There is an important nuance when it comes to coffee's health benefits, such as the cancer protective effects. Brewing method does matter. Most studies show clear cancer protection involved filtered coffee. Boiled or unfiltered methods like the French press or espresso allow oily compounds called diterpenes to enter our cup of coffee. At higher consumption levels, these diterpenes have been associated with slightly elevated risk of certain cancers, such as pancreatic cancer and respiratory tract cancers. So why does brewing method have such a profound impact on health outcomes? It comes down to 2 key groups of coffee compounds. On the one hand, coffee is rich in polyphenols. These are powerful antioxidants that can lower dementia risk by as much as 50% and reduce DNA damage.

This is a critical precursor to cancer by around 23%. On the other hand, coffee also contains these fat-soluble diterpenes. If not filtered out, the diterpenes can significantly raise LDL cholesterol by as much as 30 milligrams per deciliter within just a few weeks. This elevates cardiovascular risk regardless of one's perspective on LDL's role in cardiovascular disease. There is no reason coffee should be raising your LDL by this much, so this is best avoided if possible. To fully optimize coffee's health benefits, we need to understand how different brewing methods dramatically change its chemical makeup and ultimately its impact on our health. Coffee contains 2 critical types of compounds we're going to focus on. First, diterpenes, specifically cafestol and kahweol.

These are fat-soluble molecules that naturally are found in coffee beans. The problem with these diterpenes is that they significantly raise LDL cholesterol. In fact, studies have found that people who regularly drink unfiltered coffee, like from French press, espresso, or boiled coffee, it can raise their LDL levels by roughly 10 to 30 milligrams per deciliter within just a few weeks. And that does increase cardiovascular disease risk. There's also links between higher diterpene exposure from unfiltered coffee with slightly elevated risk of certain cancers. Second, and more beneficially, coffee beans are rich in polyphenols, primarily the chlorogenic acids. Polyphenols are powerful antioxidants that reduce inflammation, oxidative stress, protect us from chronic diseases.

Unlike diterpenes, polyphenols are water soluble, so they dissolve in water and easily pass through paper filters. Here's why this chemical difference matters. Brewing methods dictate how much these compounds end up in our coffee. Unfiltered methods like espresso, French press, boiled coffee, or stovetop percolators retain the oily diterpenes. For perspective, espresso contains around 1,100 milligrams of cafestol per liter. Turkish boiled coffee contains around 900 milligrams per liter, while French press and moka pots contain 70 to 90 milligrams per liter. Practically, that means one espresso shot has about 30 milligrams of cafestol, and a typical cup of coffee from other unfiltered methods have between 10 and 200 milligrams.

In contrast, filtered coffees like traditional paper drip, instant cold brew trap these diterpenes in the filter, essentially eliminating their negative effects while still preserving beneficial polyphenols. Recent studies have shown that even workplace coffee machines, which usually lack proper filtration, deliver significantly higher diterpene concentrations. between 140 to 170 milligrams per liter compared to filtered coffee prepared at home, which often shows undetectable levels. As a side note, I do want to mention that many traditional paper drip coffee machines do run hot water through plastic. In other words, you know, hot water going to plastic will accelerate the release of microplastics into your beverage as well as their plastic-associated chemicals.

So if you are going to do a filtered coffee, pour over, is probably your best bet, doing something into a glass container and not having the hot water touch plastic. On a similar note, if you're drinking espresso, those espresso pods are also plastic. And so having hot water go through those pods is also releasing microplastics and their associated chemicals into your beverage as well. Just something to keep in mind. So given everything we've discussed so far, it might not surprise you that the brewing method you choose can dramatically influence coffee's health impact. But what's truly fascinating and maybe surprising is just how distinct these outcomes can be depending on how you prepare your coffee.

Filtered coffee consistently stands out as the best choice for longevity and overall health. A major cohort study found that regularly drinking filtered coffee was linked to about a 15% lower all-cause mortality compared to drinking no coffee at all. Similarly, regular consumption of filtered coffee, around 2 to 5 cups per day, is strongly associated with a 20% lower risk of cardiovascular-related mortality compared to drinking no coffee at all. Neither of these protective associations were observed with unfiltered coffee methods like French press, likely due to their cholesterol-raising diterpenes. And when it comes to cognitive health, the data is even more striking. Consistently drinking filtered coffee can lower your dementia risk by as much as 50% compared to not drinking coffee.

But these benefits diminish sharply or even reverse when using unfiltered brewing methods, particularly when consuming extreme quantities of coffee. For instance, heavy consumption of boiled coffee like Turkish coffee— we're talking extreme, around 8 cups or more per day— is linked to a nearly double risk of dementia compared to moderate drinkers, likely due to those diterpenes which I mentioned earlier. They're raising LDL cholesterol. High intake of boiled coffee also shows potential association with increased risk for specific cancers, as mentioned earlier: pancreatic cancer, respiratory tract cancers as well. So it really highlights the need for moderation and caution when you're drinking boiled coffee. You do not want to go to that extreme level of drinking 8 cups per day.

I would say, given the otherwise strong evidence for coffee's anti-dementia effects at more normal doses, either excessive intake itself or specifically boiled coffee is likely the culprit here with respect to increased dementia risk, because as I mentioned earlier, filtered coffee is associated with as much as a 50% lower dementia risk compared to not drinking coffee. Now, espresso is somewhat of a special case. While espresso does still contain those cholesterol-raising diterpenes, moderate espresso consumption, like 2 to 3 servings daily, remains strongly associated with a lower overall mortality, likely due to its exceptionally high antioxidant density per ounce. Espresso's robust polyphenol content might actually balance out some of the diterpene-related downsides.

Providing that you're maintaining a moderate consumption of espresso. Instant coffee, which is often overlooked, actually holds up remarkably well against filtered coffee. Studies consistently find that instant coffee drinkers also benefit from a lower all-cause mortality, as well as a significant protection against diabetes and cognitive decline. That's probably because instant coffee also has high antioxidant levels similar to traditionally brewed coffee. So to sum it up, filtered coffee really emerges as the best way to brew coffee. It offers the strongest, most consistent health benefits across cardiovascular, metabolic, cognitive, and longevity outcomes. Espresso and instant coffee also provide substantial protective effects at moderate consumption levels.

Unfiltered methods, especially boiled coffee or very heavy French press consumption, require greater caution due to their cholesterol-raising diterpenes And at very, very extreme high levels, 8 cups or more a day, potential cognitive risks, even though moderate intake probably still offers beneficial polyphenols and antioxidants.