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Xiao Zhang is a drinker who goes to have a few drinks with friends every day after work, which he feels can relax his mood and enhance friendship. He always said that he only drank in moderation, which did not harm the body, but also helped prevent strokes.
He said he's read a lot of articles saying that drinking one or two glasses of alcohol a day lowers blood pressure, protects the heart, reduces blood clots, and thus reduces the risk of stroke. He also said that these articles are based on science and are not nonsense.
In fact, these articles are based on observational studies that compare differences in stroke incidence between people with different levels of drinking. But such studies have many limitations and confounding factors, such as people's age, gender, genetics, lifestyle, environment, etc., which can affect the risk of stroke.
So is there stronger evidence to prove or deny that moderate drinking prevents stroke? The answer is yes. Some time ago, a new study published in a journal used the latest genetic epidemiological methods to follow up more than 500,000 adults in China for up to 10 years.
The results showed that as alcohol intake increased, so did the risk of high blood pressure and stroke. Light or moderate alcohol consumption did not have a role in preventing stroke. How exactly did this study work? What's so special about it? What does it tell us? Let's take a look together.
Alcohol increases the risk of stroke
Another highlight of the study is that it analyzed not only the effects of alcohol on blood pressure, but also the effects of alcohol on stroke. Stroke is a common cerebrovascular disease with two main types: ischemic stroke and hemorrhagic stroke.
Ischemic stroke is ischemic and hypoxia of brain tissue caused by blockage of blood vessels in the brain, and hemorrhagic stroke is intracerebral hemorrhage caused by rupture of blood vessels in the brain. Stroke can cause severe neurological impairment and even death. Therefore, it is very important to prevent stroke.
So what effect does alcohol have on stroke? The study found that as alcohol intake increases, so does the risk of stroke. Specifically, drinking an extra liquor or two a day or a beer increases the risk of ischemic stroke by 8% and the risk of hemorrhagic stroke by 15%.
This result differs significantly from previous observational studies, which often found that moderate alcohol consumption reduced the risk of ischemic stroke without a clear effect on hemorrhagic stroke.
Why is there such a discrepancy? The study gives a plausible explanation. They believe that the effects of alcohol on stroke are mainly achieved by affecting blood pressure. We know that high blood pressure is the most important risk factor for stroke.
Alcohol can raise blood pressure in many ways, such as increasing cardiac output, contracting peripheral blood vessels, activating sympathetic nerves, inhibiting diures, and so on. So the more alcohol intake, the higher the blood pressure and the greater the risk of stroke.
So why do observational studies find that moderate alcohol consumption reduces the risk of ischemic stroke? This may be due to some confounding factors and biases in observational studies. For example, moderate drinkers tend to have better socioeconomic status, education level, living habits, etc. than non-drinkers or excessive drinkers.
These factors may reduce their likelihood of developing an ischemic stroke, and observational studies have not taken into account differences in ability and sensitivity to alcohol metabolism between individuals, which may also affect their susceptibility to stroke.
This study uses the latest genetic epidemiological methods to exclude other confounding factors and biases, and directly reveals the causal relationship between alcohol and stroke. It tells us a surprising but unmistakable truth: moderate alcohol consumption does not prevent stroke, but increases the risk of stroke.
Second, how important is it to drink less
The final highlight of this study is that it gives a specific number to tell us how much benefit drinking less can bring us. This number is life expectation. Life expectancy refers to the average life expectancy of a person from birth to death, which is an important indicator to measure the health level and quality of life of a person or a group
The study found that if a person starts drinking a little liquor or two a day or two from age 40, his life expectancy can be extended by 1.3 years. If he doesn't drink alcohol at all, his life expectancy can be extended by 4.9 years.
The results are based on a statistical analysis of 10-year follow-up data from more than 500,000 Chinese adults. So why does drinking less alcohol prolong life? That's because drinking less alcohol not only reduces the risk of stroke, but also the risk of many other chronic diseases and cancers.
Alcohol can increase the incidence of cirrhosis of the liver, liver cancer, stomach cancer, esophageal cancer, oral cancer, breast cancer and many other cancers. Alcohol can also damage the function of various cells such as cardiomyocytes, nerve cells, and immune cells, leading to various complications such as heart failure, neurodegenerative diseases, and infectious diseases.
So drinking less alcohol can protect various organs and systems of our body, making us healthier and living longer. Using the latest genetic epidemiological methods, the study gives a specific figure to tell us how much benefit drinking less alcohol can bring us. It tells us the fact that drinking less alcohol can extend our life expectations.
epilogue
Many people have similar misconceptions and habits, and they may be misled by articles that have no scientific basis or are profit-driven. They may not know or care about the harm of alcohol to their body and health, and may not have enough motivation and methods to quit or reduce drinking or alcohol, which is not an easy task.
It requires sufficient awareness and determination, as well as the appropriate means and support. We cannot blindly deny or suppress our desire to drink, nor can we blindly rely on or seek outside help.