Whether it is to grill or bake your food, wrap up leftovers in, or pack food for easy reheating in the oven, aluminum foil makes cooking convenient and mess-free in so many ways. But could this convenient kitchen tool be harming your health? While the Aluminum Association stands by their metal, saying that the scientific evidence reveals no harmful effects from normal exposure, there are other voices that caution against its use in cookware or even aluminum foil. Here’s a closer look to see how things stack up.
Aluminum Leaches Into Food From Foil: Temperature And Acidity Make A Difference
The main concern around aluminum foil is that the metal leaches into your food, raising its content in your body. As it turns out, the metal does, in fact, seep into the food when you cook in it. And factors like the acidity of the food and the temperature at which you’re cooking modulate how much of it enters your food.
One piece of research studied the change in levels of aluminum in food before and after it was cooked in aluminum foil. Researchers found that cooking food at high temperatures even for a short duration could cause more leaching. In their study, samples of meat and poultry baked at 250°C for just 20 minutes saw the concentration of the metal rise by between 153 and 378 percent. On the other hand, those baked at 150°C for 60 minutes went up by a lower amount – 76 to 115 percent.1
The acidity of the food you’re cooking also makes a difference. So if your food is highly acidic, it is likely to cause more of the metal to leach into the food.2 The study above showed that the pH value of the salt, spices, and food all impact the amount of aluminum that is leached into the food.3
How your body takes to this and whether or not it will harm you then depends on
- Your own overall health
- How much metal accumulation you can tolerate
- How high your levels are compared to the permissible limits (outlined by the World Health Organization (WHO))
Aluminum Intake Up To 2 Mg/Kg Body Weight Per Week Is Fine
Health authorities like the WHO say that aluminum content of food, water, and medication does not normally pose a risk to most people.4 And this includes the aluminum you may find in your food or drinking water, medicines, cosmetics, or even cookware.5
This is because when you consume aluminum through food or water, only a very small fraction of it is actually absorbed by your body while the rest is expelled in the form of urine and stool. As per estimates, you absorb anywhere from as little as 0.2 percent to 1.5 percent of all ingested aluminum.6 Which means foil on its own isn’t a problem.
Your body can also release small amounts of aluminum quite efficiently, so you won’t end up accumulating too much in your body from foil alone. According to the Joint FAO/WHO Expert Committee On Food Additives, it is safe to have about 2 mg/kg of your body weight every week.7 But no more than this.
Foil Use Isn’t Harmful, But Watch Out For Dangerous Cumulative Effect
Stay well within the safety limits of aluminum, whether it is from foil or food, and you should be okay. The trouble is when the cumulative effect of the metal from water, food, and conveniences like foil begin to push the levels of intake higher. The average daily dietary aluminum intake seems to be 6 to 14 mg per day among both teenagers and adults, coming from grains, dairy, beverages, desserts, and foods that have higher aluminum levels. Certain foods like cayenne pepper, tea, baking powder, processed cheese do contain more aluminum while other foods that have aluminum-containing additives. Having these in very high amounts may also cause you to inadvertently have too much of the metal.8
Neurotoxic Effects And Alzheimer’s Risk From Excessive Aluminum Intake
Aluminum is a known neurotoxin that can result in dementia as well as cognitive deficiency when the metal accumulates in the brain. It may also interfere with the normal function of your central nervous system.9 Aluminum exposure has also been listed by some researchers as a possible risk factor for dementia.10
Exposure to the metal has been linked to neurodegenerative diseases like Parkinson’s dementia and Alzheimer’s disease.11 Some reports show a correlation between areas with high aluminum content in water and a high incidence of Alzheimer’s.12 Researchers have gone so far as to strongly recommended immediate steps for reducing human exposure to aluminum – a metal they term “the single most aggravating and avoidable factor” contributing to risk of Alzheimer’s disease.13
Stunted Growth Rate Of Cells Due To Aluminum Exposure
Studies in cultured human brain cells demonstrated reduced growth of cells when the sample was exposed to 0.1 to 10 mg/l concentrations of aluminum. The higher the aluminum concentration the cells were exposed to, the more drastic the slowing of growth.14
Toxicity Risk For Those With Kidney Problems
If you have a kidney problem, the impaired function of your kidneys will mean your body is not able to rid itself of excess aluminum as efficiently as before. The result can be aluminum toxicity which is potentially fatal.15 In fact, the National Kidney Foundation actually has guidelines on aluminum exposure and suggest serum aluminum level tests annually for anyone with chronic kidney disease(stage 5). This needs to be done every 3 months if any aluminum-containing medications are being taken. Dialysis doesn’t help remove enough of the metal because it accumulates in body tissues and organs, bone, parathyroid glands, and the brain.16 Needless to say, exposure to aluminum leached from foil is best avoided if you have any kidney problems.
Possible Role In Inflammatory Bowel Disease
Your dietary intake of aluminum may also play a part in the risk of developing inflammatory bowel diseases (IBD). The metal was seen to increase intestinal inflammation in test animals with colitis.17 Researchers suggest that it may play a role in inducing inflammation in Crohn’s disease as well.18 That said, there are inadequate studies or research to firmly establish the cause and effect relationship so far. If you feel you may be at risk of these conditions, it may be better to steer clear of using too much foil or ingesting too much dietary aluminum.
Some People More At Risk Of Problems Linked To Aluminum Intake
Researchers have found that certain segments of the population may be more prone to problems linked to excessive aluminum intake and accumulation. Seniors and people with impaired kidney function should limit their aluminum exposure and be mindful of how much they consume, including from food and cooking methods. Infants are also vulnerable.19
Cut Back On Foil Usage: Some Quick Tips
While aluminum foil use in moderation is fine, you may prefer to err on the side of caution and cut down your usage of the foil in your cooking. Here are some easy alternatives for you to try:
- Invest in a stainless grilling basket to grill your vegetables on the barbecue, grill, or oven.
- Instead of using foil to catch drips in the oven, use a baking tray or even a stainless steel cookie sheet.
- With foods you can’t imagine baking without foil, it is more a mental leap than anything else. The foods do just fine without the foil. For instance, you can very well bake potatoes without foil. Take a thin skewer and make deep holes that go to the center to prevent any explosions of food and to allow the middle to cook through evenly.
- If you need to keep your oven clean and reduce the effort of scrubbing afterward, use glass dishes that are oven safe. They are much easier to clean and food is less likely to stick to the glass dish than a metal one.
- Buy some reusable skewers and skewer your meat and veggies on it for a mess-free and fun alternative to the foil baked version.
- For an exotic substitute for wrapped foods while baking, experiment with banana leaves – they’ll lend a lovely aroma to the vegetables or meat within and are also biodegradable. So that’s two wins with one simple change.
|↑1, ↑3||Bassioni, Ghada, Fathia S. Mohammed, Essam Al Zubaidy, and Issam Kobrsi. “Risk assessment of using aluminum foil in food preparation.” Int. J. Electrochem. Sci 7, no. 5 (2012): 4498-4509.|
|↑2||Still Cooking with Aluminum Foil? You’ll Want to Read This. Reader’s Digest.|
|↑5||Myths and Facts About Aluminum and Human Health. The Aluminum Association.|
|↑6||Aluminium. Government Of Canada.|
|↑7||Tolerable or acceptable daily intakes, other toxicological information and information on specifications.The Food and Agriculture Organization.|
|↑8||Aluminium. International Programme on Chemical Safety.|
|↑9, ↑11, ↑19||Kawahara, Masahiro, and Midori Kato-Negishi. “Link between aluminum and the pathogenesis of Alzheimer’s disease: the integration of the aluminum and amyloid cascade hypotheses.” International Journal of Alzheimer’s Disease 2011 (2011).|
|↑10||Killin, Lewis OJ, John M. Starr, Ivy J. Shiue, and Tom C. Russ. “Environmental risk factors for dementia: a systematic review.” BMC geriatrics 16, no. 1 (2016): 175.|
|↑12||Martyn, C. N., C. Osmond, J. A. Edwardson, D. J. P. Barker, E. C. Harris, and R. F. Lacey. “Geographical relation between Alzheimer’s disease and aluminium in drinking water.” The Lancet 333, no. 8629 (1989): 61-62.|
|↑13||Tomljenovic, Lucija. “Aluminum and Alzheimer’s disease: after a century of controversy, is there a plausible link?.” Journal of Alzheimer’s Disease 23, no. 4 (2011): 567-598.|
|↑14||Kim, Min Sook, and Lenore S. Clesceri. “Aluminum exposure: A study of an effect on cellular growth rate.” Science of the total environment 278, no. 1 (2001): 127-135.|
|↑15||Alfrey, Allen C. “Aluminum toxicity in patients with chronic renal failure.” Therapeutic drug monitoring 15, no. 6 (1993): 593-597.|
|↑16||NKF KDOQI GUIDELINES. National Kidney Foundation.|
|↑17||De Chambrun, G. Pineton, M. Body-Malapel, I. Frey-Wagner, M. Djouina, F. Deknuydt, K. Atrott, N. Esquerre et al. “Aluminum enhances inflammation and decreases mucosal healing in experimental colitis in mice.” Mucosal immunology 7, no. 3 (2014): 589-601.|
|↑18||Lerner, A. “Aluminum as an adjuvant in Crohn’s disease induction.” Lupus 21, no. 2 (2012): 231-238.|