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Love coffee, want the convenience and health benefits ?

Let’s take a look at one of the many household items commonly found that may be doing some damage to your health…..yep the Keurig machine.

There are tons of ways to purchase, grind, extract the coffee let alone serve it together with a host of additives.

But what’s the best option when you look from a science based perspective ? Clearly it depends as there are a number of thoughts from is it organic (free of pesticides) dark or light roast, mold containing, caffeinated or not, and the list goes on.

+/- Health Considerations:

On the positive side of the equation consider the reduction of inflammatory and oxidative stress-related diseases. These can include, obesity, metabolic syndrome and potentially  type 2 diabetes.  There is an associated with a lower incidence of several types of cancer, including those in the  liver and prostate.  What about its ability to  reduce the risk of all-cause mortality ? Did you know that 3-5 cups of coffee per day is associated with a 15% reduction in the risk of cardiovascular disease  (CVD) ?

You might remember  some time ago there was a scare from the state of California  with an issued Prop 65 warnings on coffee. How did this come about ? There is concerns that the roasting and brewing process produces acrylamide which is associated with causing cancer. The reality is that coffee contains a number of potentially valuable components including a host of antioxidants (good chemicals) and after ~1000 studies the World Health Organization’s International Agency for Research on Cancer (IARC)  found that coffee did not pose a risk of cancer.


Should we talk about the various sweetening agents used in your coffee ? As most of us know  you can literally throw a monkey wrench in the works as  adding sugar increases inflammation. If your going for the artificial sweeteners consider reading this publication, “Artificial sweeteners and cancer risk: Results from the NutriNet-Santé population-based cohort study“. The short version, avoid them period.


Plastic and hot water

One of the clear considerations is avoiding getting plastic agents, such as the group of chemicals known as phthalates into your cup of coffee. The keurig containers are all plastic and some adhesive on the aluminum top. On their site nowhere does it say anything about the type of plastics or adhesives, except that we know there K cup is a number 7 plastic.  Keep in mind that you may be using a coffee maker that’s no less toxic. Have you ever brought back a coffee maker and has that less than desirable taste and smell ….could be the plastic in the brew. This group of chemicals has a negative effect on your endocrine system and as the science evolves it’s clearly not appropriate even in small quantities. Need more information see these links for how endocrine disruption can literally trash your health ? See: Endocrine-Disrupting Chemicals (EDCs)

With or Without Caffeine

One of the consensus opinions is that “The consumption of up to 400 mg/day (1-4 cups per day) of caffeine is safe“. As a note. “Each K-Cup® pod contains between 75 and 150 mg of caffeine per 250 ml (8 oz) cup”.

Anyone who drinks caffeinated coffee has experienced the extra energy boost especially, if the consume larger amounts. There are no lack of studies on the impact on our cognition processes . Keep in mind that with excessive intake, which is different for each of us, there may be a number of adverse results such as an elevated blood pressure, pulse rate and for some a decrease in their normal smooth and calm demeanor.

Then we need to consider the method of decaffeinating the beans. Two primary approaches , the chemical based which is much more prevalent and the water extraction, often times referred to as Swiss water processed. The big issues is the chemicals used,  methylene chloride or ethyl acetate.  For a quick take the methylene chloride is recognized as carcinogens….ie. cause cancer.  You’re probably much more familiar than you think. Methylene chloride was commonly found in paint strippers and degreasers. But there’s more….. due to a number of deaths this chemical is no longer sold over the counter as  “The U.S. Environmental Protection Agency’s (EPA) regulations to prohibit the manufacture (including import), processing, and distribution of methylene chloride in all paint removers for consumer use will go into effect after November 22, 2019″. However, it’s not restricted for decaffeination use. What does Keurig say about their beans: “Our roasting partners use different methods to decaffeinate the coffee content in each K-Cup® pod”. Not reassuring given the health considerations and to be fair they do indicate that most of their roasters do use water based decaffination.

For those wanting the rest of the story on the two types of chemical caffeine removal processes, the direct and indirect see this article: how-is-coffee-decaffeinated.

 Coffee with or without a filter

For anyone with elevated cholesterol you may be surprised to know that the oily chemicals found in coffee, diterpenes (cafestol and kahweol), are naturally occurring and have been shown to cause the elevation in both cholesterol and triglycerides . Does the use of a filter make enough of a difference? The jury is out as one study in 2013 titled: “Paper-filtered coffee increases cholesterol and inflammation biomarkers independent of roasting degree: a clinical trial” showed elevations. Where as this study in 1991 showed the opposite,  and another study demonstrated that the difference in the type of filter paper used made a major difference in the amount of the cafestol in the coffee.

Speaking of paper filters, you probably noticed that many are white while some are brown. The difference is the bleaching of the paper.  There are two major ways to bleach, with chlorine which is really bad for the environment or with hydrogen peroxide, which is a better approach and noted as oxygen bleaching on some filter labels. Is there a difference between the cheap and more expensive filters ?  Not surprisingly there is a difference. It has to do with the side of the pores in the paper as well as the amount of “papery” taste from the filter that will wind up in your coffee.

One way to avoid the paper taste is to rinse the filter with water before use.

Flavored coffee:

First let’s get on the same page, when you add artificial agents to your coffee your going down the wrong road as most are artifical. Many of them have a litany of negative effects so let’s just stick to coffee and possibly add some organic milk or milk like option. Did you ever notice the amount of sugar added to the flavored coffees ? Why not just drink a soda ? Take a look at the amount of sugar in Starbucks products at : Starbucks Coffee Company Beverage Nutrition Information  

Engineering Questions:

How clean is your Keurig ? No not the outside or the brushing of the residual grinds. The inside including the tubing and the reservoirs are where we are headed. Do you remember basic microbiology ? If you have heat and water bacteria and mold are very happy and make a home.

How can you really clean your machine, as the interior parts including the tubing and reservoir remain moist ?  Without a full tear down every cycle this would be well in excess of the typical owner’s ability, desire or wanting to void their warranty ? If you can’t fully empty the water holding areas of the unit what can you do to remain safe ?  Some people have suggested running vinegar through the system periodically. That’s unlikely to get you a clean bacteria or mold free machine. 

If your concerned with the environment why are you using the  K cup that can’t be recycled as it’s made of #7 plastic, a composite ?

There are many simple coffee devices from the pour overs to the Chemex and more that make the grade.  Think in terms of Easy to clean, safe materials, reusable and recyclable.


Take Aways:

Use a glass or stainless cup when drinking hot beverages

Using a filter, preferably non-clorine treated (see the brown ones)

Fresh is always best, if possible buy small amounts more frequently

Drinking decaff ? …. Swiss water extraction is the way to go….not the chemical approach

Check if your taking any drug that are affected by caffeinated coffee intake: see

Grind with a burr based grinder for optimal results….. yes you can taste the difference

Avoid the plastic containing coffee machines, there a lot of them

Flavored coffee is not the real deal, avoid

A simple ceramic