A recent article in Cell showed that broccoli and related vegetables such as cauliflower and cabbage contain chemicals called glucosinolates that bacteria in the human gut turn into isothiocyanates, compounds with protective effects against certain cancers. That’s of no use to me obviously. I already have cancer, despite having been a happy eater of broccoli for ages. Maybe I lack the bacterium whose enzymes perform the chemical reaction. It’s called Bacteroides thetaiotaomicron, and if you have a hard time reading the name, here’s the Greek version: θιο. That’s more like it.
If there are foods that help prevent cancer – and there are many more besides cabbage and broccoli – maybe there are also foods or supplements that help the body fight cancer. They could boost the body’s immune response, augment the effect of chemotherapy, or be directly toxic to cancer cells. Polysaccharide K (PSK), derived from the mushroom Trametes versicolor, is such an example. It’s been used to supplement chemotherapy in Japan for many years. Clinical trials have shown improved survival and slower disease progression in patients. PSK is not available in Switzerland, but I have now purchased two tubs of Trametes capsules and will start self-supplementing. I don’t expect it to help, but it’s unlikely to hurt. Even if it does hurt, I’m in such a bad place that it won’t matter.
For something more scientific than a poorly regulated supplement, I obtained a review with the enticing title Dietary modifications for enhanced cancer therapy, which appeared in Nature a few weeks ago. My expectations were high, but the review did not contain any silver bullets. No word of polysaccharide K or other polyglycans from magic mushrooms. In fact, it's not about supplements at all. The article focuses on the omission of various nutrients. Trained in the study of scientific literature, I skipped straight to the discussion after reading the somewhat vacuous abstract. The authors conclude that “there are still no clear guidelines or recommended regimes of dietary modification for patients with cancer.” I could have stopped right there and drowned my pain in another glass of red wine – wasn’t that considered the recipe for a long and healthy life at some point? – but I wanted to know a bit more.
Towards the beginning of my first chemotherapy program, when I recovered from surgery and my doctors talked about retaining or even gaining weight, a friend of mine had mentioned fasting as a strategy proposed by Russian scientists that no one in the West is aware of. It seems someone is aware after all, because the review in Nature states that “the combination of prolonged fasting cycles (48-60 h) and chemotherapy significantly improved the response to therapy in mouse xenograft models of breast cancer, melanoma, glioma and neuroblastoma.” Now that’s mice and not humans and a bunch of cancer models that are not colon cancer, but it’s interesting anyway.
The original publication (not written by Russians) even claims that “cycles of starvation were as effective as chemotherapeutic agents in delaying progression of different tumors and increased the effectiveness of these drugs”. That’s a strong statement and worthwhile to consider in its entirety. From the first half you might ask why bother with chemotherapy if fasting is as effective. Surely it is cheaper and has fewer side effects. Is the evil pharmaceutical industry talking us into something we don’t need? The second half tells us that starvation might potentiate the effects of chemotherapy, which is quite something.
Why might periodic starvation be good? Fasting induces healthy cells to reallocate energy towards maintenance pathways at the expense of reproduction and growth. Chemotherapy targets reproduction and growth. In fasting patients, cancer cells, which can’t activate the same stress resistance, bear the full brunt of chemotherapy. In addition, starved cancer cells might try to compensate for the lack of nutrients by increasing translation, which consumes even more energy and might promote oxidative stress, DNA damage and eventually cell death.
What might this look like in practice? Patients fast for two to three days before chemotherapy and for 24 hours afterwards. This means no food at all, only water. The paper claims that this is well tolerated and might also reduce side effects because healthy cells become resistant to the drugs. The mice in the study regained their weight after five days of feasting. I don’t know how I might function under these conditions. Could I still work? What about exercise? I’ve never tried anything like this, but at this point, it seems worth a shot – or at least a discussion during the consultation at the University Hospital in Zurich next week.
But maybe it’s all for nothing? The article suggests that fasting after chemotherapy is important to protect healthy cells. To minimize toxicity when refeeding begins, the duration of fasting should be proportional to the half-life of the drug. Here I see a serious problem. My chemotherapy takes 48 hours. I cannot possibly fast 48 hours before chemotherapy, 48 hours during chemotherapy and then another 24 hours after chemotherapy. That would be five whole days. I wonder what the doctor will say.
Now I didn’t even get to read the review that triggered this post. Something for another time.
0 comments:
Post a Comment