I will tell you about the 5 types of people who should never drink coffee. Most Koreans love coffee, but there are people who can be fatal to their health if they drink it. If you know this, please stay away from coffee for your health if you are one of them. I'll tell you right away.

Types of people who should not drink coffee

Coffee is rich in antioxidants, which have health benefits. Coffee is rich in polyphenols that eliminate harmful oxygen, the culprit of aging, and some argue that it has a stronger antioxidant effect than vitamin C and vitamin E.
 
However, there are a lot of mixed opinions about whether coffee is good or bad for your body. It is because of caffeine. Coffee is not good for everyone. Caffeine in coffee often plays a harmful role.

1. People with GERD

The first group of people who are harmful to coffee are those with GERD. Caffeine in coffee stimulates acid secretion and affects the lower esophageal sphincter to relax, which can worsen GERD symptoms. People who experience heartburn frequently due to excess stomach acid should also avoid coffee.
 
Especially, a cup of coffee after a meal as a palate cleanser can be more stimulating when there is food in the stomach, so it is better not to drink it. Also, green tea and black tea containing caffeine are not good. It is best to drink herbal tea or not drink any beverages if possible.

2. People with Anemia

The second group is people with anemia. This is because caffeine in coffee interferes with iron absorption in the body. Several studies have already reported that beverages containing caffeine, including coffee, reduce iron absorption.
 
In fact, a domestic research team has reported that drinking a lot of coffee lowers the level of a component called ferritin in our blood. Ferritin is a protein that plays a very important role in the process of supplying iron to our body. Low ferritin means that the amount of iron stored in our body is also low.

3. People with Diabetes

The third group is people with diabetes. This is because caffeine in coffee affects insulin sensitivity. Some people may experience a significant increase in blood sugar after drinking an Americano and their blood sugar levels last longer.
 
People taking blood sugar-lowering medications may have their effects reduced, so it is best to avoid caffeine as much as possible. In particular, it is better to avoid coffee and caffeine-containing drinks after meals.

4. 50s Women in Menopause

The fourth group is women in their 50s in menopause. This is because of the risk of osteoporosis. You know that caffeine in coffee has a diuretic effect that promotes urination. However, calcium is also excreted in this urine, so you need to be careful.
 
In addition, there are reports that caffeine increases bone mineral density loss and, in particular, increases the risk of hip fracture. Studies have also reported that older women who consume more than 300 mg of caffeine are at a higher risk of bone loss.

5. People with Cardiovascular Disease

The fifth group is people with cardiovascular disease. Caffeine stimulates the sympathetic nervous system, which makes the heart beat faster and maintains a state of tension, greatly affecting blood pressure. In particular, mixed coffee requires extra caution because it increases blood cholesterol levels.
 
Caffeine can interfere with the electrical stimulation that causes the heart to contract and expand, so people with arrhythmias should avoid coffee as much as possible.

In conclusion

Even if you are healthy, it is best not to exceed 400 mg of caffeine per day. To put it simply, it is best not to drink more than 3 cups of coffee. Caffeine takes about 5 to 6 hours to take effect in our body and is completely excreted in about 24 hours, so it is best not to drink coffee in the afternoon.