People are flipping out over the new Netflix documentary, "What The Health." While I am a proponent of a plant-heavy diet, I am automatically skeptical of claims that a foods are a miracle cure. I prefer to get my nutritional and health advice from my doctors, and if I see some outlandish claim on the internet, I investigate it on a site like "Science-Based Medicine" – a site I will wholeheartedly recommend to anyone. They had their own thoughts on "What The Health":
But what I want to explore today is an article by Vox, and one particular criticism in general.
"6) Five to 10 percent of cancer is caused by genetics, and the rest is caused by food. Repeatedly in the film, Andersen overstates the role food plays in driving disease. What we eat is only one factor affecting our health. Some of the best research we have on contributors to cancer risks suggests some 30 percent of new cancer diagnoses could be cut by improving lifestyles — but not just our diets. Behaviors that cut a person’s cancer risk involve never smoking, cutting down on alcohol, keeping a healthy bodyweight, and exercising."
I've encountered the "5-10% of cancer is caused by genetics so the rest must be caused by lifestyle" fallacy before and it irks me for the following reasons:
- Cancer is not a singular disease. Look at the National Cancer Institute website (https://www.cancer.gov/types). How many types of cancer do you see? A lot, right? Now think about this. For most every type, there are different subtypes. Take breast cancer. Within that cancer type, you have ductal carcinoma, lobular carcinoma, inflammatory carcinoma, hormone positive, triple negative, Her2 positive that may or my not also be hormone positive. You have postmenopausal, premenopausal and male breast cancer. And that's just the most common subtypes. Now think about all the different kinds of cancers and all the different kinds of kinds of cancers. Do they all have the same risk factors? Does smoking contribute to multiple myeloma in the same numbers it contributes to lung or throat cancer? Of course not. So to say "cancer is caused by meat/sugar/carbs/dairy" is, at best, a huge oversimplification, and at worst, outright false.
- Environment, meaning exposure to carcinogens we can't control, such as those in the air and water, are a very unexplored area of research. I am not a ZOMG EVIL CHEMICALS person because, guess what? Everything contains chemicals. I do believe there's environmental causes of cancer we haven't been able tease out, but that's not the result of some massive conspiracy or cover-up. It's because it's just plain hard to isolate single factor over such a large and diverse group as cancer patients. See this article from Newsweek which explains why it's so hard to prove the existence of "cancer clusters." (http://www.newsweek.com/2016/07/29/geographic-cancer-clusters-industrial-polluters-481423.html)
- Sometimes cancer is the result of chance, or bad luck, as some studies have shown. While the oft-quoted Hopkins study in 2015 was widely criticized, the scientists came back this March to explain further.(https://www.scientificamerican.com/article/most-cancer-cases-arise-from-bad-luck/). As they said, they are not giving people a license to smoke, drink excessively, never exercise and eat donuts all day, but they are explaining why cancer arises in people who are young with no family history and who lived healthy lifestyles. I know many people who fit that description.
- 5-10% of cancer caused by genetic mutations refers to KNOWN mutations. BRCA is the most common of the known mutations and those who have a personal or family history who meet a certain criteria are offered testing. But few are offered testing beyond that, such as testing for the CHEK, ATM, germline p53 and other lesser known mutations. So there are likely lots of people walking around with cancer-causing mutations that don't even know. Then there are Variants of Unknown Significance of a mutation, which is basically "it's likely to be ultimately negative so we treat it as a negative but we can't know for sure (I've tested for a few of those in my large-panel genetic testing). Then there are mutations yet to be discovered. I've known far too many young cancer patients with an extensive family history who came up negative on genetic testing to believe that we've found all the cancer-causing mutations there are.
As for my personal theory on why I got cancer at 28? A combination of genetics (mother, mother's aunt and paternal grandmother all had breast cancer and that's in a very male-dominated family) and super shitty luck (why I got it so young). I'm not ruling out that there's also some lifestyle and/or environmental factor at play, but there's nothing obvious to me there, and until science proves there is, I'm going to continue to enjoy my occasssional cheeseburger.