us something important: society itself may be organizing exposure, security, autonomy, and resources along a gradient.

A second tool, fundamental cause theory, helps explain why health inequality persists even as medicine improves. Bruce Link and Jo Phelan (1995) argued that socioeconomic position operates as a fundamental cause because it provides access to flexible resources (money, knowledge, power, prestige, and useful social connections) that people can deploy to avoid risks or reduce the consequences of disease.

The disease changes.

The advantage survives.

Research subsequently found evidence for a key implication of the theory: socioeconomic inequalities can be especially pronounced for illnesses where prevention and treatment are more available because resources help people capture those benefits (Phelan et al., 2004; Phelan et al., 2010). Imagine medicine discovers a new exit from a burning building. Excellent news. But some people are standing beside the door. Others are five floors away. Some received a map. Some have transportation. Some know the architect. Some own the building. The existence of an exit does not mean everyone reaches it equally. This helps explain a strange paradox: medical progress can improve population health while initially widening inequality. Screening becomes available, but those with better health coverage obtain it first. New health information appears, but those with more education and flexible employment are better positioned to act on it. A dangerous environmental exposure becomes known, but wealthier families can relocate more easily. Every new solution can become another inequality until access catches up.

Socioeconomic resources, however, do not explain every pattern. That is where intersectionality becomes useful. Kimberlé Crenshaw (1989) developed intersectionality to demonstrate how antidiscrimination frameworks could fail Black women when race and gender were treated as entirely separate categories. Public-health scholars subsequently applied intersectional analysis to health, asking how racism, sexism, class inequality, ableism, migration status, and other systems can overlap and produce distinctive health experiences (Bowleg, 2012; Bauer, 2014).

The key insight is not simply that people possess multiple identities. It is that systems of power interact. A migrant woman is not occasionally a migrant and occasionally a woman. A disabled Indigenous person does not encounter disability on Monday and colonialism on Tuesday. Categories do not live one at a time. Suppose national data suggest broadly similar health-service access for women and men. What happens when we disaggregate by race, income, disability, rural residence, or migration status? A reassuring national average may conceal severe inequality within particular populations. Intersectionality helps us see people who disappear inside averages.

Structural violence then pushes the analysis deeper into history and political economy. Farmer (2004) used this concept to explain how social arrangements systematically expose some groups to greater suffering while restricting access to resources that could protect them. His work on HIV/AIDS and tuberculosis in Haiti traced contemporary illness through colonialism, slavery, racism, poverty, political instability, and unequal medical access. The patient is not outside history. History is inside the patient. Structural violence does not require a secret group deliberately deciding who should suffer. A housing policy can concentrate populations in hazardous environments. A labor market can push people with few alternatives into dangerous work. A patent system can increase medicine costs. Debt can constrain health spending. Immigration policy can discourage people from seeking care. No single person needs to intend the final outcome. The system can still produce one. The political economy of health adds another essential question:

Where does the money come from?

Health systems need financing. Pharmaceuticals are developed inside markets. Health workers move toward jobs with better wages and working conditions. Hospitals compete for resources. Donors emphasize certain diseases. International financial institutions influence economic policy. Patents shape who can produce some medicines and what those medicines cost. Markets have generated extraordinary health innovation. They also answer one question especially well: What can be sold profitably? That is not always identical to: What would reduce the most human suffering?

Trouiller and colleagues (2002), for example, documented the severe underdevelopment of medicines for diseases disproportionately affecting populations with little purchasing power. This is one reason the term neglected diseases is so revealing: need and commercial demand are not the same thing. Research on structural adjustment has likewise examined how fiscal austerity, user fees, public-sector contraction, and constrained social spending can affect health systems, although outcomes vary substantially across countries and policies (Kentikelenis et al., 2017). A health budget is therefore not merely an accounting exercise. It represents choices. Who gets taxed? What gets funded? What gets privatized? Who absorbs the risk?

Finally, epidemiologist Nancy Krieger's ecosocial theory helps explain how all of these systems enter bodies. Her concept of embodiment describes how people biologically incorporate the material and social environments in which they live (Krieger, 2001). Air pollution becomes lung tissue. Chronic stress becomes hormonal activity. Dangerous work becomes injury. Food insecurity becomes nutritional deficiency. Extreme heat becomes cardiovascular strain. Political economy becomes biology. The body, in other words, keeps receipts. So which theory wins?

None.

Consider severe asthma in a low-income neighborhood. Social-determinants analysis asks about housing, pollution, access to care, employment, transportation, and income. Fundamental cause theory asks why households with greater resources can more easily avoid exposure or secure specialists. Intersectionality asks whether the burden differs according to race, class, gender, migration status, or disability. Structural violence asks which historical and political processes concentrated particular populations in hazardous environments. Political economy asks who profits from the housing or industry involved and whose interests shape regulation. Ecosocial theory asks how repeated pollution and stress become biologically embodied. Same child. Same asthma. Different analytical floors of the same building.

This is why we should beware the lifestyle trap. Smoking, exercise, diet, medication adherence, sleep, and other individual behaviors matter. But who can afford healthy food? Who has a safe place to exercise? Who works a schedule that permits adequate sleep? Who can purchase medication every month? Who is exposed to aggressive marketing of unhealthy products? Who lives next to the refinery? Link and Phelan's (1995) formulation remains useful: we have to ask what places people at risk of risks. That does not erase individual responsibility. It puts individual behavior inside the real world. When you encounter a health disparity, therefore, resist the urge to stop at the first plausible explanation. Ask who became sick, who was exposed, who had protection, who possessed resources, who made the rules, what history produced those rules, and who has the power to change them. That is the Global Studies move.

We now have several ways to explain unequal health outcomes. But explanation produces another question. If governments, markets, international organizations, pharmaceutical companies, foundations, NGOs, scientists, and communities all influence health...who is actually in charge?

Spoiler:

There is no Global Ministry of Health.

Which means things are about to get messy.