Exposure to Heavy Metals Linked to Dementia Risk

Toxic metals like lead, cadmium, and manganese are widespread in our environment and are associated with impaired cognitive function and cognitive decline.

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As the prevalence of Alzheimer’s disease and dementia continues to rise, a growing body of research is sounding the alarm on a possible culprit: heavy metal exposure.

From the medications we take to the water we drink and potentially even the air we breathe, our environment contains metals such as lead, cadmium, and aluminum. These metals can increase the risk of cognitive decline and neurological conditions.

Environmental Factors Fueling Cognitive Decline

Nearly 7 million Americans live with Alzheimer’s disease, and this number is projected to almost double by 2050, according to the Alzheimer’s Association.

Studies on humans consistently demonstrate that exposure to lead, cadmium, and manganese is associated with impaired cognitive function and cognitive decline.

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Cadmium, in particular, has been increasingly released into the environment through industrial activities such as coal mining and the use of phosphate fertilizers on crops.

Aluminum, another metal linked to an increased risk of dementia, is being considered as part of potential geoengineering methods to mitigate climate change through the injection of aerosols into the lower stratosphere. This could lead to an increased risk of exposure to aluminum compounds for humans and ecosystems.

The legalization of marijuana in a growing number of U.S. states may also exacerbate the problem of toxic metal exposure. A 2023 study found that cannabis users had significantly higher levels of lead and cadmium in their blood and urine than did nonusers. Researchers discovered that the cadmium levels in cannabis users were, on average, 22 percent higher in blood and 18 percent higher in urine. Lead levels were elevated by 27 percent in blood and 21 percent in urine among these users.

According to the Environmental Protection Agency, there is no safe level of lead exposure.

Trace Metals That Mitigate Dementia Risk

Although some metals can adversely affect neurological health, many essential trace metals could potentially reduce the risk of Alzheimer’s disease and other forms of dementia. These trace metals, or minerals, play a crucial role in maintaining brain health and mitigating the risk of neurodegenerative diseases when not consumed in excess.

• Magnesium is neuroprotective and reduces oxidative stress and inflammation
• Zinc is essential for immune functions and brain communication
• Copper reduces oxidative stress and inflammation
• Selenium improves cognition in mild cognitive impairment

Food sources rich in these trace metals include:

• Various nuts such as almonds, walnuts, and pecans
• Seeds such as chia, flax, and sunflower
• Legumes such as lentils, chickpeas, and black beans
• Whole grains such as whole oats, quinoa, and barley

Although these trace metals may have a neuroprotective effect, they are not a substitute for established treatments for Alzheimer’s disease and dementia. A comprehensive treatment plan that includes lifestyle changes, medications, and cognitive training is still necessary to manage these conditions effectively.

Exposure to Heavy Metals in Daily Life

Prolonged exposure to low levels of aluminum can lead to changes associated with brain aging and neurodegeneration, a scientific review published in Toxicology showed. The use of antacids made with aluminum hydroxide is one of the main sources of aluminum exposure in humans.

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There is no known way to reverse the damage caused by aluminum exposure, Dr. Charles M. Janssens, an internal medicine specialist in Cincinnati, told The Epoch Times. “The brain is demonstrated to have some plasticity and regenerative ability,” he said. “But the best course of action is to remove the source causing the insult.”

The way we’re exposed to these metals varies. “With lead and arsenic, it is primarily through dietary sources, and for other metals, it is more due to occupational exposure,” Dr. Janssens said.

Certain foods and spices, including imported candy, coriander, turmeric, and chili powder, have also been found to contain lead.

Although aluminum has been associated with impaired cognition, this doesn’t necessarily mean you need to throw out your aluminum cookware. These metals need to be in a certain state, such as gas or liquid, to be absorbed into our bodies and cause harm, Dr. Janssens said.