3 slices of moldy bread sitting on top of one another
Julie Hambleton
Julie Hambleton
December 16, 2023 ·  3 min read

Please Stop Eating The ‘Clean’ Bit Of Moldy Bread, It’s Not Safe

Have you ever found mold on your bread, scraped it off, or cut it away and still ate it? Or, did you toss that slice but then grab another slice from the same loaf? Well, I hate to be the one to tell you, but you could potentially be ingesting some pretty bad toxins – even deadly ones (if at a high dose) – into your body. This is why you should never eat moldy bread. Don’t worry, you’re not dying from a slice of old bread, but it’s not harmless either.

What’s Actually Inside Moldy Bread

We eat moldy and fermented foods all the time. Some cheeses, soy sauce, and more contain molds that are perfectly safe for you to eat. Some molds, which are actually fungi, are even good for you, like the mushrooms you can buy at the grocery store. Not all molds, however, are created equal and should not be eaten. This includes moldy bread. (1)

The reason for this is that the mold you see on the surface of bread is sort of like an iceberg – it’s just the beginning. By the time it appears as a blue-green fuzzy growth on the surface, it already has an extensive network spread throughout the bread – you just can’t see it. (1) Visible mold means that the fungus has reached its reproductive stage. It is spreading mold spores quickly throughout the entire slice of bread, and likely has already begun invading the entire loaf. (1)

What Kinds Of Toxins Are In Moldy Bread?

While many molds and fungus can be benign and completely harmless, there are many that aren’t. The problem is, there are so many species of mold that it is impossible to know which it is just by looking at it. (1) Some of the molds may cause you to develop allergies, others might make you a bit sick or upset your stomach. Some, however, are highly dangerous and can be fatal. Mycotoxins are one of these molds and can be found growing on bread and other food items. (2)

Read: People Are Turning Vegan After Watching Seaspiracy On Netflix, But How Accurate Is The Documentary?

All About Mycotoxins

Mycotoxins are naturally occurring toxins in some molds. These molds grow on several food products and thrive in warm, humid conditions. Unfortunately, these toxins can cause several adverse health effects in both humans and animals. (2)

Mycotoxins can cause both acute (short-term) and long-term health effects. Short-term, they can cause a person or animal to become severely ill shortly after consuming a contaminated food item. Long-term they can cause many health problems, including cancer and immune deficiencies. (2)

So far, scientists have identified several hundred different types of mycotoxins. Each has its own effects and ranges widely in severity. As already mentioned, without the ability to actually test them in a lab, you never know which one might be growing on your bread. (2)

How To Prevent Mold Growth On Bread

We know that wasting food is bad, but when it comes to mold on food, the best practice is, unfortunately, to just throw it away. To minimize both the risk of having mold grow on your bread and to keep it fresher for longer, you can (2):

  • Pay attention to expiry dates
  • Don’t buy more than you can eat
  • Store bread in air-tight bags in the freezer

The old saying “when in doubt, throw it out” fits best here. The same goes for any other grains, soft cheeses, fruits, vegetables, yogurts, and really any other food product that you find with mold on it. A little food waste is better than severe illness, long-term health complications, and risk of death.

Keep Reading: Scientists Developing Contact Lenses That Can Treat Diabetes

Sources

  1. Never Eat The ‘Clean’ Part Of Moldy Bread.” Youtube. Science Insider. September 12, 2018.
  2. Mycotoxins.” WHO