Mushrooms Block Cancer and Boost Immunity, Experts Say

Glenwood Springs —The kitchen counter is a battlefield of color. Tomatoes, peppers, leafy greens — the usual suspects for anyone trying to "eat the rainbow" as the nutritionists say. But standing there, a bowl of brown cremini mushrooms sits quietly, unassuming and pale. They don’t fit the vibrant aesthetic of a health food Instagram post. Yet, according to a new column by Feinsinger in the Post Independent, they might be the most important thing on that counter.

This is the 13th and final entry in a series exploring Dr. Michael Greger’s "Daily Dozen," a checklist of foods Greger argues are essential for optimal health. The previous 12 entries covered the usual suspects: berries, beans, greens. But mushrooms? They get their own spotlight. Not because they’re vegetables, but because they’re fungi, and they bring a different kind of firepower to the immune system.

Feinsinger wrote in the Post Independent that while fruits and vegetables rely on intense pigments for their antioxidant punch, fungi operate on a different frequency. They contain ergothioneine, an amino acid with potent antioxidant activity. It protects cells against free radicals. Mushrooms have a higher level of this compound than any other food on the planet. That matters because free radicals are the microscopic vandals that damage DNA, and damaged DNA is often the precursor to cancer.

But it’s not just about antioxidants. The column points to a process called angiogenesis — the formation of new blood vessels. Cancer cells need to build their own blood supply to multiply and metastasize. They secrete promoters to get the job done. Compounds found in mushrooms block this process. They starve the cancer cells. It’s a quiet sabotage, happening at the cellular level, every time someone sautés a portobello.

There’s a specific angle here for women, too. Mushrooms contain a natural aromatase inhibitor. Aromatase is an enzyme involved in estrogen production, and high levels of estrogen increase the risk of breast cancer. Aromatase inhibitors are already used as chemotherapy for breast cancer, but nature packaged the same mechanism into a button mushroom. Feinsinger notes that Asian women have a much lower incidence of breast cancer than those on a Western diet, and part of the reason is thought to be the sheer volume of mushrooms in their daily meals. It’s a dietary pattern, not a magic bullet, but the correlation is hard to ignore.

Then there’s the practical stuff. Inflammation drives asthma, heart disease, and a host of other chronic conditions. Mushrooms have anti-inflammatory properties. They are also one of the few food sources of vitamin D, the "sunshine vitamin," which is crucial for bone health and immune function. Dr. Joel Fuhrman, author of Eat to Live, is cited in the column for noting that mushrooms contain powerful phytochemicals linked to decreased risk of chronic diseases, especially cancer.

Greger suggests using mushrooms as a "chewy replacement for meat." He recommends drizzling balsamic vinegar over them and grilling them over low heat, turning frequently. It’s a simple instruction, but it changes how you view the ingredient. It’s not just a garnish for a steak; it’s the main event.

There are two caveats, though. First, don’t eat them raw. Raw mushrooms contain a mild toxin that is destroyed by cooking. Morel mushrooms, in particular, have a higher level of this toxin. Even when cooked, morels can release this toxin if combined with alcohol. Second, there’s the arsenic question. Arsenic is often present in chicken feed, and some commercial mushrooms are grown with fertilizer containing chicken manure that may contain arsenic. However, the column assures us that the amount of arsenic people receive from eating the quantity of mushrooms most people consume is not enough to be problematic. It’s not a reason to avoid them; it’s a reason to keep eating them.

The bottom line, according to Feinsinger, is that mushrooms are good for you. Eat them two or three times a week. It’s a small change in a grocery cart, but it’s a big shift in how we fuel our bodies. The next time you’re at the market, past the bright red berries and the deep green kale, take a moment with the pale, humble fungi. They don’t shout. They don’t need to. They’re busy doing the work.