My patients often ask me, “Can you drink coffee while fasting?”
My response is, “It depends. Why are you fasting?”
Fasting can mean many different things, so before I explore whether you can drink coffee while fasting, let’s define “fasting.”
Types of Fasting
Fasting means not eating for a period of time. This abstinence can also include drinking, depending on the type of fasting you’re partaking in.
For example, the Jewish faith defines fasting (such as for Yom Kippur) as going without food and drink (including water). When my Jewish patients schedule a fasting blood test, I need to remind them that they can drink water. It’s harder to draw blood from a dehydrated patient.
For medical purposes, such as blood draws, we at Banner Peak Health define fasting as abstaining from food for at least 12 hours, but drinking plenty of water is encouraged. This is similar to intermittent fasting, which many people practice as a weight loss method.
Drinking Coffee During Intermittent Fasting
When drinking coffee during an intermittent fast, the devil is in the details. In other words, it depends on what you add to your coffee.
Black coffee is fine since it only contains two to five calories per cup. However, once you add cream and sugar, the calories increase quickly:
- One teaspoon of sugar = 16 calories
- One pump of sweetened creamer = 10–20 calories
- Two teaspoons of whipped cream = 73 calories
- Two teaspoons of half & half = 40 calories
- Two tablespoons of non-dairy creamer = 20 calories
- Two tablespoons of oat milk = 15 calories
Benefits of Drinking Coffee During a Fast
It’s true — drinking coffee can be beneficial while fasting.
Coffee is a mild appetite suppressant, meaning it can fight hunger. It also increases alertness and combats caffeine-withdrawal headaches.
However, if a lack of caffeine causes headaches, you may want to consider why you need so much of it in the first place (e.g., are you getting enough sleep?).
How Coffee Affects Your Body While Fasting
Coffee consumption impacts your hormone levels:
- Increases dopamine: improves focus
- Increases serotonin: can stabilize mood
- Increases cortisol: can compound and lead to excess stress
- Increases adrenaline: when excessive, it can lead to issues with heart rate and anxiety
Today’s Takeaways
The question “Can you drink coffee while fasting?” has no simple answer. It depends on why you’re fasting and what you like to put in your coffee.
Ultimately, if your fasting allows for drinking and your coffee doesn’t contain added cream, milk (dairy or plant), or sugar, enjoy it.
If you’re preparing for a blood draw, skip the Frappuccino for now.
