Science & Health

Bulletproof Coffee: Debunking The Hot Buttered Hype

Bulletproof Coffee: Debunking the Hot Buttered Hype

People are putting butter in their coffee. And, hey, if you’re just craving a new flavour experience, more power to you. The problem is that Bulletproof Coffee, the company behind the trend, is claiming that drinking a mug of fatty joe every morning instead of eating breakfast is a secret shortcut to weight loss and mental superpowers, and now the butter coffee has developed a cult of highly caffeinated, shiny-lipped adherents. So now we have to talk about it.


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What the hack is Bulletproof Coffee?

Bulletproof Coffee is, essentially, a hot coffee, plus two tablespoons of butter, plus a tablespoon of MCT oil (that’s medium chain triglyceride oil, which we’ll talk more about in a minute). Then you stick it in a blender until it’s all emulsified. Then you drink it.

Depending what level of the Bulletproof Diet you adhere to (yes, there’s a whole diet that goes with this), that is generally your entire breakfast. According to Bulletproof, you should reeeeally be buying its outrageously overpriced “upgraded” coffee beans and its version of MCT oil which it has branded “Brain Octane,” or, y’know, maybe this magical coffee won’t work!

Bulletproof Coffee was started by Silicon Valley investor/entrepreneur Dave Asprey, who calls himself “The Bulletproof Executive”. The lore goes something like, Dave was a big fat guy, and then he turned is obsessive mind to become a “biohacker”, and he hacked his way into health and fitness. Because everything is a hack. One of the key components to reinvention, he claims, was his buttery coffee breakfast, which he was inspired to create this after having some traditional yak-butter tea in Tibet.

OK, that’s all fine. Where things get dodgy is when we get into Dave’s claims for what this coffee does. The most dubious one is that starting your day off like this turns your body into a fat-burning machine. That it promotes healthy weight loss. That it eliminates hunger pangs. But wait, there’s more! He also insists that it’s the secret formula for improving mental focus and brain power. That it’s a way to improve the effectiveness of coffee, making it jitter-free and eliminating spikes and crashes. And also that it’s delicious.

There are a lot of very bold claims to dig into. Some are extrapolated from nuggets of truth. Some are wildly baseless. Let’s start off with a very important lesson we learned from All The President’s Men.

Follow the money

OK, so you’re an entrepreneur and you’ve come up with this idea that adding butter and MCT oil to your coffee is the secret to all kinds of good stuff. You’ve still got a problem: You can’t monetise a three-ingredient recipe. Damn. There’s got to be some way you can get rich off telling people to do this.

Enter the Bulletproof product line. They sell a ton of dubious health products at a significant markup, but let’s focus on the stuff that goes into the coffee.

First up is Bulletproof’s Upgraded Coffee Beans. One of the boldest claims Asprey makes is that most coffee is loaded with “performance-robbing” mycotoxins that “steals your mental edge and actually makes you weak.” This is the least-bulletproof of all of Asprey’s arguments. Mycotoxins are, basically, mould, and it’s true that many of them are bad for you, inflammatory, and maybe even cancer-causing.

Asprey claims that his Upgraded beans undergo a secret, proprietary process that all but eliminates mycotoxins. He also claims that mycotoxins are the reason you coffee is bitter.

This is almost entirely bullshit.

For starters, while mycotoxins can grow on coffee beans, the coffee industry has known about this for decades. This is why wet-processing was developed; a technique employed by nearly every roaster in the world, wherein the beans are washed, and nearly all mycotoxins are eliminated.

This is something that is regulated both internationally and in the US. In fact, one Spanish study found that people who drank four cups of coffee a day (and this is any brand of coffee, regardless of price and quality) had only 2 per cent of what is considered a safe level of mycotoxins.

In other words, you could drink 199 cups of coffee in a day and still be under the safe limit for mycotoxins. Further, mycotoxins are everywhere, including human breast milk, and a lot of the meats Asprey recommends in his own Bulletproof Diet.

There is also absolutely zero evidence to support Asprey’s claims that his coffee has fewer toxins or provides better performance. Also, just what the hell does “performance” mean in the context of coffee? Unclear. What is clear, however, is that Asprey charges more than $US25 per pound of his “upgraded” coffee. To its credit, it is a tasty cup of coffee, but I’ve had cups that were just as tasty, and “performed” just as well, that cost half as much. If you want to learn more about mycotoxins in coffee, this is a very good read.

Then we have the Brain Octane, Bulletproof’s version of MCT oil. Let’s be clear here: It’s just MCT oil. There’s nothing special about it. Bulletproof claims that while other oils have an “unpleasant goat-like smell and taste” Brain Octane tastes like nothing at all, so you can put it in anything! Great, except that any decent MCT oil you buy won’t taste like anything. So what’s the difference, besides the name?

Well, Bulletproof sells 16 ounces of Brain Octane for $US23.50. In contrast, I was able to buy the one-litre bottle of the Now Foods brand (which I’ve found to be quite reliable) at Whole Foods for the same price. Yes, at Whole Foods — the store often dubbed “Whole Paycheck” — it costs half as much. Go online, and you can find the one-litre bottle for $US16, which is roughly one-third the cost of Brain Octane.

Get the picture? I have tried Bulletproof Coffee with their beans and their MCT oil, and I’ve tried it with some coffee I bought at a local café, Now Foods MCT oil, and butter from my nearby natural grocery store. There was no detectable difference.

Bulletproof Coffee: Debunking the Hot Buttered Hype

Large claims court

OK, we’ve tackled the Bulletproof branded products, but let’s dive into some of the other claims.

“I’m programming my body to burn fat for energy all day long!”

There are no peer-reviewed studies that corroborate the idea that eating nothing but fat (and caffeine) in the morning, sets you up for burning body fat. Conversely, the majority of the studies Asprey sites for his diet were done on rats and mice. Some were four decades old. Some used humans, but in incredibly small numbers. One study’s entire sample consisted of two people. One was just on rats with an auto-immune kidney disease.

This is what’s known as confirmation bias. For those unfamiliar with the concept, it’s when you start with a conclusion and then go looking for evidence to support it, generally ignoring evidence that may contradict it. It is the opposite of good science.

You can lose half a kilo a day on this diet.

This may be true, but that doesn’t mean it’s a good thing or that it’s good for you. Hell, I lost 2.7kg in four days by eating nothing but ice cream. And then I gained literally all of that weight back that very weekend. This is the problem with these extreme diets that promise rapid results: They aren’t sustainable. You can lose weight on just about any diet (Paleo, Atkins, South Beach, 4 Hour Body, etc), but the number one reason that extreme diets fail is that they are very hard to stick with over time.

And make no mistake, the Bulletproof Coffee Diet is most definitely extreme. Between the two tablespoons of butter and one tablespoon of MCT oil in your morning coffee, you are consuming 140 per cent of your RDA for saturated fat before you have taken a single bite of real food. As for the rest of the diet, it’s basically a high-fat riff on the Paleo Diet (which is, itself, highly controversial).

Bulletproof recommends that you get 50 to 70 per cent of your daily calorie intake from fat. While nutritional science has definitely come around on fat, it hasn’t come around that much. Saturated fat may no longer be the villain it once was, but that doesn’t mean it should make up more than half of your diet. Most nutritionists, who recommend a balanced diet, would put that number around 25 per cent.

While no one diet is a perfect fit for everyone, some conventional wisdom has stood the test of time. If you want to lose weight and keep it off, increase the amount of calories you burn by becoming more active, and then find a way to reduce the calories you consume until you’re burning a bit more than you consume. Say, 100 more a day. Find a way that feels right to you, so you don’t feel like you’re starving, and so you get all the nutrients you need. The pounds won’t just “melt away,” but if you are much more likely to keep going with it. For a crash-course in fat, read this.

Butter in your coffee is delicious.

Yep. Got to hand it to them here, buttery coffee is indeed pretty damn tasty. And though it sounds strange, it shouldn’t really be so surprising. For starters, it’s butter. Butter makes everything taste better. Duh. Secondly, you don’t think it’s so weird that people put cream in their coffee, right? Well, what is butter but cream that has been churned? When you thoroughly blend it with the hot coffee it does a pretty good job of emulsifying the fat, and the end result looks and tastes much like a latte. But you really notice the fat on your lips after you take a sip. It feels like you put too much lip-gloss on. But still, tasty, yes.

MCT oil as a miracle food.

So, here’s the short and very high-level explanation on MCT oil. Most of the fats in the foods we eat are primarily composed of long chain triglycerides (LCT), but a few foods, such as coconut and palm oils contain higher amounts of medium chain triglycerides (MCTs). Because LCTs are longer, they have to go through more digestive processes before our bodies can use them as energy. Because MCTs are much shorter, they represent more rapidly accessible energy.

This, in theory, means that our bodies use them more like a carb. MCT oil, which is extracted from coconut and palm oils, has been used in hospitals for a long time for patents whose digestive systems aren’t working properly but still need to ingest fats to maintain health (commonly AIDS patients).

There are still very few peer reviewed studies on the effectiveness of MCT oil for weight loss, but there are some, and there are some more that use coconut oil. It would be a stretch to call these conclusions solid, but it appears that MCT oil may contribute to a small amount of fat loss for overweight men. We’re talking 1.8kg over 12 weeks. For women results were even less certain. A lot more research needs to be done before it can be billed as a miracle cure. The best distillation of the research that’s been thus far can be found here.

As far as MCT oil improving brain function, that’s not a call that can be made yet (sorry Bulletproof). There was a study that used MCT oil to treat people with Type 1 Diabetes and another that used it for Alzheimer’s patients, and both studies found that MCT oil helped to repair some cognitive function. BUT (and it’s a big but), we cannot extrapolate the results from subjects with significant cognitive impairment and pretend to know the impact on subjects with normal cognitive function. It would be nice, but that’s just not how biology works.

Is it possible? Yes, it’s possible, but it’s far from proven. Indeed MCT oil is very controversial in the nutritional community.

It delivers longer-lasting caffeine without the spikes and crashes

To me, this is one of Bulletproof’s more interesting claims. I haven’t seen Bulletproof’s explanation for the mechanism for this improved caffeine experience, but I have a guess at how it might work, if it works.

Caffeine is both water and lipid soluble. So, when you put all that fat into the coffee and then blend the bejeezus out of it, it’s possible that some of those lipids would absorb some of that caffeine. Generally speaking, your body digests fats slower than carbs. So it’s possible that these little blobs of fat sort of act like time-release capsules for the caffeine. This is, after all, how pot brownies (made with weed butter) work, and why the effects come on so slowly and last for so long. Or so I’ve read.

In trying it, I did feel like it delivered a somewhat more even come-up, and it didn’t get as jittery as I would have if I just drank a cup of black coffee on an empty stomach and then didn’t eat anything for four hours. That said, I still felt more caffeinated than I wanted to be, and I definitely felt a crash in the afternoon, so that seems like bunk to me. I’d be willing to experiment with this premise further, but not on an empty stomach. Speaking of…

Drink this coffee for breakfast and no hunger pangs ’till lunch

NOPE! Nope nope nope. Nuh-uh, wrong, no way. I tried this, first thing in the morning, with two other friends (one male, one female, both early 30s). We were just getting hungry when we started drinking the coffee. By the time we were finished, we felt a little queasy (see: ingesting 140 per cent of your saturated fat in one go), but our stomachs still felt very empty. Our bodies still wanted food. Actual food.

In the name of science I didn’t let myself eat anything for another four hours, until lunch time. By that time, I was ravenous. My friends broke their fast even earlier. That was the least fun part about this whole thing. It doesn’t matter than you’re getting roughly 450 calories (all from fat) — you need real food. That’s the way it works in nature, and your body knows it.

You might be thinking, “Oh what’s the big deal, so you fast for four hours in the morning…” but no, unless you were eating in your sleep, then you’ll have been fasting for more like 12 hours by the time lunch rolls around. Consider than most nutritionists recommend eating five small meals a day, nicely spread out, because it allows for better nutrient absorption and better processing of the food you consume. This is basically the opposite of that. You will have trouble not binging at lunch, and this kind of behaviour will cause blood sugar spikes and valleys, even if the caffeine distribution is more even. The whole feast and famine thing really throws you for a loop.

It should be noted that one of the lesser-known forms of the Bulletproof Diet (there are three) suggests that you eat something along with you morning coffee. This seems to be a much more reasonable approach. If you’re going to do this crazy fatty coffee thing, at least make yourself some eggs and veggies to go with it, because a cup of Bulletproof Coffee does not provide the nutrients you need to survive. Any of them, except for fat. And it’s got too much of them.

Bottom line

Look, there are some interesting ideas here, but this is, at its core, a fad diet. I asked nutritionist Maren Robinson, CNC, MPH, formerly of the CDC and Harvard School of Public Health, now with Kaiser Permanente in California, what she thought about it. “It may in fact contribute to weight loss, but it’s not a nutrient balanced diet or a long-term lifestyle change,” she said. “To me it represents the American obsession with a quick fix to weight loss.” Exactly.

My biggest problem with the coffee itself is that it’s excessive. Look, if you want to try blending a little butter into your coffee, have at it! Honestly, I don’t think it tastes much different from cream, but hey, maybe it will be your new favourite thing. But jeez, don’t use two tablespoons of butter. And don’t try to pretend it’s a meal. It’s a beverage. Wanna experiment with MCT oil? You don’t need to take the full tablespoon all at once. In fact, you probably shouldn’t, because your body is going to have trouble processing all that oil when you napalm your system with it like that (See the Paul Thomas Anderson movie, There Will Be Poop.)

Bottom line: It’s almost certainly a bad idea. Ultimately, it seems to me that Bulletproof Coffee is a scheme to get you to buy some very expensive magic beans. There are better ways to get healthy, and there are tastier was to drink coffee that don’t involve coating the inside of your blender with butter every morning. Keep it balanced, folks.

Picture: Michael Hession


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