Coffee drinkers across California are dumbfounded by a judge’s decision to stick cancer warnings in coffee shops across the state under the auspices of the state’s notorious law known as Proposition 65.
Judge Elihu Berle’s ruling stems from the presence of acrylamide in roasted coffee beans. Acrylamide is a naturally occurring chemical, released in foods cooked to high temperatures. Berle’s ruling that products containing acrylamide would have to carry cancer warnings is due to the fact that the International Agency for Research on Cancer (IARC) found the substance to cause potentially cancer – albeit only to lab rats who were given extraordinarily large doses.
Researchers from around the country have questioned whether the warnings are really necessary and whether their imposition might not harm more than it helps. The goal of Proposition 65, to provide consumers with data allowing them to make informed decisions about the products they use, is a commendable one – but critics argue that the overuse of Prop 65 is spreading paranoia, and ultimately causing people to disregard its warnings.
Weighing up the risk
In a world fraught with risk, exercising control over the things we eat and drink is one way of improving our long-term health outlook.
Author and activist Michael Pollan famously summed up his health advice in seven words: ‘Eat food, not too much, mostly plants.’ But as we’re besieged each day with infinite dietary choices, it can be difficult to know what to consume and what to kick to the kerb.
There’s plenty of consensus on the need to eat more fruit and vegetables, while limiting our intake of red meat, saturated fats and alcohol. But there’s also no shortage of conflicting reports about whether the moderate consumption of items like red wine, chocolate and coffee helps or hurts us more.
Luckily, we don’t have to make all these judgements ourselves. That’s where organizations like IARC come in, promising to do the necessary research legwork and offer consumers guidance. On paper, IARC’s credentials look impeccable: the agency has been assessing the presence of carcinogens in everyday substances for decades and categorising their health risks.
There are a couple of problems, however. IARC’s scientific credibility has recently been called into question, including by U.S. Congress, after a series of explosive Reuters reports suggesting that the agency had manipulated data and left out key findings in its reviews of industrial chemical benzene and popular herbicide glyphosate. Another issue is that out of almost 1,000 substances IARC examined over the last 40 years, only one, caprolactam (an ingredient in the nylon used in yoga pants), has been deemed ‘probably not’ likely to cause cancer.
The danger of equivalence
Naturally, not all carcinogenic substances are created equal. Many would be surprised to learn that IARC ranked processed meats like sausages and bacon, as well as Chinese salted fish, in the same carcinogen category as asbestos, tobacco smoke and arsenic.
Neither IARC nor warning programs like that provided for under Proposition 65 adequately recognize that even among substances classified as ‘definitely’ carcinogenic, there are drastically different levels of risk. In the UK, for example, if no-one smoked, there would be 64,500 fewer cases of cancer a year—while if the entire British population abstained from both processed and red meat combined, there would only be 8,800 fewer cancer cases.
This does little to highlight the fact that smoking is deeply harmful, while moderate consumption of red meat boosts iron intake. This tendency to ignore any potential benefits of a substance affects the assessment of coffee, too, which has been found to reduce the risk of diseases such as liver and endometrial cancers, cardiovascular disease, and type 2 diabetes.
Trust the experts?
Despite this lack of nuance and rising concerns about IARC’s scientific integrity, the agency still has a lot of influence on international policy. Its classifications have historically been considered sufficient justification to include a substance on the Proposition 65 list, even in the absence of any other scientific evidence attesting to that substance’s carcinogenicity.
There are signs that this blind allegiance to IARC’s categorizations is finally wavering. In February, a federal judge halted plans to plaster Proposition 65 warnings on products containing the herbicide glyphosate. The judge determined that the standard Prop 65 warnings, which uses the language “known to the State of California to cause cancer,” would be “misleading at best” given that IARC was the only major organization in the world to find that glyphosate was carcinogenic.
There’s definitely more of a scientific consensus on acrylamide, though the amount found in most foodstuffs is generally thought to be harmless. The studies which found that acrylamide increased cancer risk in rodents, for example, gave them doses up to 10,000 times what humans would normally consume in their diet. Some have speculated that you would have to eat nearly 200 pounds of French fries a day to have an appreciably higher risk of getting cancer from acrylamide. Even the American Cancer Society admits that there are currently “no cancer types for which there is clearly an increased risk related to acrylamide intake.”
Is it so bad to be cautious?
Some would argue that, no matter how small a risk, it’s better to fully warn consumers. If Prop 65 is encouraging consumers to be cautious and aware of what they’re ingesting, is that such a bad thing?
The issue is that being overly cautious exposes consumers to a separate category of risks. By posting cancer warnings on an ever-expanding list of substances, their message may become muddied, as consumers could wrongly equate a 40-a-day cigarette habit with a three-cups-a-day coffee craving.
No lifestyle can protect you completely from cancer, although you can mitigate risk by eating a balanced diet, watching your weight and not smoking. It’s even been suggested that stress can raise cancer risk—all the more reason to relax and savour that cup of java without feeling guilty.