How does caffeine in coffee and tea affect insulin and blood sugar?

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Coffee is one of the most popular beverages in the world and is increasingly consumed worldwide. Coffee contains many biologically active components, the most important of which is caffeine, which is also found in tea and cola drinks. How does caffeine affect insulin and blood sugar?

Diabetes is a rapidly growing global problem with major social, health and economic consequences. It is a disease caused by a deficiency of the hormone insulin or a weakness in the natural response of the body’s cells to insulin, which enters the sugar present in the blood (glucose) into the cells. In both cases, the result is similar, as blood levels rise. Blood glucose is above the normal limit, and this leads to negative effects on the body sooner and later.

Insulin is a hormone made by beta cells in the pancreas, which is an organ located between the stomach and the spine. The pancreas secretes insulin into the bloodstream after a person eats food, in response to high sugar in the bloodstream.

Glucose constitutes the energy into which the food that a person eats is transformed, and it is secreted into the blood, so the body’s cells take it and burn it to give them the energy necessary for their vital processes. To do this, it needs the hormone insulin, which makes glucose move from the bloodstream to the cells.

The effect of caffeine on insulin

A growing body of research suggests that people with type 2 diabetes react to caffeine differently. It can raise blood sugar and insulin levels in people with the disease, according to a report in WebMed.

One study looked at people with type 2 diabetes who took a 250-milligram caffeine tablet at breakfast and another at lunchtime. This is approximately equivalent to drinking two cups of coffee with each meal. The result was that their blood sugar levels were 8% higher compared to days when they did not consume caffeine, and their readings jumped more after each meal.

This is because caffeine can affect how your body responds to insulin, the hormone that allows sugar to enter your cells and turn into energy.

Caffeine may decrease insulin sensitivity, meaning your cells don't react to the hormone as much as they did before. They do not absorb as much sugar from your blood after you eat or drink. This makes your body produce more insulin, so you have higher levels after meals.

If you have type 2 diabetes, it means your body doesn't actually use insulin well. After meals, the blood sugar level rises above normal. Caffeine may make it more difficult to control blood sugar. This may lead to high blood sugar levels. Over time, this may increase your risk of diabetes complications, such as nerve damage or heart disease.

How caffeine affects blood sugar

Caffeine raises levels of some stress hormones, such as epinephrine (also known as adrenaline). Epinephrine can prevent cells from processing too much sugar, and it may also prevent the body from producing too much insulin. It blocks a chemical called adenosine, which plays a large role in the amount of insulin the body produces, and it also controls how cells respond to it.

Also, caffeine negatively affects sleep, as too much of it can keep a person awake. Lack of sleep may also reduce insulin sensitivity.

It only takes about 200 milligrams of caffeine to affect blood sugar. This is the amount found in about one or two cups of coffee or 3 or 4 cups of black tea.

The amount of caffeine in the drink varies depending on its type and method of preparation. For example, a cup containing 30 milliliters of concentrated coffee, boiled coffee, such as Turkish coffee or expresso coffee, may contain between 40 and 75 milligrams or more of caffeine, while a cup of black tea (240 milliliters) contains approximately 60 milligrams of caffeine.

So caffeine is harmful to diabetics?

It's complicated, and it depends on the nature of the person's body and how well it handles caffeine. For example, people with diabetes who drink coffee regularly do not suffer from higher blood sugar levels compared to those who do not drink it regularly.

Some experts believe that your body gets used to this amount of caffeine over time. But other research shows that caffeine can still cause a sugar spike, even if you always start your day with a cup of coffee.

To find out if caffeine raises your blood sugar, talk to your doctor. He may recommend that you do a blood sugar test in the morning after your usual cup of coffee or tea. Then you will do the test after stopping the drink for a few days. When you compare these results, you'll know if caffeine had an effect.

What about studies linking coffee to protection against diabetes?

Studies indicate that coffee may reduce your chances of developing type 2 diabetes, and experts believe that the reason for this is that the drink contains a high percentage of antioxidants that may play a role in protecting against diabetes.

But if you already have type 2 diabetes, you may not benefit from coffee. The caffeine in a cup of coffee makes controlling blood sugar more difficult. If your levels rise after your morning cup, you may want to switch to decaf. Although this drink contains a small amount of caffeine, it does not have the same effect on blood sugar or insulin.

Source: Al Jazeera + agencies