Fatty Coffee Experiments

Fatty Coffee strategy I use when I am following a particular fasting method that I refer to as Fat Fasting. My main goal with fat is improving cognitive function during the fasting window. Click to learn more about Fat Fasting.

The Perfect Keto Coffee is the exact replication of what I have been drinking for the last couple years when trying to fat fast. It contains a low 60mg of caffeine and around 90 calories from MCTs and no dairy!

Taste is another reason why I really like this product. It makes for a much better morning treat than just putting oil in black coffee. Mocha is my favorite flavor and French Vanilla isnt bad either!

What’s in this guide:

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Yes, I earn commission for the products I recommend. I also do not recommend any product that I don’t think is superior and that I use myself. If that’s the case, why not make a little dough get you a discount??

What is Fatty Coffee?

Fatty coffee is, as it sounds, adding different types of fat to your morning brew.  Fatty coffee has become increasingly popular among not only Ketogenic Dieters but also high functioning individuals who are looking to reap the benefits of improved brain performance that can accompany fatty coffee consumption.

While Fatty Coffee is popular, I think that most people are doing it wrong. Many people who are drinking fatty coffee are using a combination of MCT Oil, butter, coconut oil, and heavy whipping cream.  While this can make for an extremely delicious morning brew, here are a few reasons why this approach may not be the most optimal.

1.       High Calories

Depending on how you make your fatty coffee, adding in MCT Oil, butter, coconut oil and the occasional splash of heavy whipping cream can equal a pretty hefty dose of calories with your morning coffee (between 250-500 depending).  While for some this high caloric intake may lead to more fullness, for most it will lead to an overconsumption of calories throughout the day

2.       Dairy Consumption

Did you know that nearly 75% of the world’s population does not possess the necessary enzymes required to breakdown and digest dairy?  In fact, the overconsumption of dairy can be one of the primary reasons why we many people do not see as much progress as they would like to on a Ketogenic Diet.  Dairy contains a sugar, lactose, which is not only not digested well by the body but can also promote inflammation, something that we really need to avoid if we are trying to optimize weight loss or more importantly our health.  Heavy cream and butter both contain lactose.  Many fatty coffee drinkers may elect to swap butter for Ghee butter, which does contain a much lower amount of lactose but nonetheless can be troublesome to individuals who are particularly sensitive to this sugar.

3.       Breaking a Fast

Many people drinking fatty coffee on a Ketogenic Diet tend to consume it during their fasting window.  This is referred to “Fat Fasting”, which is much different from traditional fasting but can be used for its own benefits. 

While it is true that not everyone considers fat fasting to be a form of fasting, if we consider fasting as any period of time when we are not stimulating an increase in blood glucose or insulin, then fat fasting may fall in the fasting category since fat has been shown to not elicit a blood glucose response….in the right amount.

If fat is consumed in high enough amount, as it is traditionally with fatty coffee, then it is possible to elicit a response in blood sugar and insulin, thus breaking the fast.

A Better Way to Fatty Coffee

The question is how to achieve the benefits of fatty coffee without having to deal with the negatives of fatty coffee.  The answer is in how we make it!

Correct Fatty Coffee.jpg

Typically, the goal of fatty coffee is to improve our cognitive focus, energy, and promote fullness to help extend a fast.  To achieve this, you will be hard pressed to find a better ingredient to add to your coffee than MCT Oil.  MCT Oil, as most of you know, is a unique fat that is more rapidly digested which can lead to the production of ketones.  Having elevated ketones can provide just the benefits we are looking for with fatty coffee.

Additionally, a half serving to a full serving of MCT Oil is only 60 to 120 calories.  This is important because when fat is consumed in a lower calorie amount like this, it can likely allow us to stay in a fasted state which can lead to an even more robust increase in ketones and provide the benefits you are looking for with fatty coffee!

The take home message is if you want to reap the full benefits of fatty coffee, don’t overdo it by adding in extra fat calories or dairy.  Make it simple and stick to coffee and MCTs and watch out, you may find that your morning productivity skyrockets!

Self Experimentation

Trail #1: PKC1

Question: What impact does Perfect Keto Coffee have on blood glucose and ketone levels?

General Goal: Figure out an estimated ketone and blood glucose response to this product.

Unique Goal: Figure out if Perfect Keto Coffee can be an effective way to increase Ketone levels during “Fat Fasting” with the hope of stimulating better brain function.

Subjects- 1 (Myself)


Baseline ketones and glucose were tested in the morning 4 hours after waking up, prior to any food consumption.

Perfect Keto Coffee was administered with 1 cup of warm water.  Product was drank in under 2 minutes. Subject stayed relatively inactive during the test.  Ketones and BG were tested every 30 minutes.


Fat Coffee Experiment Data.png

Experiment Summary:

Ketones did increase in the first 30 minutes and settled back to baseline over the course of the 2 hours.  Here are two possible explanation:

  1. Longer time fasting can lead to more ketone production

  2. MCTs were rapidly converted to ketones

Since a longer time fasting can also lead to great utilization of ketones (which would lower ketones), I theorize that MCTs led to the increase in ketones and I suspect this may have happened in a greater fashion since they were taken in a fasted state.

I was expecting to see an increase in blood glucose from the caffeine but did not. This could be because of 4 possible factors:

  1. Longer time fasted=higher ketones=lower/stable blood glucose

  2. MCT stimulated increase in ketones=lower/stable blood glucose

  3. Caffeine was not high enough to stimulate a blood glucose response

  4. MCTs did something else to mitigate an increase in blood glucose


Perfect Keto Coffee leads to a small but significant increase in ketone levels when taken in a fasted state which could make them a great option for improving energy and brain function.

Fat Fasting.jpg

To learn more about Fatty Coffee, check out Perfect Keto’s website!

Christopher Irvin