One of the world's top three beverages, coffee, has gradually permeated into our lives and even become a symbol of modern living.

South Koreans consume an average of 200 cups of coffee per year, while Americans consume 400 cups, and Europeans consume 750 cups.

To cope with the toils of a whole day, some people choose to refresh themselves with a cup of coffee or tea, letting caffeine invigorate and awaken them. However, as with all things, moderation is key.

Occasional consumption may not lead to addiction, but drinking more than five cups a day is excessive, and certain groups should be especially cautious with their intake.

1. Addiction or withdrawal symptoms:

Feeling tired, sleepy, fatigued, or experiencing headaches, or pain when not consuming coffee indicates a dependence or withdrawal from caffeine.

2. Osteoporosis:

Some studies have found that caffeine acts as a diuretic, leading to the loss of calcium, magnesium, potassium, and other electrolytes from the body. Therefore, caffeine is listed as a risk factor for osteoporosis. Scientists are currently conducting further research in this area.

For individuals with osteoporosis, it is recommended not to exceed two cups of coffee per day (one cup of 240 cc coffee contains approximately 100 mg of caffeine). They should also supplement their calcium intake to reduce the severity of osteoporosis and lower the rate of hip fractures.

3. Iron deficiency anemia:

Iron deficiency anemia can result from inadequate dietary intake of iron, acute or chronic bleeding, and excessive consumption of coffee and tea, as the tannic acid in them can hinder iron absorption. Anemic individuals who consume coffee to stay alert may exacerbate their condition.

4. Gastritis and peptic ulcer patients:

Caffeine stimulates the secretion of gastric acid, leading to indigestion and heartburn. Individuals with peptic ulcers or symptoms such as gastric discomfort, heartburn, or stomach pain after drinking coffee should limit their coffee consumption.

5. Cardiovascular disease patients:

Cafestol in coffee triggers signals from the small intestine to the liver, instructing it to stop breaking down cholesterol. This can lead to an increase in cholesterol levels, particularly LDL (bad cholesterol), which increases the risk of blood vessel blockages and atherosclerosis.

According to a study published in the journal Pharmacological Research, the brewing method affects the cafestol content in coffee. Drip coffee has almost no cafestol, while longer brewing times or hotter water results in higher cafestol levels.

6. Gallstone patients:

Even small amounts of caffeine can stimulate gallbladder contraction, potentially causing pain in individuals with gallstones. Therefore, gallstone patients should avoid drinking coffee.

You can still enjoy the benefits of coffee, such as accelerating metabolism, refreshing yourself, and enhancing alertness if you don't have the aforementioned issues and can pay attention to the quantity and quality of the coffee you consume.