Most of us love to begin our mornings with a tall cup of coffee, jump starting our day (especially in the beginning of the week). Recent studies have shown, however, that along with a shot of caffeine, many of us may be ingesting harmful toxins, brought into our coffee by certain types of mold.
The particularly worrisome types of contaminants found in coffee are known as mycotoxins and ochratoxins, and neither one of them are good news. These toxins come from mold in your coffee, and nearly all low-quality varieties are afflicted with them. According to Bulletproof Coffee's Dave Asprey, this is particularly a problem in bargain coffees and blended types. In both instances, a higher percentage of moldy beans can be used, and in the case of blended coffee, cheap beans sourced from various locales make the introduction of toxins a near certainty.
Recent studies have confirmed the presence of these toxins in a wide variety of coffee beans. One found that almost 92% of green coffee beans were contaminated with some degree of mold, while another concluded that 52% of green coffee beans and 50% of brewed coffees evinced contamination. The first study also examined beans prior to processing, which can help to increase mold growth.
Contamination need not only come from the beans involved in brewing, mind you. As Consumer Affairs points out, coffee makers are reliably moist environments, which are known to facilitate the growth of mold and bacteria. They cite a 2011 study from NSF International, which showed that almost half of all coffee brewers had some form of yeast or mold growing in their reservoirs. If you own an instant cup maker, don't think your machine is immune to this process: these studies are not limited to filter-style brewers, and have shown that Keurig machines and their ilk are just as susceptible to the same issues of contamination.
Kelly Reynolds, a germ specialist from the University of Arizona, agreed with the NSF study, pointing out that human bodies can deal with the presence of contaminants in measured doses.
"Coffee makers are certainly a moist environment where mold and bacteria are known to grow in high numbers; our bodies can deal with them, but at some point they'll grow to levels high enough to cause sickness."
Other researchers have pointed out that coffee makers are particularly susceptible to these issues, since mold and mildew can grow on hard plastic surfaces (like the interior of a reservoir). They point to an increasingly bitter taste in your coffee as evidence that it may be contaminated.
Key to these studies, however, is an understanding of how much of these contaminants a coffee drinker is likely to be taking in. While none of these toxins are preferable, many of them are consumed below tolerances where they become an issue, as Authority Nutrition points out. While the buildup of toxins must be examined (just as we have previously discussed on the Green Conscience Blog, with issues of off-gassing and sick building syndrome), mycotoxins in trace amounts may be so far below safety limits as to be practically of no significance.
That is not to say, however, that they are without their negative effects: mycotoxins have been linked to cancer, kidney disease, cardiomyopathy, and even brain damage. Ochratoxin A, meanwhile, is known to cause cancer and damage the immune system, negatively impacting the kidneys as well.
Mycotoxins are nothing new, and coffee makers are well aware of the issue. While it always pays to investigate the substances you take in and proceed with your own due diligence, the positive effects of coffee are likely to outweigh the negative impacts of mold and toxins in the short run. In the long term, however, experience shows us that it never hurts to limit exposure to contaminants. Luckily for those of us interested in a sustainable lifestyle, there is no shortage of options (like Bulletproof Coffee or various herbal replacements) that can make limiting mold in your coffee a painless procedure.
Hi! I'm Karen Totino, owner of Green Conscience Home. I'd love to hear your thoughts on any of our posts, so comment away! One of my goals is to get the community discussing some of these eco topics, and hopefully help each other out!