Submitted By Amy Sercel MS RD CD
Edited By Marcia Bristow MS RDN CSSD CD
You can spot a fad diet by the number of unique products or supplements you need to buy to follow the diet as “completely” as possible. The ketogenic diet is arguably the most popular fad diet right now. You can read more about it in our earlier blog post. In short, the ketogenic diet is a very high-fat diet that involves eating no more than about 3 servings of carbohydrate-rich foods per day. This shifts your body away from burning carbohydrates for fuel, and instead forces your body to convert fats into a compound called ketones that your cells can use for fuel instead of carbohydrates.
Right now, there is no shortage of foods, supplements, and other products you can buy to help “push you into ketosis,” prevent digestive distress, or help you get through the “keto flu” more quickly. One product you may have heard of is called Bulletproof Coffee.
Bulletproof Coffee is freshly brewed coffee (ideally made in a French press) blended with about two tablespoons of medium chain triglyceride (MCT) oil and 1-2 tablespoons of butter or ghee.1 Altogether, this comes to about 500 calories and 38 grams of saturated fat.2 For comparison, consider that a person who eats 2,000 calories per day is recommended to get no more than 22 grams of saturated fat in one day.
People have been lightening their coffee and tea with butter for hundreds of years, specifically people living in Nepal, India, Ethiopia, Vietnam, and Singapore. In Ayurvedic cultures, butter tea is thought to “improve mental alertness and cognitive capacity.”3 Fortifying coffee and tea with butter may also provide additional fuel required for life in inclement environments or at high altitudes that naturally increase metabolic rate.
In Western culture, butter coffee has taken off due to its compatibility with the ketogenic diet. According to the website, Bulletproof products are intended to enhance cognitive and physical performance. The makers of Bulletproof Coffee argue that adding grass-fed butter to your coffee will provide you with “high-quality fats that help keep you full and fueled.” Their “Brain Octane Oil” contains MCTs derived from coconut oil. According to the website, this is more effective than regular coconut oil at pushing your body into ketosis. You can buy a kit that contains 12 ounces of coffee, a bottle of MCT oil, and a bottle of grass-fed ghee for about $50 to get started.1
The problem is there isn’t any significant evidence proving that supplementing with MCT oil or following the ketogenic diet are more effective for promoting long-term health. The ketogenic diet was originally intended as a treatment for epilepsy. Studies have shown that up to 50% of these people following the ketogenic diet end up with elevated triglycerides and LDL cholesterol (the “bad” kind), increasing the risk of heart disease.4 Other studies suggest that high-fat diets might promote tumor growth, and diets high in saturated fat promote the storage of fat around your organs.5 On the other hand, diets higher in unsaturated fat tend to decrease your risk of heart disease. Diets that contain carbohydrates from whole grains, fruits, and vegetables have been shown to decrease inflammation compared to high-fat diets, and increase satiety.5 In contrast, high-fat diets increase satiety but also increase inflammation.
Many people recommend switching to MCT oil instead of other types of fats to promote weight loss, claiming that it helps promote satiety by increasing ketone formation. This claim is also not proven. One study showed that people supplementing with MCT oil only lost 0.5 kg more over 10 weeks than people on a regular weight loss diet.6 Half a kilogram (about 1 pound) could be attributed to differences in hydration status and does not indicate more success with long-term weight loss.
All in all, Bulletproof Coffee aims to capitalize on a fad diet without any evidence that it will do anything besides keep you in ketosis. While this might promote weight loss in the short term, there are no studies showing the ketogenic diet is any more effective for weight loss after about 1 year. You may be putting yourself at risk for developing heart disease, and also risk nutrient deficiencies by cutting out food groups rich in vitamins, minerals, antioxidants, and fiber. At the very least, you risk wasting money on a fad that is unlikely to make your life better in the long run.
- Official Bulletproof Coffee Recipe – With Video. https://www.bulletproof.com/blogs/recipes/official-bulletproof-coffee/. Accessed May 27, 2019.
- Can butter coffee jump-start your morning? – Nutrition Action. https://www.nutritionaction.com/daily/brain-health/can-butter-coffee-jump-start-your-morning/. Accessed May 27, 2019.
- Tradition Turned Trendy: Exploring the Origins of Butter Beverages – Food & Nutrition Magazine. https://foodandnutrition.org/january-february-2015/tradition-turned-trendy-exploring-origins-butter-beverages/. Accessed May 27, 2019.
- CPE Monthly: The Ketogenic Diet for Epilepsy – Today’s Dietitian Magazine. https://www.todaysdietitian.com/newarchives/0516p46.shtml. Accessed May 27, 2019.
- Dietary fat: From foe to friend? | Science. https://science.sciencemag.org/content/362/6416/764. Accessed May 23, 2019.
- Mumme K, Stonehouse W. Effects of Medium-Chain Triglycerides on Weight Loss and Body Composition: A Meta-Analysis of Randomized Controlled Trials. J Acad Nutr Diet. 2015;115(2):249-263. doi:10.1016/j.jand.2014.10.022