Aluminum Foil: Convenient In The Kitchen, But Is It Safe?

Authored by Sheramy Tsai via The Epoch Times (emphasis ours),

Aluminum foil, a kitchen staple used by millions for baking, grilling, and storing food, is now at the center of a growing debate. Concerns about aluminum safety have led experts to question whether this common household item may pose hidden health risks.

As studies reveal the potential for aluminum to leach into food during cooking—especially when acidic or salty ingredients are involved—scientists are examining whether cooking with aluminum foil contributes to the body’s overall aluminum burden. With aluminum present in many everyday products, understanding its cumulative impact on health is becoming increasingly important, say some.

Aluminum Foil: A Kitchen Essential

More than 93 percent of U.S. households use aluminum foil. Its durability and malleability make it a versatile tool, easily molded and shaped for various tasks.

Often referred to as tin foil, aluminum foil is a go-to choice for various cooking tasks. Whether roasting vegetables to a caramelized finish or grilling meats to a crisp, aluminum foil helps achieve the desired texture and finish. Foil “conducts heat evenly and keeps it consistent, making cleanup easier by keeping baking sheets clean,” Abbie Gellman, registered dietitian and chef, told The Epoch Times.

Aluminum foil is also used in packaging and catering, providing a reliable barrier against light, air, and harmful microbes that could lead to food spoilage. “For years, aluminum foil has been a reliable and trusted way of storing and cooking food,” a spokesperson from Reynolds Consumer Products, the maker of Reynolds Wrap, wrote in an email to The Epoch Times.

Latest Research on Cooking With Aluminum Foil

Studies show that aluminum foil is a major source of aluminum exposure and can contribute to aluminum buildup in our bodies, Christopher Exley, a chemist with more than 35 years of experience studying aluminum exposure, told The Epoch Times. “Leaching of aluminum into cooked food occurs wherever there is water, essentially juices from the food,” he added.

The amount of aluminum released depends on acidity, salt content, cooking temperature, and exposure time.

A 2020 study found that when acidic ingredients like lemon juice or salt are used, aluminum levels in fish and chicken can spike, reaching as high as 42 milligrams per kilogram (mg/kg). Acidic or salty foods, particularly when cooked at high temperatures or for extended periods, are more likely to absorb aluminum. Regular consumption of such foods could push aluminum intake beyond the safe weekly limit set by authorities, according to the authors.

“The phenomenon of aluminum leaching from aluminum foil to the food occurs and should arouse attention and concern,” the authors wrote, recommending that aluminum foil be avoided for baking to minimize health risks.

A Food Science & Nutrition study showed that marinated foods like fish and duck could have aluminum levels spike to as much as 117 mg/kg. The researchers stated that their study “also confirmed that consumers are not enough informed about [the] hazardous side of aluminum foil usage.”

Baking in aluminum foil can also increase aluminum content in food. Research published in 2018 found that cakes baked in aluminum foil had significantly higher aluminum levels, which increased further with prolonged storage.

While these findings are concerning, not all studies paint a grim picture. A 2023 study funded by the European Aluminum Foil Association found that any increase in aluminum levels from a high-exposure diet was small and reversible. The additional aluminum was excreted or reduced to baseline levels within 10 days after ceasing exposure, assuming no other significant aluminum sources were consumed during that period. Still, experts recommend caution, particularly when using aluminum foil with acidic or salty foods, to minimize unnecessary aluminum intake.

In response to these concerns, the International Aluminum Institute told The Epoch Times in an email that most studies show only minimal amounts of aluminum from cookware and foil entering food, with the majority being eliminated by the body. “Very little of the aluminum that we ingest from foods and food contact materials is absorbed by the body,” according to the Institute.

Using aluminum pans, bowls, and foils with acidic or salty foods can increase aluminum concentrations in the food, but exact amounts are hard to pin down because it’s challenging to determine the exact source of aluminum in food, according to the European Food Safety Authority (EFSA). This is due to the complexity of dietary studies, which may not be able to determine whether the aluminum comes from additives, natural presence, or leaching during cooking.

Aluminum Everywhere

Aluminum foil isn’t the only source of our exposure. Aluminum is one of the most abundant metals in the Earth’s crust, accounting for about 8 percent of its total mass. It permeates nearly every aspect of daily life, appearing not just in kitchens but also in food, water, cookware, personal care products, medications, vaccines, and even the air we breathe.

Many everyday foods, such as tea, leafy vegetables, and certain grains, contain trace amounts of aluminum. The World Health Organization (WHO) estimates that the average American adult consumes between 7.1 and 8.2 milligrams of aluminum daily through food and water, which is between 50 and 60 milligrams a week.

A safe weekly intake of aluminum is 1 milligram per kilogram of body weight, according to current WHO and EFSA guidelines. For an average adult weighing 154 pounds, this translates to a maximum of 70 milligrams of aluminum per week to minimize any potential long-term health risks.

While aluminum is prevalent in our environment, it doesn’t have a necessary role in our bodies, unlike many other metals, including zinc, copper, and iron.

The Agency for Toxic Substances and Disease Registry, part of the U.S. Department of Health and Human Services, states that the human body can usually handle small amounts of aluminum, primarily excreting it through the kidneys. While high levels of exposure can be harmful, particularly for those with kidney issues, typical dietary and environmental exposures are generally not considered a concern for most people.

However, many people are unaware of the extent of their daily aluminum exposure, Exley said. “Much as a bee forages for nectar apparently oblivious to its additional bounty of aluminum, we are also blind to the myriad ways that everyday life exposes us to aluminum,” he wrote in the journal, Environmental Science: Processes & Impacts.

Cumulative Exposure

The human body is generally efficient at preventing aluminum absorption through the gastrointestinal tract. However, accurately measuring aluminum absorption and excretion is a challenge, making it difficult to establish safe exposure levels. This adds to the uncertainty surrounding the effects of aluminum, Exley said.

Studies have shown that only about 0.1 to 0.4 percent of ingested aluminum is actually absorbed. But, according to Exley, the amount of ingested aluminum that enters the bloodstream may be up to 30 percent. Whatever amount is absorbed at any given time contributes to what researchers refer to as the “body burden” of aluminum, which can accumulate in tissues like the brain.

“Aluminum may persist for a very long time in various organs and tissues before it is excreted in the urine,” according to the EFSA. They also highlight that humans tend to retain aluminum longer than rodents.

“It’s not just aluminum foil we need to be concerned about—it’s the cumulative exposure to aluminum in our daily lives,” Exley said. “I’m not advocating complete avoidance, but I recommend using it judiciously.”

Potential Neurological Effects

One of the most discussed aspects of aluminum exposure is its potential impact on the brain. “Although we know for sure that aluminum accumulates in the brain, it is not fully understood how it reaches it,” according to a 2023 study published in the International Journal of Molecular Sciences.

“It is widely accepted that Al [aluminum] is a recognized neurotoxin,” states another study in the Journal of Research in Medical Sciences

Aluminum can cross the blood-brain barrier, potentially leading to neurotoxic effects. Studies have associated high levels of aluminum with neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis.

In Alzheimer’s disease, aluminum has been found in the brains of patients at higher concentrations than in those without the disease. Some studies suggest that aluminum may contribute to the formation of amyloid plaques and neurofibrillary tangles—hallmarks of Alzheimer’s pathology.

The Alzheimer’s Association dismisses the idea that aluminum cookware or containers cause Alzheimer’s as a myth, stating, “Studies have failed to confirm any role for aluminum in causing Alzheimer’s. Almost all scientists today focus on other areas of research, and most experts believe aluminum does not pose any threat.”

Similarly, the Centers for Disease Control and Prevention acknowledges uncertainty, noting that while some studies link high aluminum exposure to Alzheimer’s, others do not. “We do not know for certain that aluminum causes Alzheimer’s disease,” they said.

Research has also linked occupational exposure to aluminum, such as in mining or welding, to an increased risk of Parkinson’s disease, with aluminum potentially exacerbating the formation of toxic protein aggregates in the brain.

Other Health Impacts

A 2022 study published in Emergency Medicine International highlights other potential health risks associated with significant or prolonged exposure to aluminum. The findings suggest that while everyday contact with this metal is unlikely to cause serious harm, high levels of exposure can contribute to a range of health issues.

Neurological damage: Aluminum exposure can lead to memory loss, tremors, diminished coordination, seizures, coma, and potentially death.
Bone disorders: Accumulation of aluminum in bones can cause osteomalacia (softening of bones), osteoporosis, non-healing fractures, and other musculoskeletal issues.
Kidney and liver damage: Aluminum poisoning can lead to kidney damage, changes in urea and creatinine levels, and liver conditions such as fatty liver and Type 2 diabetes.
Respiratory issues: Prolonged exposure to aluminum dust can cause respiratory problems, including asthma, chronic bronchitis, chronic obstructive pulmonary disease, and possibly lung cancer.
Blood disorders: Aluminum exposure can alter red blood cells, leading to anemia characterized by abnormal cell shapes and sizes.
Oxidative stress: Aluminum can increase oxidative stress in the body, leading to cellular damage, particularly in the brain, liver, and kidneys.
Enzyme inhibition: Exposure to aluminum may disrupt enzyme activities, protein synthesis, and DNA repair, contributing to various health issues.

The study suggests that aluminum exposure may not directly cause these conditions, but it can be a contributing factor.

Reducing Aluminum Exposure

There are simple and practical steps you can take to minimize contact with aluminum in your daily life.

Alternatives to aluminum:

Cooking food: Consider switching to glass or ceramic cookware instead of aluminum, and avoid using aluminum foil with acidic or salty foods.
Storing food: Use glass containers to keep your food fresh and safe from aluminum.
Baking: Opt for glass, ceramic, stainless steel, silicone, or unbleached parchment paper instead of aluminum pans.
Grilling: Cook directly on the grill, use a grill basket, or try cedar grilling papers as a substitute for aluminum foil.

For those concerned about their aluminum levels, tests on blood, urine, or hair can provide some insight. However, it’s important to note that these tests mostly reflect recent exposure and may not fully capture long-term accumulation, as much of the body’s aluminum is stored in tissues and bones.

Although the body can naturally excrete aluminum, it’s important to minimize unnecessary exposure in vulnerable groups like children, older adults, and people with kidney issues.

As new findings emerge, the debate over aluminum foil’s safety remains unresolved. While it offers undeniable convenience, understanding and managing the potential risks is crucial for making informed choices in the kitchen.