Can You Drink Coffee On a Keto Diet?
Coffee is one of the most popular drinks in the world , coming only after water and tea in popularity, respectively. Its widespread consumption is understandable, it contains an appreciable amount of caffeine, the central nervous system stimulant that helps to keep most of the world awake in the morning. Although relying on stimulants to work and function is likely not a sustainable habit, caffeine has been shown in several studies to also improve cognitive functions (such as working memory and the ability to focus) , increase physical power output (including in resistance training) [3–8], and even to help burn fat . Thus, it offers many benefits in addition to keeping individuals awake. But can you drink coffee on a keto diet? Let’s find out.
First, How exactly does caffeine work?
It works in the brain primarily by acting as an antagonist to adenosine receptors . Adenosine is a compound that accrues in the brain over the day, especially after strenuous mental or physical work. Once it binds to its receptor (the A1 receptor), it induces feeling of relaxation and tiredness.
We often metabolize (break down) most of the adenosine that accumulated throughout the day during our sleep, however, there may still be some adenosine binding during the morning, inducing those feelings of tiredness. Caffeine counteracts this action by binding to the adenosine receptor and preventing its activation. Caffeine also binds to another receptor known as the A2A, which release dopamine, and is what gives everyone that stimulatory feeling .
However, most people are not consuming pure caffeine or caffeine pills, they’re consuming a drink that contains caffeine.
Can you drink coffee on a Keto Diet?
One may wonder whether coffee is a safe drink for someone on the keto diet. Luckily, coffee has a myriad of health benefits, and contains no calories and no carbohydrates. Thus, it cannot directly interfere with ketosis via its nutritional content. In short, yes, You can drink coffee on a keto diet.
However, caffeine has been shown to slightly increase blood glucose levels by interfering with the effects of insulin in the blood [12–14]. Although, this antagonistic action by caffeine may also be countered by another compound found in coffee that increases insulin sensitivity, chlorogenic acid [15,16]. Chlorogenic acid is a naturally occurring compound found in many plants and has shown promise in mechanistic studies as an insulin sensitizer. It is believed to primarily improve glucose metabolism by blocking the uptake of carbohydrates in the small intestine [17,18].
Caffeine further can increase the propensity to store energy as glycogen in individuals who are glycogen depleted but reduces the amount of storage in individuals who are sedentary and have existing glycogen stores .
Although people on a ketogenic diet will not have to worry much about coffee interfering with ketosis, this does not mean that consuming coffee doesn’t have any drawbacks. Coffee, or more specifically, caffeine can increase blood pressure [20–22], the intensity of headaches , acid reflux , and increase the frequency of bowel movements . The last one is particularly prominent because it is caused by caffeine’s effect on the central nervous system and effect on the intestinal tract contractions , but also by the contents of coffee which are metabolized by gut bacteria . So even though you can drink coffee on a keto diet, it may be worth adjusting intake based on needs and tolerance.
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