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Caffeine is one of the most popular beverages worldwide, usually consumed as coffee. Some consider it a drug, but it’s merely a stimulant that can be harmless when consumed in moderation.
For those on the keto diet you may be asking yourself – does caffeine affect ketosis and fat loss? Many are still confused as to whether it helps raise your blood ketones or whether it can kick you out of ketosis.
We’ll explore how caffeine works in your body, as well as its benefits and any potential downsides for those on the keto diet!
How Caffeine Works
Caffeine is a psychoactive drug that stimulates the central nervous system. It’s different from cocaine and other drugs that work by binding to the dopamine transporter. Dopamine is a neurotransmitter that makes us perceive pleasure, excitement, and reward.
On the other hand, caffeine works by blocking adenosine, another neurotransmitter that causes relaxation and sleepiness. When caffeine binds to its receptors, we tend to be more awake and alert.
Caffeine occurs naturally in coffee, tea, chocolate, kola nuts, and other plant foods. The average American adult consumes about 4 mg of caffeine per kg of bodyweight, which is 270 mg for someone who weighs 150 pounds. Still, many get much more than the average US adult, especially those who drink several cups a day.
Does Caffeine Affect Ketosis?
Emerging studies suggest that caffeine may help boost ketone levels when consumed in moderate amounts. In a small study of 10 healthy adults, consuming breakfast with caffeine dosages of 2.5 mg per kg body weight and 5.0 mg per kg body weight increased blood ketone levels by 88% and 116%, respectively, compared to having breakfast without caffeine.
The increase occurred when caffeine was included with a breakfast with 85 grams, meaning this is greater in people who follow the low-carb ketogenic diet plan.
If your concern is the possibility of caffeine kicking you out of ketosis, then let’s take a look at the glucose levels of caffeine. Research suggests that caffeine has negative effects on your blood sugar levels and can even get in the way of ketosis, which is in contrast with the other study mentioned.
But if you’re on keto, that means you’re not eating a lot of carbs, and your blood sugar levels should be lower than most. This means consuming caffeine shouldn’t have a detrimental effect unless your body hasn’t fully adapted to ketosis yet.
Everyone who follows the keto diet will want to keep their caffeine intake to moderate levels, with a maximum of one or two cups a day. Excessive intakes may not only kick you out of ketosis, but also lead to a higher risk of type 2 diabetes.
Another way to enjoy your cup of joe on keto is to avoid sugar and cream since these are the dangerous ingredients that can knock you out of ketosis. A cup of black coffee on its own has 0 to 1 grams of carb, so it’s ideal to keep you focused and alert.
Does Caffeine Affect Fat Loss?
Caffeine also promotes fat burning by helping you suppress your appetite. It has been proven by many studies that caffeine can boost the metabolic rate by up to 13%, depending on the dosage and the person.
In fact, one study showed lean adults consuming 100 mg of caffeine every two hours for a total of 600 mg within 12 hours burned an average of 150 extra calories, whereas formerly obese adults burned an extra 79 calories.
Caffeine is one of the few substances that can help you mobilize fats from your fat tissues and increase metabolism. This is one reason why it is included in most fat-burning supplements. It affects the nervous system by sending direct signals to the fat cells, telling them to break down fat.
One major caveat is, you may become tolerant to the fat loss effects of caffeine. It may only boost your metabolic rate and increase fat burning in the short term and suddenly stop after a while. But even if coffee doesn’t make you expend more calories in the long term, there is still a possibility that it blunts appetite and helps you eat less.
A contradicting study shows that caffeine can make you gain weight because it contains cortisol. Elevated cortisol suppresses immunity, enhances muscle breakdown linking to abdominal fat.
Caffeine and Hunger
As mentioned, caffeine does a lot to combat your hunger pains. Caffeine can serve as a supplement to ketosis in suppressing your hunger dramatically. It can be a powerful way to make sticking to a restrictive diet plan easier.
Coffee, for instance, has phytochemical compounds called chlorogenic acids which are responsible for controlling your hunger. These acids can also be found in apples, pears, artichokes, strawberries, pineapple, sunflower and blueberries.
However, there are also studies that show no association between caffeine intake and appetite suppression, concluding that it is not an effective appetite suppressant.
Other Effects of Caffeine
Caffeine has other benefits for you! Here are some of them
- Increased physical performance. Caffeine helps your body enhance its response to strength and endurance training.
- Caffeine protects the liver. Caffeine, specifically in the form of coffee, can help protect your liver against cirrhosis and fatty liver.
- Caffeine improves your mood. Many studies have proven how caffeine has positive effects on mood, alertness, and levels of fatigue. For instance, in one study of mentally fatigued adults, consuming caffeine was found to increase their endurance performance by 14% and improve their mood.
However, caffeine also has some downsides. Some of these may not apply to you, especially if the amount of caffeine you consume is moderate.
- Dependence. Caffeine on a regular basis can lead to dependence. Withdrawal symptoms like headache and nausea may occur in heavy caffeine drinkers after going several hours without caffeine.
- Insomnia. A stimulated nervous system means coffee blocks the release of brain chemicals that cause relaxation, interfering with sleep in many people, especially when consumed later in the day. This happens because its effects can remain in our system anywhere from 1.5 to 9 hours, with an average of 5 hours.
- Anxiety. Ingesting a modest dose of caffeine increases the levels of stress hormones cortisol and epinephrine. Keeping cortisol levels within the normal range is important for good health and to prevent weight gain. Research has shown that elevated cortisol levels may increase appetite, food intake, and fat storage around the abdomen.
- Increased risk of heart disease. A study of more than 2000 people found that high caffeinated coffee consumption was linked to increased risk of a heart attack only in those with the CYP1A2 genotype, who are predisposed to being “slow” caffeine metabolizers.
Is Caffeine Good for Ketosis?
We have talked about how caffeine can do wonderful things to your body when you’re on the keto diet as it helps increase your ketone levels. It can also make losing weight quicker since caffeine suppresses your appetite.
Caffeine, when consumed moderately, can have other benefits like mood improvement and enhanced liver health. But it also has some downsides, so slow down on that venti caramel macchiato! And remember to make sure your caffeine is not being consumed with any carbs that don’t fit your macros.
As long as caffeine intake doesn’t go too much beyond the recommended level on the keto diet, then it should be safe for you. The key is taking an honest look at how caffeine affects you, which may include testing blood sugar and experimenting with how you sleep and perform at various doses.
If you decide caffeine is not for you, check out other drinks you can have on the keto diet!