Scientists have listed harmful properties

Despite all its advantages, the coffee is not the most healthful beverage in the world. It increases blood pressure, harmful to pregnant women and is addictive. In addition, scientists have found some more harmful properties of coffee, according to health info with reference to

1. Coffee can cause insomnia

Coffee is charging us with energy, but it's his property hurts when we are trying to sleep. The invigorating effect of caffeine begins to be felt within 15 minutes after consumption, but it lasts much longer. In fact, to a stimulating effect came to nothing by half, takes about six hours.

If you want to sleep, try not to drink coffee in the afternoon. Or at least 2-3 hours before bedtime.

2. Coffee affects the the effect of drugs

If you are taking any medication, be sure to ask your doctor whether you can drink it with coffee. This drink can strengthen, weaken or even change the effect of the tablets.

For example, researchers studied the behavior of alendronate (a remedy for osteoporosis) when taken with water and other drinks. It was found that black coffee and orange juice impaired absorption of the drug by 60%. And the action of the thyroid drugs is reduced by 55% if they drink coffee.

Furthermore, the situation could be reversed. Medicines may increase the effects of coffee: you'll feel longer caffeic euphoria. So be sure to check with your doctor.

3. Coffee can aggravate acid reflux

One of the symptoms of acid reflux - heartburn. This is an unpleasant sensation occurs when the lower esophageal sphincter (he shares the esophagus and stomach) does not close on time. Then gastric juice into the esophagus.

Coffee has a very high acidity. Once in the acidic environment (gastric juice), it will lead to the fact that muscle esophageal sphincter to relax. This can cause or contribute to heartburn. The threat is, and decaffeinated coffee. According to some studies, a coffee increases the level of acidity in the stomach by stimulating the production of gastric hormone gastrin.

If heartburn bothers you twice a week or more, you should give up coffee. When heartburn should also be careful to use tea, citrus juices, milkshakes and alcohol.

4. Coffee can cause indigestion

A cup of coffee on an empty stomach stimulates the production of hydrochloric acid, which can lead to serious problems with digestion. Hydrochloric acid is usually produced in stomach when it receives food, and is used for the digestion of proteins and fats.

If one meal it made too much (when I ate a lot of fat or drank a lot of coffee on an empty stomach), the next time it will go is not enough, then the food is not completely digested. This can lead to bloating and discomfort in the stomach, and in severe cases, irritable bowel syndrome and even colon cancer. So try not to drink coffee on an empty stomach.

5. Coffee can act as a laxative

Coffee stimulates contraction of the intestinal muscles. It would seem that it is good, because coffee can help constipation. But this property can also be coffee cause a number of problems, such as gastric emptying. Then the entire contents of the stomach enters the small intestine before food is completely digested and splintered. The nutrients from these foods just do not have time to soak in, as it can lead to intestinal inflammation.

6. Coffee contains carcinogens

When coffee beans are roasted at high temperatures, they can form acrylamide. These substances are considered carcinogenic and genotoxic.

Although dangerous amounts of acrylamide found in various products, coffee - the main source of these substances. The darker roasted coffee beans, the more they acrylamides.

7. Coffee complicates work platelets.

Platelets - blood cells produced in the bone marrow. They help stop the bleeding, sealing the damaged vessel.

In 2008 researchers examined the effect of coffee and caffeine on blood platelets. Study participants consumed capsules or coffee with caffeine and water. Those who drank coffee, the ability of platelets to stick down. And those who received only caffeine, platelet properties are not changed.

It turns out, the coffee will not solve this problem without caffeine. And it can lead to serious consequences for those who suffer from anemia or other diseases associated with blood clotting.

8. The coffee can reduce the chances of pregnancy

According to researchers from the University of Nevada in Reno, the activity of the fallopian tubes is reduced in those who regularly consume caffeine. For these pipes is carried out transportation of eggs from the ovaries to the uterus. A study carried out in mice revealed similar problems to those rodents who were given caffeine.

9. Coffee improves cholesterol.

Cholesterol - a fatty substance required for the production of hormones and other important substances for the organism. But if it stands out too much, it is deposited in the arteries. This leads to various problems with the heart and pressure.

Coffee contains a substance that increases the cholesterol - cafestol. According to one study, five cups of French-press contains 30 mg of cafestol. If for four weeks drinking five cups of coffee a day, the blood cholesterol level rise by 8.6%.

Secure yourself from cafestol help paper filters used in the process of brewing coffee. They detained most of the cafestol.

10. Coffee can cause osteoporosis

Osteoporosis - Bone disease in which bones lose their density and become similar to a honeycomb. It is especially dangerous to the elderly.

For healthy bones need calcium, and caffeine reduces its digestibility. With each cup, we lose about 4-6 mg of calcium. According to scientists, caffeine leads to accelerated loss of bone mineral density in older women.

11. Coffee makes us want sweet

Caffeine increases the craving for fruit juices, soda and other sweet drinks (which are addictive on their own). This was confirmed by a randomized controlled study conducted by Australian scientists.

Participants were divided into two groups: one for a few days, drinking caffeinated beverages, and the second is not. The researchers then analyzed the meals for participants. It turned out that the participants in the first group drank daily 419 ml of sweet drinks, and the participants of the second - only 273 ml.

12. Coffee reduces digestibility iron.

Iron is needed to produce hemoglobin. This protein, which is part of the blood cells, carries oxygen from the lungs to other parts of the body. Even if your diet is rich in iron, or you are taking supplements, the body will be worse to absorb iron if you drink coffee. Total 150-250 ml of coffee reduce iron absorption by 35%.

13. Coffee can cause mastopathy

In this disease in the breast forms a seal, which increase in size and sore during menstruation. The exact cause of the disease is not established, the scientists suggest that it is related to hormones. According to a clinical study, women who consumed per day from 30 to 250 mg of caffeine, mastitis risk increases 1.5 times.

14. Coffee irritates the gastrointestinal tract

Those who suffer from gastritis, ulcer or intestinal problems, doctors are advised to completely give up coffee. Quite possibly, he has led to the emergence of these diseases.

One reason ulcers - the bacterium Helicobacter pylori. Coffee because of its acidity corrodes the stomach lining, and this creates a favorable environment for bacteria. Of course, a strong immune system can protect against this, but not always.

Coffee can cause serious damage to the shell and the small intestine. You can make cramps, colic, constipation or diarrhea.

15. Coffee increases anxiety and stress

Coffee stimulates the production of adrenaline, noradrenaline and cortisol. These hormones include body response "fight or flight". It seems that it is good, because we will feel refreshed and full of energy. Only this energy is produced too much, so we begin to twitch and nervous.

This happens because caffeine blocks the production of gamma-aminobutyric acid (GABA). This neurotransmitter is involved in the braking process in the central nervous system. He saves us from disturbing thoughts. When GABA is not allocated, we experience stress.

16. Coffee can increase the risk of miscarriage

Researchers at the National Institutes of Health and the Ohio State University analyzed the observational data of 500 pairs. The researchers examined the relationship between the presence of chemical substances in the environment, the way of life of parents and their fertility.

It was found that the risk of miscarriage was higher when both partners in the weeks before conception drink per day more than two cups of any beverage with caffeine. Also, the risk of miscarriage increases if a woman drinking coffee in the first seven weeks of pregnancy.

17. Coffee raises blood pressure

You may be years of high blood pressure, but you can not be aware of it. But even if the symptoms are not visible, blood vessels and the heart is still damaged, and this may lead to serious consequences (stroke or heart attack).

Italian researchers analyzed data from more than 1200 patients aged 18 to 45 years, with the first degree of hypertension. Those who drink a lot of coffee, risk to earn high blood pressure (risk increases four times). Those who consume moderate amounts of coffee, the risk increases threefold.

18. Coffee can cause incontinence

Researchers from the University of Alabama found that coffee has on the bladder relaxing effect. The use of more than 200 mg caffeine per day leads to incontinence.


Coffee can be good for health, but it can also harm, especially if you drink too much. Therefore, scientists recommend a moderate amount of coffee - no more than 300 ml of caffeine per day. It is about 3-4 cups of ground coffee (instant or 5 cups). However, if you have high blood pressure, problems with bladder or stomach, better give up coffee altogether.