Harvard's Latest Research: One Glass of Wine a Day Reduces the Risk of Death by 20%?

On March 12, 2025, a research team from Harvard Medical School published a research paper titled "Lipid Profiles After Changes in Alcohol Consumption Among Adults Undergoing Annual Checkups" regarding the relationship between moderate alcohol consumption and cardiovascular health in *JAMA Network Open*, a sub-journal of the *Journal of the American Medical Association* (JAMA). This large-scale study, which tracked more than 50,000 Japanese people over a period of 10 years, revealed that moderate alcohol consumption can reduce the level of "bad cholesterol" - low-density lipoprotein cholesterol (LDL-C), and at the same time increase the level of "good cholesterol" - high-density lipoprotein cholesterol (HDL-C). However, once a person stops drinking alcohol, the level of bad cholesterol will rise, and the level of good cholesterol will decrease.

## The Impact of Alcohol Consumption on the Cardiovascular System from the Perspective of "Cholesterol"

This research was of a large scale. The research team selected the data of residents who had received at least two health check-ups at the St. Luke's International Hospital Health Screening Center in Tokyo, Japan, between October 2012 and October 2022. Eventually, a total of 57,691 eligible participants (53% of whom were women) were included in the study, with a cumulative total of 328,676 medical examination records.

Based on the screened population, the research team established two cohorts to analyze the long-term effects of changes in alcohol consumption behavior on the levels of "bad cholesterol" LDL-C and "good cholesterol" HDL-C. Cohort 1 focused on the initiation of alcohol consumption behavior, while Cohort 2 focused on the behavior of quitting drinking.

## The Close Relationship between Bad Cholesterol and Myocardial Infarction and Cerebral Infarction

Atherosclerotic plaques are the core issue of cardiovascular diseases. Dreaded diseases such as stroke, cerebral infarction, myocardial infarction, sudden cardiac death, and coronary heart disease all have a common origin - arterial plaques. Arterial plaques are markers of individual atherosclerosis, and their main component source is "bad cholesterol" - low-density lipoprotein cholesterol (LDL-C).

Atherosclerosis is usually asymptomatic. When the degree of vascular stenosis is less than 50%, the human body often has no obvious sensation. Plaques have the characteristic of random rupture. Once they rupture and form a thrombus, it may lead to cerebral infarction and myocardial infarction. Atherosclerosis can be called the number one health killer of human beings, and cardiovascular diseases are the leading cause of death in humans. According to the data from the World Health Organization (WHO) and the *Global Burden of Disease Study*, in 2023, more than 20.1 million people around the world died from cardiovascular diseases. In China, the number of deaths due to cardiovascular diseases ranks first, with 2 out of every 5 deaths being caused by cardiovascular diseases.

Data from the National Health Commission of China shows that the incidence risk of stroke among Chinese people is 39.9%. According to the data of the Global Burden of Disease (GBD) Study in 2019, the number of stroke patients in China in 2019 was 3.9 million. Stroke causes 2.3 million deaths in China every year, and sudden cardiac death due to myocardial infarction causes 500,000 to 1 million deaths every year.

## Alcohol Consumption Can Reduce Bad Cholesterol and Increase Good Cholesterol

"Bad cholesterol" - low-density lipoprotein cholesterol (LDL-C) can lead to the accumulation of arterial plaques, while high-density lipoprotein cholesterol (HDL-C) reduces the deposition of cholesterol in the blood vessel walls and lowers the risk of atherosclerosis by transporting the excess cholesterol in the blood vessel walls to the liver for metabolism and excretion. Figuratively speaking, HDL-C is the "scavenger of blood vessels" and is thus known as "good cholesterol". The research team from Harvard University found that alcohol consumption can reduce the level of bad cholesterol and increase the level of good cholesterol.

The researchers first focused on the group of people who "started drinking alcohol" (Cohort 1) and observed the impact of drinking one glass of wine a day on blood lipids. Here, one standard glass of wine is defined as containing 10g of pure alcohol. Specifically, for different types of alcoholic beverages, a bottle of beer with an alcohol content of 3.5% is approximately 350 - 500mL; a glass of red wine with an alcohol content of 13% is about 150mL; and a small cup of spirits with an alcohol content of 40% is approximately 50mL. The study found that among those who just started drinking, the level of "bad cholesterol" (LDL-C) decreased, and the level of "good cholesterol" (HDL-C) increased. Such a result is really surprising. Moreover,