咖啡因會在您的系統中停留多久?

Caffeine is a fast-acting stimulant that acts on the central nervous system. It can increase your blood pressure and heart rate, boost your energy, and improve your overall mood.

However, caffeine may still be present in your system after its effects wear off.

How long does this last? The answer depends on a variety of factors.

how long do symptoms last

According to the American Academy of Sleep Medicine, caffeine has a half-life of up to 5 hours. Half-life is the time it takes for the amount of a substance to reduce to half of its original amount.

So if you take 10 milligrams (mg) of caffeine, 5 hours later you still have 5 mg of caffeine in your body.

The effects of caffeine peak 30 to 60 minutes after drinking. This is the time when you are most likely to experience the "jitter" effects of caffeine.

You may also urinate more due to the amount of fluid you consume and the mild diuretic effects of caffeine.

The other half of your caffeine intake lasts for more than 5 hours.

People who are sensitive to caffeine may feel symptoms for hours or even days after drinking it.

Because of caffeine's long-term effects, the American Academy of Sleep Medicine recommends that you avoid caffeine at least six hours before bed. So if you go to bed at 10pm, you should have your last round of caffeine by 4:00pm.

What foods and drinks contain caffeine?

Caffeine is a natural substance found in a variety of plants, including coffee, cocoa beans, and tea leaves.

Artificial forms of caffeine are often added to sodas and energy drinks.

Within six hours of expected bedtime, try to avoid these foods and drinks that often contain caffeine:

  • black tea and green tea
  • Coffee and espresso drinks
  • chocolate
  • energy drink
  • soft drinks
  • Certain over-the-counter medications that contain caffeine, such as Excedrin

Decaf coffee contains small amounts of caffeine, so you should also avoid decaf if you are sensitive to the effects of caffeine.

Caffeine and breastfeeding

For years, experts have advised women to be careful when consuming caffeine during pregnancy. This is due to the risk of miscarriage or birth defects.

While these effects are no longer relevant after birth, there are still some considerations to consider if you plan to consume caffeine while breastfeeding.

Caffeine can be transferred to your baby through breast milk. It is recommended to limit caffeine intake to two cups of coffee per day while breastfeeding.

If you eat other caffeinated foods throughout the day, such as soda or chocolate, you may need to cut back on your coffee and other high-caffeine foods.

Consuming more than 200 milligrams of caffeine per day may have unintended consequences for your baby. They may have trouble sleeping and may become fussy.

Some mothers also notice colic and nervousness in babies exposed to caffeine. Although these are not considered long-term problems, these symptoms may cause discomfort to your baby.

The key to ensuring your baby isn't affected by caffeine is to plan your intake wisely.

According to the Australian Breastfeeding Association, if you breastfeed, your baby can consume about 1% of caffeine.

Peaks are reached about an hour after ingesting caffeine. The best time to breastfeed your baby is before drinking caffeinated beverages or within the first hour of consuming caffeine.

In addition, since the half-life of caffeine in breast milk is approximately 4 hours, it is also recommended to breastfeed 4 hours after ingesting caffeine.

caffeine withdrawal

If you are a habitual caffeine drinker, you may experience withdrawal symptoms if you stop taking it.

According to the American Heart Association, you may experience withdrawal symptoms 12 to 24 hours after your last caffeinated meal. These symptoms may include:

  • Headache (most common symptom)
  • frustrated
  • anxiety
  • sleepiness and fatigue

Caffeine withdrawal symptoms tend to disappear within 48 hours. However, if you're used to eating large amounts, quitting suddenly may make your withdrawal symptoms worse.

The best way to quit caffeine is to reduce your daily intake.

You can simply reduce the number of caffeinated products you consume, or you can replace certain items. For example, you could trade your daily cup of coffee for green tea.

How much caffeine does coffee and tea contain?

The amount of caffeine in a cup of coffee or tea is affected by many factors, such as brewing technique, the type of coffee beans or tea leaves, and how the beans or tea leaves are processed.

Caffeine content in beverages (mg)

  • 8 ounces coffee (95–165)
  • 1 ounce espresso (47–64)
  • 8 ounce cups decaf coffee (2–5)
  • 8 ounce cup black tea (25–48)
  • 8 ounce cup green tea (25–29)

A cup of coffee contains more caffeine than a shot of espresso. This means that a cappuccino with 1 ounce of espresso contains less caffeine than an 8-ounce cup of coffee.

generalize

Caffeine is just one way to increase alertness and combat drowsiness. Due to possible side effects, you may consider limiting your daily intake to 300 mg. This is roughly equivalent to 3 small cups of regular roasted coffee.

It's also important to consider other ways to naturally boost energy levels without caffeine. Please consider the following options to assist:

  • Drink more water.
  • Get at least 7 hours of sleep every night.
  • If possible, avoid daytime naps.
  • Eat more plant-based foods, which may help provide energy without crashing from processed foods.
  • Exercise every day, but not too close to bedtime.

If you often feel tired, talk to your doctor. You may have an undiagnosed sleep disorder.

Certain underlying medical conditions, such as depression, can also affect your energy levels.

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