Can you have black coffee when fasting for blood work?

In this text, we will answer the question “Can you have black coffee when fasting for blood work?” and we will discuss the theme. In addition, we are going to discuss a bit about the requirements for fasting. 

Can you have black coffee when fasting for blood work?

No, you can not have black coffee when fasting for blood work. Unlike water, drinking coffee can interfere with the results of certain tests. Therefore, its consumption should be avoided, whether pure, with sugar or with sweetener.

Even without the addition of sugar, coffee can interfere with the results of certain tests, changing some biochemical dosages.

However, the food or fasting required will depend on the type of blood test. The healthcare provider ordering the test will tell you if you will need any special preparation.

In some blood tests you will be allowed to eat normally, while in others where fasting is required, you will be warned in advance not to eat or drink anything other than water.

The truth is that any food, if consumed in excess in the days before the exam, will cause you to have a higher level of certain substances in the body, which can interfere with the results.

What is the required fasting time for blood work?

The required fasting time for blood work is the minimum 3 hours and should never go beyond 14 – since at this time the body starts to use reserves, burning fat and protein, which may alter the final result of the tests. It turns out that each person has a different metabolism and today that 12-hour time is not always necessary.

Therefore, generally speaking, you can have breakfast if your exam is at least 3 hours after your meal. For example, breakfast at 7:00 am with an exam at 10:30 am is allowed.

But it’s worth paying attention to confirm with your doctor and your laboratory the necessary fasting time for you. There may be other tests along with the blood test and you don’t know it.

Finally, before any exam, avoid intense physical activity for at least 24 hours and no alcoholic beverages for at least 72 hours (3 days).

What does blood work require fasting?

Blood work that requires fasting are glucose and fats. Since blood glucose and fats can be elevated for several hours after eating, blood glucose, triglycerides, or cholesterol are the most common tests that require fasting.

The analysis of blood iron levels, used to diagnose conditions such as anemia, also requires a 12-hour fast to be performed.

Your doctor may even ask you to avoid alcohol, certain nutritional supplements, or medication before the test. But as a rule you can take them normally.

Why should you not drink black coffee before a blood work?

You should not drink coffee before a blood work mainly because the caffeine in the drink can interfere with your test results.

This is because, in the morning, usually 1 hour after we wake up, our body experiences a spike in Cortisol, which is also responsible for keeping us awake and alert.

The caffeine present in this drink causes the level of this hormone to rise in the body, in addition to influencing the increase in Adrenaline, Noradrenaline and GH, especially in stressful situations.

Also, adding sugar or sweetener to your coffee will likely interfere with the test results. The reason for this is that any food eaten within the estimated period for fasting modifies biochemical dosages (such as blood glucose, for example).

These and other changes can “make up” the results of your exams, therefore, it is not recommended to consume coffee during the fasting period, when it is necessary!

To make sure coffee breaks fast for more specific blood tests, contact your testing laboratory or your trusted physician.

Can you drink black coffee before a cholesterol blood work?

No, you cannot drink coffee, even sugar-free, before a cholesterol blood test. Any food, with the exception of water, when ingested, interferes with the test results because they modify some biochemical dosages.

This is because normally 1 hour after we wake up, our body experiences a spike in cortisol, which is also responsible for keeping us awake and alert.

The caffeine present in this drink causes the level of this hormone to rise in the body, in addition to being boosted in the increase of Adrenaline, Noradrenaline and GH, especially in stressful situations.

These and other changes can “make up” the results of your exams, therefore, it is not recommended to consume coffee during the fasting period, when it is necessary!

Other FAQs about Coffee that you may be interested in.

Can you grind green coffee beans?

Can you have coffee with braces?

Can you make coffee in a tea infuser?

Conclusion

In this text, we answered the question “Can you have black coffee when fasting for blood work?” and we discussed the theme. In addition, we discussed a bit about the requirements for fasting. 

Citations

https://www.goviter.com/blogs/viter-energy-blog/coffee-blood-test

Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.