When you open a can of sardines, tomato, soda or infant formula, you think about the food, you don’t usually think about the can. But what you should actually be thinking about is precisely the can, and not the food.
How Are Food And Beverage Cans Manufactured, And Why Should You Care?
Food and beverage cans are basically made of aluminum, steel, or aluminum alloy. Most metal beverage cans manufactured in the United States are made of aluminum(1). In Europe and Asia, about 55% are made of steel and about 45% are made of aluminum alloy (usually containing about 95% aluminum). Steel cans often have a top made of aluminum.
Cans made with aluminum are usually (but not always) coated internally to prevent the aluminum from oxidizing and interacting with the food. This is why most tin cans are lined with products called epoxy resins.
How do you know if there is a lining in your can? Simple. If there is a BPA containing lining, the can will have a white substance inside, just like you can see on the above picture.
And now comes the juicy part: Bisphenol A is used to manufacture a common class of epoxy resins, the ones that line the cans of our foods and beverages. Bisphenol A (BPA) is widely used in plastic containers, in the inner lining of metal cans, soda cans, and other food packaging. And the problem is that BPA is toxic to humans.
Why Is Bisphenol A Toxic And How Can You Avoid It?
There are about 200 studies that show Bisphenol A can be harmful for our health. BPA is a chemical that may mimic human estrogen and it has been linked to breast cancer and early puberty in women.
BPA has actually been used in plastics for more than 50 years, although it has been known since the 1930’s that it acts as an endocrine disruptor and may have adverse effects on people’s health. But recent studies have shown that BPA is even a greater problem in cans than in plastic containers.(2)
BPA is at unsafe levels in one of every 10 servings of canned foods (11%)
and one of every 3 cans of infant formula (33%)
Source: Environmental Working Group
Research from the Harvard School of Public Health has shown that canned foods and beverages may increase your Bisphenol A levels by 1,000 percent in 5 days only. (3)
Are Canned Foods And Beverages Without BPA Safer?
Not all cans contain BPA, because not all cans are lined with epoxy resins, and some cans are lined but with products that don’t contain BPA (there are very few of them right now, though). But you should know that most cans do contain BPA.
Even some health conscious canned foods producers who don’t use Bisphenol A recognize that they still include it in canned tomato products because it prevents the aluminum from interacting with the tomato.
Now, does it mean that cans without any lining are safer? Not really. If producers wanted to prevent food from interacting with the metal of the can, there must be a good reason. And the reason is that aluminum that goes into your food is toxic.
This is especially true for products that contain acidic substances: tomatoes, vegetables preserved with citric acid, and sodas. However, canned sardines or tuna with oil, for instance, are not acidic and will interact a lot less with the metal of the can.
Anyway, there is still aluminum in the cans (most of them), and with or without BPA, this doesn’t make canned goods a healthy food.
So, What Should You Do?
The best approach is to cut out canned foods and beverages from your diet or at least highly limit their consumption. You will avoid being exposed to endocrine disruptors and also to aluminum, which has been proven to be linked with Alzheimer’s disease (4) and many other health problems.
However, don’t panic. Our body is very powerful, and it has the ability to break down BPA if you help him a bit by eating the right types of foods.
Research has shown (5) that Bifidobacterium breve strain Yakult (BbY) and Lactobacillus casei strain Shirota (LcS) can help eliminate BPA. These good bacteria can help, and they can be found in Yakult, in lacto-fermented products such as vegetables, kefir, or organic live yogurt.
This doesn’t mean that you should go on consuming canned goods, but it means that the occasional (the key word here is occasional) can of coconut milk, sardines, or tuna won’t harm you if you drink some kefir with it. The problem starts when you consume a can of soda every day, or eat canned soup every other day. These are of course not scientific examples but I’m sure you get the picture.
What do I do? I am very careful with canned foods and only buy them when I can’t find the food fresh or in glass containers. This means, we might actually open 1 can per week or even less. And we never, ever drink any can of soda.
We also consume homemade lacto-fermented vegetables such as mango chutney, as well as live organic goat milk yogurt and some homemade lacto-fermented beverages like ginger ale. And quite frankly, I’m no longer worried about aluminum or BPA, and that’s a really good thing!