The Best Time To Drink Coffee, According to a Dietitian
Most people drink coffee in the morning, but some people consume it throughout their day, including during work, before exercising, and even as a post-dinner beverage.
While coffee intake is generally linked with a number of health benefits—from reducing the risk of conditions like type 2 diabetes and liver cancer to boosting exercise performance—some people wonder if the timing of consuming caffeine makes a difference for health.
Here’s how drinking coffee at different times of day affects your body and the best times to drink it for weight loss, boosting energy levels, and supporting restful sleep.
Coffee contains caffeine, a central nervous system stimulant that makes you feel more alert and energized. Caffeine can affect your energy levels, as well as your blood sugar, sleep quality, and levels of certain hormones.
Morning
Since coffee packs around 92 milligrams (mg) of caffeine per cup, it can help boost your energy levels and help you feel more awake in the morning. However, some people argue that consuming coffee first thing in the morning may negatively affect your health due to its effect on your blood sugar and certain hormones.
Cortisol
Some people avoid drinking coffee first thing in the morning because they think it negatively affects the stress hormone cortisol. Cortisol plays important roles in regulating immune function, metabolism, inflammation, and stress.
Though cortisol is essential to health, elevated levels of cortisol are detrimental to the body and are linked with medical conditions like high cholesterol, high blood sugar, hypertension (high blood pressure), and excess belly fat.
While some studies have shown that caffeine can temporarily raise cortisol levels in certain populations, such as those under stress, research suggests that drinking caffeinated coffee doesn’t significantly affect the cortisol levels of people who regularly drink coffee.
A study of 148 people found that regular caffeine use did not significantly affect baseline cortisol levels or trigger fluctuations in cortisol levels. However, the study found that caffeine use increased cortisol levels when the participants were exposed to stressful situations. This means that, while you don’t have to worry about caffeinated coffee affecting your cortisol levels in general, you may want to cut back on your caffeine intake if you’re under a lot of stress, such as when you’re sick, are sleep-deprived, or are having a particularly stressful day.
Blood Sugar
Though there’s no convincing evidence that you should delay your morning coffee based on its effect on cortisol, you might want to hold off on your daily cup of joe for better blood sugar control.
Another study of 29 adults found that when the participants drank coffee after a night of disrupted sleep, it negatively affected their glucose tolerance, or how well the body uses and regulates blood sugar. When the sleep-deprived participants consumed black coffee that contained 300 mg of caffeine 30 minutes before drinking a sugary drink, their blood sugar response to the drink significantly increased by around 50%.
This means drinking coffee before a meal, like meals high in sugar, could impair your body’s ability to maintain healthy blood sugar levels, especially after a night of disrupted or little sleep. If you have high blood sugar or sleeping issues, it may be best to have a protein-rich meal before drinking your morning cup of coffee.
Afternoon
Consuming caffeinated drinks, like coffee, could help improve your performance and energy levels at the gym or wherever you exercise, which can help you get a more effective workout. The International Society of Sports Nutrition (ISSN) recommends consuming caffeine products, like coffee, around 60 minutes before workouts for the greatest benefits.
Drinking coffee during the afternoon at school or work can also help you perform better mentally. Caffeine can increase alertness and enhance brain function, which is why so many people reach for a cup of coffee to improve their efficiency and performance during their workday.
However, it’s important to note that drinking coffee in the afternoon, even earlier in the day, can interrupt your sleep pattern, especially if you’re sensitive to caffeine. Some research shows that consuming caffeinated coffee within 6-8.8 hours before bed can disrupt your sleep.
While caffeine tolerance varies, if you’re sensitive to caffeine, it’s best to cut off caffeinated beverages within eight or so hours of your bedtime.
Evening
Because caffeinated coffee increases alertness and keeps you awake, most people sensitive to caffeine avoid drinking coffee in the evening, especially before bed.
That said, your sensitivity to caffeine depends on your genetics. Some people have no issue falling asleep right after consuming coffee, while others experience disrupted sleep even when their last cup of coffee is hours before bedtime.
For those sensitive to caffeine, drinking coffee too close to bedtime could increase the time it takes to fall asleep and reduce total sleep time. This sleep disruption may lead to overconsumption of caffeine the following day to boost energy levels, impairing the next night’s sleep cycle. This dependence on coffee to make up for disrupted sleep is known as the “coffee cycle.”
According to findings from a 2023 review, caffeinated coffee should be consumed at least 8.8 hours before bedtime to minimize caffeine’s negative effects on sleep.
Research findings suggest drinking coffee could help promote fat loss and protect against weight gain.
A study of 1,483 participants with metabolic syndrome found that those who increased their coffee consumption from no coffee or less than 3 cups per month to 1-7 cups of coffee per week had greater reductions in total body fat—including a harmful type of deep belly fat called visceral fat—over three years compared to participants who didn’t increase their intake.
Drinking coffee may also help some people maintain a lower body weight and less body fat, possibly due to coffee’s effect on appetite. A 2017 review found that consuming caffeine 30 minutes to 4 hours before eating reduced calorie intake at meals, which could enhance weight loss and support body weight maintenance.
In addition to reducing energy intake at meals, research suggests that caffeinated beverages, like coffee, may help you burn more calories by slightly increasing your resting metabolic rate, or the calories you burn while at rest. Caffeine has also been shown to boost fat oxidation (the breakdown of fat in the body).
Coffee can be consumed around 60 minutes before workouts to help boost performance, energy output, and fat-burning during physical activity. This can create a greater calorie deficit to encourage weight loss.
Still, don’t depend on coffee to reach your body composition goals. Choosing the right foods, such as those high in satiating nutrients like protein and fiber, and reducing your overall calorie intake are much more important for weight loss and maintaining a healthy body weight.
No solid scientific evidence indicates a “best time” to drink coffee.
However, since drinking coffee too late in the day, from 6-8.8 hours before bedtime, could disrupt sleep, it’s generally best for most people to limit their coffee intake from the morning to early or midafternoon.
For people with high blood sugar levels and those under stress, it may be best to delay your morning coffee until after you’ve had a nutritious, protein-rich meal, which can help balance blood sugar and cortisol levels.
People who want to use caffeine as a natural exercise enhancer should aim to consume coffee around 60 minutes before their workout for the best results.
It’s recommended to keep your caffeine intake under 400 mg per day, which equates to the amount found in about four cups of coffee. Exceeding this limit could result in symptoms like irritability, rapid heart rate, insomnia, jitteriness, and nausea.
People who are pregnant should limit caffeine to 200 mg per day or less. Consuming higher amounts may increase the risk of miscarriage and other complications, such as low birth weight.
If you consume more than four cups of coffee daily, you’re likely overdoing the caffeine. Here are some ideas:
- Swap out a few cups of regular coffee with decaf coffee
- Try a lower-caffeine alternative like green tea, which contains only 29.4 mg of caffeine per cup
- Try herbal teas, like hibiscus tea, which are naturally caffeine-free
If you find that drinking coffee later in the day or at night causes sleep disturbances, try pushing back your last cup of coffee by a few hours to see if it helps improve your sleep quality.
Coffee intake is linked to several health benefits, but choosing the right time to drink coffee is important.
While enjoying coffee in the morning and afternoon could boost energy levels, cognitive performance, and workout efficiency, consuming coffee too late in the day may negatively affect sleep.
Plus, drinking coffee early in the morning may not be the best idea for people with elevated blood sugar levels or who are under stress.