Basic knowledge of Fine Coffee right and wrong about Coffee

There are many quotations of petty bourgeoisie, but those about drinking coffee are more classic. For example, "when I'm not at home, I'm in the cafe. I'm not in the cafe. I'm on my way to the cafe." After Starbucks coffee in Seattle has become popular all over the world and become a way of life, more and more people drink coffee in China. But there is a lot of right and wrong about coffee, which is not only about lifestyle and taste, but also about people's health, and the latter is the most important.

Coffee and kidney stones

Coffee has always been a lot of right and wrong, because it is the needs of many people's life, people ignore it. But a recent study has come to the conclusion that people have to be vigilant, especially coffee drinkers. The result of this study is that people who drink more coffee are more likely to have kidney stones, so coffee should not be drunk too much. Of course, people with a history of kidney stones and those who are prone to kidney stones should pay more attention, because the amount of coffee contained in two cups of coffee is enough to affect them, resulting in an increase in the secretion of calcium ions in their urine, thus increasing the risk of developing kidney and urethral stones.

So patients with kidney stones should have less than two cups of coffee a day or the equivalent of two cups of coffee, while normal people should not more than double this amount, that is, four cups of coffee. The concept of two cups of coffee is 16 ounces (one liquid ounce equals 2.841 liters and one percent equals one pound), which translates to no more than 0.455 litres of coffee per day. Normal people should not exceed 1 liter. Of course, you can't use a large cup, because the larger the cup, the more caffeine it contains.

This conclusion was reached by researchers at Washington State University. Calcium in urine is an important component of kidney stones, so too much calcium in urine can increase the risk of kidney stones. The more calcium in the urine, the easier it is to form stones. Previous studies have shown that people who do not have or are not prone to kidney stones secrete more calcium in their urine after drinking coffee or caffeinated foods.

In addition, researchers from the University of British Columbia in the United States and Canada also surveyed the population. They asked 39 patients with kidney stones and 9 normal people who had never had kidney stones to drink caffeinated water after fasting for 14 hours, and to test their urine before and 2 hours after they drank coffee. The results showed that after drinking coffee, the concentrations of calcium, sodium, magnesium and citrate in the urine of people with kidney stones increased, of course, in the urine of people without kidney stones.

More calcium and sodium in urine means an increased risk of kidney stones, while increased magnesium and citrate protect people from kidney stones. However, comparing the increase of calcium and sodium with that of magnesium and citrate, it is obvious that the increase of the latter is not as large as that of the former. Since magnesium and citrate cannot offset the increase in calcium and sodium, too much calcium and sodium can put people at risk of developing stones, regardless of whether they have a history of kidney stones or not.

Coffee increases high blood pressure, which is different between men and women.

Whether it is a man or a woman, drinking a cup of coffee may increase blood pressure. So, what is the principle that coffee increases blood pressure? Moreover, is the mechanism by which coffee increases blood pressure in both men and women the same? Interestingly, studies have shown that coffee can raise people's blood pressure, but there are differences between men and women, although the amount of blood pressure is the same. Caffeine in coffee increases women's heart rate and cardiac output (the amount of blood produced by the heart), while in men, caffeine can cause vasoconstriction. Both pathways result in a rise in blood pressure.

Researchers have long known that coffee can increase high blood pressure, but new research shows that the mechanism of rising blood pressure is different between men and women. So why does the same substance cause the same effect, but the path or mechanism is different?

The researchers found that for women, caffeine mainly increases cardiac output and presses more blood into blood vessels to increase high blood pressure, while for men, caffeine increases high blood pressure by compressing blood vessels and increasing their resistance to blood flow. this increases blood pressure. Although caffeine increases blood pressure in different ways between men and women, the increase in blood pressure is the same. This suggests that caffeine is a potential health hazard for both men and women.

In addition, caffeine can not only increase high blood pressure, but also further increase mental stress during mental tension. Therefore, if a person is developing high blood pressure or already has high blood pressure, it is best to give up coffee or caffeinated foods.

The researchers tested 42 postmenopausal women and 35 men of similar age with either a placebo without substance or a pill containing the caffeine of two to three cups of coffee. These people are in good health, have normal blood pressure and drink coffee regularly.

To induce stress, the researchers asked people who took caffeine to speak in front of a video camera and two researchers in white coats. The researchers then tested their blood pressure. It was found that caffeine increased blood pressure in both men and women, and increased blood pressure by the same amount in both men and women. However, men's response to caffeine is caused by vasoconstriction, while cardiac output does not change. Women did not show vasoconstriction, but cardiac output increased.

Researchers have yet to explain why caffeine does not increase blood pressure in women in the same way as men, but what they can explain is that women who speak in public cause more anxiety than men. Compared with men, when women are anxious, they increase the contraction of their hearts, which in turn increases cardiac output. Judging from this result, caffeine increases women's anxiety and heart response. This has the effect of increasing blood pressure in a different way from men.

Judging from the results of the above studies, although coffee is a way of life and taste, it should not drink more than one or two cups a day for those who are prone to calculi, patients with stones, people with high blood pressure and patients with high blood pressure. On the other hand, normal people should drink coffee at a certain degree, no more than three to four cups a day.