A few weeks ago, my roommate and I found ourselves chatting alongside two steaming cups of freshly brewed coffee. A great start to my day, if you ask me.
This morning, my refusal of the milk she added to her coffee sparked a conversation that drifted into old wives’ tales. She mentioned that adding milk to coffee could make the caffeine effect last longer and reduce the inevitable crash.
I was in no place to doubt her, after all, it was finals, and I needed all the caffeine I could get. I usually take my coffee black, but this morning I decided to join her in the splash zone.
Later that day, I thought about her claim, wondering if there was any truth to it. Adding fat to coffee is a trend that has persisted in recent years. From butter coffee to Starbucks’ Oleato, an olive oil espresso drink, introduced in 2023, there seems to be a clear market for this beverage. To me, coffee seems like no place for butter or olive oil. But if we take milk in our coffee, then maybe there is some logic to adding butter?
Butter coffee is claimed by users to suppress hunger and enable individuals to lose weight by eating less. Bulletproof coffee takes this trend one step further. This is a type of coffee drink that includes both butter and medium-chain triglycerides (MCTs). MCTs are a type of fat that naturally occur in coconut oil, grass fed butter, whole milk, and avocados, to name a few.
Once consumed, MCTs are rapidly absorbed into the bloodstream and are carried to the liver where they are converted into ketones especially if carbohydrate intake is low. Ketones are compounds that are made by your body when it uses fat instead of carbs for energy. They can be used as a fuel source for brain cells, supporting energy production.
The Bulletproof coffee company also sells and recommends using their C8 MCT oil in coffee. The sole active ingredient in this oil is caprylic acid. Caprylic acid is a naturally occurring fatty acid found in coconuts. Bulletproof coffee claims that caprylic acid turns into ketones within minutes. However, upon a closer look, the research is not conclusive. To date, there exists only theoretical research to prove its efficacy.
Since butter coffee contains a large amount of fat (27g in one serving), drinking the beverage has been linked to greater feelings of satiation. Proponents of Bulletproof coffee claim that adding MCT oil to your coffee has numerous health benefits. Weight loss, increased energy, athletic endurance, gut health, and heart health have all been cited. While adding MCTs into a reduced-calorie diet may increase these feelings, researchers claim that other dietary changes must be made to promote prolonged and continued weight loss.
Purposefully adding non-milk fat to coffee is intended to make the morning beverage a breakfast replacement. This is a trend that has been mimicked by individuals engaging in the new Oat-zempic fad. Each of these weight-loss trends has the potential to encourage disordered eating. Furthermore, they may have greater overall health impacts due to dropping weight quickly and not getting enough essential nutrients.
It is important to proceed with caution.
There is a lack of evidence for the benefits of adding fat to coffee. A 2023 review led by David M. Goldman titled, “Assessing the Validity of Bulletproof Coffee’s Claims” suggests that Bulletproof coffee may not be so bulletproof.
Goldman and his team sought to scrutinize the existing literature aimed at evaluating the health benefits of Bulletproof coffee. The authors were unable to find any indication of significant improvements in cognition, alertness, or energy levels among drinkers of Bulletproof coffee - compared to regular coffee drinkers. While they did encounter findings suggesting that Bulletproof coffee curbs hunger through increasing satiety and fat oxidation, Goldman attributes these findings to users consuming more calories from the Bulletproof coffee.
Products such as Bulletproof coffee must be subjected to scientific scrutiny. No matter how compelling a social media influencer’s anecdote may sound, it is not evidence! As for the role of milk in prolonging caffeination - there is no evidence to support that either. So, for now, have your cup of coffee with it or without. Let your taste buds decide.
Eva Kellner is a recent graduate from the Faculty of Arts and Science, with a major in Environment. Her research interests include urban green spaces, urban agriculture, and outdoor community spaces - all as promoters of climate resilience among city-dwellers.
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