Does Putting Butter in Your Coffee Increase Brain Function? The Scientific Verdict

October 11, 2025 •

2 min read

According to a 2021 study, a high-fat coffee beverage with MCT oil and ghee provided no additional cognitive benefits over black coffee in healthy adults. This raises a key question: does putting butter in your coffee increase brain function, or is the hype simply anecdotal?

Quick Summary

We explore the evidence on butter coffee's impact on cognitive function, noting that scientific studies find no superior brain boost over regular black coffee, though individual components have separate effects.

Key Points

Scientific Consensus: Research currently does not support the claim that butter coffee uniquely increases brain function compared to regular black coffee.
MCT Oil and Ketones: The potential cognitive benefits likely come from MCT oil, which the body converts into ketones, an alternative fuel for the brain, particularly for those on a ketogenic diet.
Caffeine's Role: Much of the alertness and focus is due to caffeine, a known central nervous system stimulant, rather than the addition of butter.
Increased Satiety: The high-fat content does effectively suppress appetite and increase feelings of fullness, which is a key reason for its popularity among dieters.
Significant Downsides: Regular consumption introduces a high amount of saturated fat and calories, potentially raising cholesterol and causing gastrointestinal distress, especially if replacing a balanced meal.

The Allure of Bulletproof Coffee and The Biohacking Trend

Entrepreneur Dave Asprey popularized 'Bulletproof Coffee,' a beverage combining coffee, grass-fed butter or ghee, and medium-chain triglyceride (MCT) oil, as part of the 'biohacking' trend aimed at optimizing mental and physical performance. It gained popularity for its promise of sustained energy and mental clarity without the crash associated with sugary breakfasts.

The Proposed Mechanisms: How it Allegedly Works

Supporters suggest butter coffee enhances brain function through two main mechanisms:

Slowed Caffeine Absorption: The fats potentially slow down caffeine release for sustained focus.
Ketone Production from MCTs: MCT oil is quickly converted to ketones, an alternative brain fuel, potentially benefiting those on low-carb diets.

What the Science Actually Says

Despite anecdotal claims, scientific evidence for butter coffee's unique brain-boosting effects is limited. A 2021 study found no significant difference in cognitive performance between those who drank Bulletproof Coffee and those who had black coffee, although the high-fat drink did increase fullness. A review of studies from 2010-2023 concluded insufficient evidence supports Bulletproof Coffee's claims regarding cognition, alertness, or energy; any perceived benefits likely stem from caffeine alone.

Risks and Downsides to Consider

Potential health risks of regular butter coffee consumption include:

High Saturated Fat: High saturated fat intake can raise cholesterol in susceptible individuals.
Nutrient Displacement: As a meal replacement, it lacks the balanced nutrients (protein, fiber, vitamins, minerals) found in a traditional breakfast.
Gastrointestinal Distress: High fat content, especially MCT oil, can cause digestive issues like bloating or diarrhea.
Calorie-Dense: Its high-calorie count can contribute to weight gain if not accounted for.

Butter Coffee vs. Black Coffee vs. Balanced Breakfast


Feature	Butter Coffee	Black Coffee	Balanced Breakfast
Calories	Very High (250-450+)	Very Low (0-5)	Moderate (250-500)
Saturated Fat	Very High	Zero	Low to Moderate
Fiber	Zero	Zero	High
Protein	Negligible	Negligible	High
Vitamins/Minerals	Poor Source	Poor Source	Rich Source
Cognitive Effects	Attributed to Caffeine/MCTs; No proven superiority over black coffee	Attributed to Caffeine; Proven to enhance alertness and focus	Sustained energy and brain fuel from complex carbs and nutrients
Satiety	High	Low	High

Conclusion: The Final Verdict

Scientific evidence does not strongly support the claim that butter in coffee uniquely enhances brain function. While individuals report sustained energy, this is likely due to caffeine and potential ketone production from MCT oil, particularly in low-carb dieters. The high fat content does increase fullness, which can help manage appetite. However, these aspects come with notable nutritional drawbacks, including high saturated fat and calorie content, nutrient deficiencies if replacing meals, and potential digestive issues. For most people not on a strict ketogenic diet, the cognitive benefits are probably no greater than regular coffee, and a balanced, nutrient-dense breakfast offers superior overall health benefits.

For further reading on the effects of high-fat beverages on cognition, see this review: Assessing the Validity of Bulletproof Coffee's Claims - MDPI.

Frequently Asked Questions

No, scientific studies have not shown that butter coffee provides a superior cognitive boost over black coffee, indicating that caffeine is the primary driver of alertness in both.

The feeling of sustained energy and focus may come from the combination of caffeine and the fats from MCT oil, which provide a slower, more prolonged energy release.

MCT (Medium-Chain Triglyceride) oil is a type of fat that is easily converted by the liver into ketones, which the brain can use as a quick energy source, especially on a low-carb diet.

While it can fit into a ketogenic or low-carb diet, it is extremely high in calories and saturated fat. It should not replace a nutritious, balanced breakfast rich in fiber, protein, and other vitamins.

Yes, potential side effects include gastrointestinal distress, upset stomach, and potential increases in cholesterol levels due to the high saturated fat content, especially for individuals sensitive to it.

It can aid in weight loss by increasing feelings of fullness and suppressing appetite, which may lead to reduced overall calorie intake. However, it is also very high in calories itself, so consuming it in addition to a normal diet can cause weight gain.

For brain health, focus on a balanced diet rich in omega-3 fatty acids (fatty fish), antioxidants (berries), and healthy unsaturated fats (olive oil, nuts), along with regular physical activity.