What Happens If You Eat Moldy Bread?

No-one likes having to throw away uneaten food. However, around a third of all food produced never gets eaten. One widespread reason to throw away your groceries is that they’ve started to grow mold.

Some forms of mold that can grow on your food are harmless to eat. Some even make the food tastier, such as the specialized molds used to make gorgonzola and camembert. But what happens if you eat moldy bread? Is it safe to just scrape away or cut out the moldy part and eat the rest?

What Is Bread Mold?

There are several different types of mold that can grow on your bread, including:

  • Aspergillus
  • Botrytis
  • Fusarium
  • Mucor
  • Penicillium
  • Rhizopus

Depending on which type of mold is growing on your bread, you might find patches of black, green, gray, yellow or white. These colors can change over time, and so they are not enough for you to work out which type of mold is growing on your bread.

Mold is a fungus, and the fuzzy patches you see on your loaf are the spores that the fungus uses to spread and reproduce. When you put the molds under a microscope, they look very similar to mushrooms, with the spores sitting atop stalks, ready to fire out and spread.

Is the Mold Bad for You?

Most molds that grow on food are relatively harmless to humans, but some can potentially cause issues. Depending on the type of mold that is growing, it might do nothing, or it might just affect people with specific allergies. Mold can also be dangerous to those with weakened immune systems, such as diabetics.

But moldy bread can also contain toxins that are seriously harmful to anyone’s health. Just inhaling the spores can be enough to cause issues. If you have an allergy, this can be a potential trigger for asthma. And if a person with allergies eats the mold, it can lead to dangerous and potentially life-threatening reactions, like anaphylactic shock.

Diabetics with poorly-controlled symptoms are also at risk of contracting an infection if they inhale Rhizopus from bread. While rare, this infection can be very dangerous, and possibly even fatal.

It’s Better to Throw It Away

The problem with how mold reproduces is that the fuzzy spores that you see on your bread are just the tip of the iceberg. Even before it is visible on the surface, the mold can and likely will have spread its roots throughout the bread. Scraping it off or cutting it away unfortunately won’t be enough to ensure that your bread is mold-free.

That’s why the general consensus is that it is safer to throw away the entire loaf if you find mold growing on it. While it might seem wasteful, you could potentially be saving yourself from a lot of future trouble.

Some species of molds that grow on bread can produce poisonous substances called mycotoxins. They are especially highly concentrated in bread that has large amounts of mold on it. These toxins can cause digestive issues, as well as other illnesses in both humans and animals, so you shouldn’t be giving moldy bread to your pets either.

The most notorious of the mycotoxins, aflatoxin, is produced by Aspergillus molds, which can grow on your bread. If you keep eating it, you may be increasing your chances of developing cancer.

How to Stop Mold from Growing

Most breads that are made without preservatives will only last between three to four days, which is why people have tried a few different methods of preserving bread’s lifespan.

Store Your Bread Properly

While the baking process generally leaves the bread free from mold and bacteria, it doesn’t take long for them to gain a foothold once more. Whenever the bread is exposed to air, there is a chance that spores can land on it and begin to spread. As molds prefer warm and humid conditions in which to reproduce, keeping the bread somewhere that doesn’t fit that description can help you preserve it for longer.

The most readily available methods include:

  • Put the bread in the freezer – Putting it in the refrigerator will slow the growth of mold, but it won’t stop the bread from going stale. It also tends to dry it out. Freezing the bread halts mold growth while minimizing the changes to the texture. This method is especially useful for gluten-free bread, which is usually moister and contains fewer preservatives.
  • Keep it covered – Making sure your bread isn’t exposed to the air will help to reduce the number of mold spores that can land on it, which is especially useful when making your own bread. Just be sure to let the bread cool thoroughly before packing it away, to keep it from getting soggy.
  • Keep the packaging dry – Wipe away any moisture you find inside the packaging with a clean cloth or kitchen roll, as the dampness will encourage the mold to grow.

While many brands of bread come with special forms of packaging, such as vacuum sealing, this is only effective until the bag is opened. After that, it can be contaminated by spores.

Choose Bread Made with Preservatives

Most home-made breads are made without preservatives, which is why they have such a short lifespan. Much effort has been put into finding ways of helping bread to last longer. While ingredients like cloves and cinnamon can be used to reduce the growth of mold, they generally have quite strong flavors, so their use is fairly limited.

Most bread found in the supermarket is made with chemical preservatives such as sorbic acid and calcium propionate, both of which help to slow the growth of mold. Another common option is to purchase breads like sourdough, which are made using lactic acid bacteria. The acids produced by these bacteria also work to slow down mold.

Better No Bread Than Dead

What happens if you eat moldy bread? Sometimes, if you’re low-risk, and it’s the right kind of mold, nothing at all. But, considering the risk factors involved in eating moldy bread, especially for people who have compromised immune systems or allergies, it’s generally not worth taking the chance. Wasteful as it seems, it’s better to throw out a moldy loaf, as it can make both you and your pets ill.

 

References:

http://www.fao.org/save-food/resources/keyfindings/en/
https://www.ncbi.nlm.nih.gov/pubmed/30301164
https://www.ncbi.nlm.nih.gov/pubmed/26980564
https://www.fsis.usda.gov/shared/PDF/Molds_on_Food.pdf?redirecthttp=true
https://www.ncbi.nlm.nih.gov/pubmed/19772765
https://www.ncbi.nlm.nih.gov/pubmed/26140270
https://www.ncbi.nlm.nih.gov/pubmed/11563743
https://www.ncbi.nlm.nih.gov/pubmed/28904924
https://www.ncbi.nlm.nih.gov/pubmed/29674435
https://www.ncbi.nlm.nih.gov/pubmed/28240164
https://www.ncbi.nlm.nih.gov/pubmed/28636450