Absorption: How readily a food absorbs and holds on to aluminum
Soil: The aluminum content of the soil the food was grown in
Packaging: If the food has been packaged and stored in aluminum packaging
Additives: Whether the food has had certain additives added during processing
Aluminum is also ingested through medications that have a high aluminum content, like antacids.
Regardless, the aluminum content of food and medication isn't considered to be a problem, as only a tiny amount of the aluminum you ingest is actually absorbed.
The rest is passed in your feces. Furthermore, in healthy people, absorbed aluminum is later excreted in your urine (5, 6).
Generally, the small amount of aluminum you ingest daily is considered safe (2, 7, 8).
Summary: Aluminum is ingested through food, water and medication. However, most of the aluminum you ingest is passed in feces and urine and is not considered harmful.
Most of your aluminum intake comes from food.
However, studies show that aluminum foil, cooking utensils and containers can leach aluminum into your food (6, 9).
This means that cooking with aluminum foil may increase the aluminum content of your diet. The amount of aluminum that passes into your food when cooking with aluminum foil is affected by a number of things, such as (6, 9):
Temperature: Cooking at higher temperatures
Foods: Cooking with acidic foods, such as tomatoes, cabbage and rhubarb
Certain ingredients: Using salts and spices in your cooking
However, the amount that permeates your food when cooking can vary.
For example, one study found that cooking red meat in aluminum foil could increase its aluminum content by between 89% and 378% (10).
Such studies have caused concern that the regular use of aluminum foil in cooking could be harmful to your health (9). However, there is currently no strong evidence linking the use of aluminum foil with an increased risk of disease (11).
Summary: Cooking with aluminum foil can increase the amount of aluminum in your food. However, the amounts are very small and deemed safe by researchers.
The day-to-day exposure to aluminum that you have through your food and cooking is considered safe.
This is because healthy people can efficiently excrete the small amounts of aluminum the body absorbs (12).
Nevertheless, dietary aluminum has been suggested as a potential factor in the development of Alzheimer's disease.
Alzheimer's disease is a neurological condition caused by a loss of brain cells. People with the condition experience memory loss and a reduction in brain function (13).
The cause of Alzheimer's is unknown, but it is thought to be due to a combination of genetic and environmental factors, which can damage the brain over time (14).
High levels of aluminum have been found in the brains of people with Alzheimer's.
However, as there is no link between people with a high intake of aluminum due to medications, such as antacids, and Alzheimer's, it's unclear if dietary aluminum is truly a cause of the disease (6).
It is possible that exposure to very high levels of dietary aluminum may contribute to the development of brain diseases like Alzheimer's (15, 16, 17).
But the exact role aluminum plays in the development and progression of Alzheimer's, if any, is yet to be determined.
In addition to its potential role in brain disease, a handful of studies have suggested that dietary aluminum could be an environmental risk factor for inflammatory bowel disease (IBD) (18, 19).
Despite some test-tube and animal studies that allude to correlation, no studies have yet found a definitive link between aluminum intake and IBD (20, 21).
Summary: High levels of dietary aluminum have been suggested as a contributing factor to Alzheimer's disease and IBD. However, its role in these conditions remains unclear.
It's impossible to completely remove aluminum from your diet, but you can work to minimize it.
The World Health Organization (WHO) and Food and Drug Administration (FDA) have agreed that levels below 2 mg per 2.2 pounds (1 kg) body weight per week are unlikely to cause health problems (22).
The European Food Safety Authority uses a more conservative estimate of 1 mg per 2.2 pounds (1 kg) body weight per week (2).
However, it's assumed that most people consume much less than this (2, 7, 8) Here are some steps you can take to minimize unnecessary exposure to aluminum when cooking:
Avoid high-heat cooking: Cook your foods at lower temperatures when possible.
Use less aluminum foil: Reduce your use of aluminum foil for cooking, especially if cooking with acidic foods, like tomatoes or lemons.
Use non-aluminum utensils: Use non-aluminum utensils to cook your food, such as glass or porcelain dishes and utensils.
Avoid mixing aluminum foil and acidic foods: Avoid exposing aluminum foil or cookware to acidic food, such as tomato sauce or rhubarb (23).
Additionally, as commercially processed foods can be packaged in aluminum or contain food additives that contain it, they may have higher levels of aluminum than their homemade equivalents (3, 4).
Thus, eating mostly home-cooked foods and reducing your intake of commercially processed foods may help to reduce your aluminum intake (2, 3, 8).
Summary: Aluminum exposure can be reduced by decreasing your intake of highly processed foods and reducing your use of aluminum foil and aluminum cooking utensils.
Aluminum foil isn't considered dangerous, but it can increase the aluminum content of your diet by a small amount.
If you are concerned about the amount of aluminum in your diet, you may want to stop cooking with aluminum foil.
However, the amount of aluminum that foil contributes to your diet is likely insignificant.
As you are probably eating far below the amount of aluminum that is considered safe, removing aluminum foil from your cooking shouldn't be necessary.