The Hidden Toll of Inequality on our Brains

By Raquel Loga

While the conversation about mental health has gone mainstream in the last decade, brain health is still an under-discussed topic. But it’s rapidly becoming one of acute importance: in 2021, 43% of the world’s population—about 3.4 billion people—had a condition affecting their nervous system, leading to 11.1 million deaths. The rise in dementia rates, particularly in low- and middle-income countries, reflects a need to improve brain health at the international level. 

Unfortunately, many aspects of our health are deemed our own responsibility. Our health is about our individual choices or genetics, we think, we just need to meal prep, squeeze in gym time, and turn off our phones before bed. But what if our health, and especially our brain health, was directly linked to our external environment? Are there factors affecting our brain health that we, personally, have little control over?

The link between inequality and brain health

A recent study has revealed a direct link between structural inequality and brain health. The study conducted neuroimaging analysis across six countries in the Americas on healthy individuals, Alzheimer’s patients, and people with frontotemporal lobar degeneration. 

Using the GINI index, which measures socioeconomic disparities by country, the researchers found that increased levels of inequality are associated with decreased brain volume and impaired connectivity, which is common in people with dementia and is linked to the progression and severity of the disease. 

In addition, they found that people with Alzheimer’s in countries with higher levels of inequality suffered more severely from the disease than people in other, less unequal countries.  Even after adjusting for individual factors like age, sex, education, and cognitive ability, these findings remained significant. The implications are staggering: long-term societal inequality becomes biologically embedded in a population, and even a high income or good education won’t keep you immune from its effects.

External factors of neurological diseases

Despite these and other findings, most public policies today fail to address the root causes of brain health disparities. Many scientists and public health experts argue that the current individual responsibility approach is inadequate and counterproductive. Several societal components that strongly correlate with brain health—like education, healthcare, and environmental protection—are often unaddressed or underfunded in unequal societies.

A high level of education, for example, has been linked to reduced dementia risk and improved late-life cognitive function. In the same vein, healthcare policies that focus on early intervention and preventative care can help reduce the burden of neurological diseases on patients and their families.

Another area not often mentioned regarding brain health is pollution. Inequality frequently leads to poor urban design and increased pollution in urban and rural areas. Both the actual pollution and the stress of poorly designed and polluted areas were shown to contribute to the progression of neurodegenerative diseases. 

The results are clear: people who live in poor environments are more likely to suffer from brain diseases. And there’s data to back it up: for example, in the United States, Black people, who are more likely to live in polluted areas with underfunded schools, are twice as likely to suffer from a stroke or dementia as white people.

Of course, some people in severely unequal societies have access to quality education, preventative healthcare, and a healthy environment. However, just the fact of living in long-term collective inequality has far-reaching neurological consequences that can and will affect everyone in that society, regardless of their socioeconomic level. 

Why policy interventions are the solution

Developing public policies to reduce inequality and keep our brains healthy is important both morally and economically. Current philanthropic efforts aren’t enough to address such deep-rooted systemic issues. Instead, policymakers must integrate neuroscientific, economic, and social factors into their policies, and use their agendas to address the structural determinants of brain health.

A variety of specific policies can address societal inequalities and promote brain health, including:

• Free or subsidized early childhood education

• Universal healthcare

• Strict air and water quality standards

• Funding for parks and pedestrian-friendly zones in all communities

• Paid family leave

• Funding for neuroscience research and brain health initiatives

• Progressive taxation

Undoubtedly, we won’t eradicate neurodegenerative diseases if all individuals are guaranteed education, preventative health care, green spaces, and sustainable urban planning. Still, strong public policies to reduce inequality will almost certainly make for overall healthier brains, and reduce the burden of these ailments on society. 

Healthy brains also provide long-term monetary benefits. Implemented policies should also promote positive cognitive skills including creativity, social adaptability, innovation, and entrepreneurship. As our economy continues to become more knowledge based, having strong brains becomes more critical to economic success. Happy brains create nations whose workforces are fit to tackle the problems we’re likely to face in the future.

The bottom line

On every level, more equal societies are healthier ones. Not only do they have lower rates of neurological diseases, but they have better rates of overall well-being, are more productive, and have lower healthcare costs. But philanthropic organizations alone, no matter how well-intentioned or -funded they are, will not get us there. 

While brain health is not our individual responsibility, there are steps we can take to push for policy change in our communities. By advocating for these policies in our local and national communities, seeking out and connecting with diverse and supportive environments that foster brain health, and engaging in lifelong learning, we can help foster and develop a future where everyone can thrive.

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