Just 3 Drinks Per Week May Raise Dementia Risk

Although we have already reported on the potential health benefits of alcohol, such as: For many benefits, such as improving mood or supporting heart health, a growing body of research suggests that drinking alcohol has far more negative consequences than benefits.

In fact, evidence has emerged that calls into question some of these previous findings and the supposed benefits of alcohol. For example, in January 2025, the US Surgeon General issued an urgent warning about alcohol consumption and cancer risk. The recommendation states that alcohol consumption increases the risk of at least seven types of cancer, including oral, breast, liver and colon cancer. It also states that alcohol is now the third most common preventable cause of cancer and is responsible for 100,000 new cancer cases and 200,000 deaths per year in the United States alone.

And what about the brain? If you like to unwind with a cocktail or want to muster up some “liquid courage” to relax and have fun while out with friends, alcohol may seem beneficial. But is it? There is older evidence to suggest that light to moderate alcohol consumption may have protective benefits for the brain. However, recent research calls these results into question.

Researchers from the United States and the United Kingdom jointly examined data from two large studies to clear up the confusion surrounding alcohol consumption and brain health. They said this study was the largest combined observational and genetic study on the topic to date and published their results in BMJ Evidence-based medicine. Let’s break down what they found.

How was this study conducted?

The researchers analyzed data from two large cohorts: the US Million Veteran Program and the UK Biobank. In total, almost 560,000 people were included who were between 56 and 72 years old at the start of the study. Those who took part in the US Million Veteran Program were followed for an average of four years, while the UK cohort had an average follow-up of 12 years.

Both cohorts were observational studies in which demographic information, medical history, medical information, family history, and blood counts were collected from each participant. Observational studies collect information and then group participants based on specific factors to observe specific outcomes. They are essentially a snapshot of time.

In this case, researchers examined whether or not there was a connection between alcohol consumption and people developing dementia. Dementia is a general term for loss of memory, language, problem-solving skills, and other abilities that is severe enough to interfere with daily life. Alzheimer’s disease is the most common form of dementia.

The other part of this study used Mendelian randomization (MR), which takes into account genetic variables that mimic the randomization process. MR tends to be a more accurate method of linking relationships than observational studies because it is less susceptible to confounders and reporting biases from participants and researchers. This genetic analysis included 2.4 million participants.

What did this study reveal?

In the first part of this study, researchers used observational data to find what many previous studies have found: heavy drinkers (>40 drinks per week), non-drinkers, and people with alcohol use disorder (AUD) had a higher risk of developing dementia compared to light drinkers (<7 drinks per week). Specifically, heavy drinkers and non-drinkers had a 41% higher risk of dementia, and those who were alcohol dependent had a 51% higher risk.

However, the genetic analysis of Mendelian randomization did not agree with the results of the observational study. Instead, these results suggest that as genetic alcohol consumption increases, so does the risk of dementia – meaning even light drinkers are at increased risk and non-drinkers are at lower risk.

For example, the risk of dementia increased by 15% for every additional one to three drinks per week. And a doubling of the genetic risk for AUD was associated with a 16% higher risk of dementia. These results suggest that there is no “safe” recommendation for alcohol consumption when it comes to dementia.

But why did the observational study suggest that non-drinkers had a higher risk of dementia while light drinkers had a lower risk? Researchers point out the limitations of observational studies, including bias and inaccurate data reporting by participants. They also state that observational studies only measure transient, fluctuating traits influenced by environmental and life-stage factors, whereas Mendelian randomization uses stable, long-term traits.

Researchers note that while Mendelian randomization is more accurate at identifying relationships that suggest causality, it still has its limitations. In this case, they state that the strongest associations were found among people of European ancestry, so these results may or may not apply to other races and ethnicities. They also note that MR relies on genetic assumptions that cannot always be verified.

How does this translate to real life?

If you’re struggling with the tug-of-war of wanting to drink with friends but want to be healthy at the same time, it’s important to think about what we currently know about alcohol. Aside from alcohol being linked to an increased risk of cancer, we know that it also affects the gut microbiome, leading to an increase in endotoxin levels. These toxins increase inflammation in your body, which is linked to pretty much every disease imaginable, from heart disease and cancer to diabetes and autoimmune diseases.

Regular alcohol consumption is also associated with a decrease in gray and white matter, i.e. smaller brains. And this decrease in brain volume was seen even in people who drank just one drink per day, with the loss of brain mass increasing as the amount of drinks increased. Another study suggests that heavy drinkers (eight or more drinks per week) had a higher risk of dementia than non-drinkers, including a whopping 133% higher risk of brain lesions.

When it comes to drinking or not drinking, it’s a matter of weighing the pros and cons and deciding which is more important to you. It is also advisable to examine the reasons why you decide to take it. For example, if you drink to relax, consider other ways to relax, such as taking a walk, practicing yoga or meditation, journaling, going into nature, preparing a healthy meal (maybe we have a few ideas!), or calling a friend.

Consider switching to mocktails if you drink alcohol because you like the taste. We love our Mojito mocktails, Tart Cherry Nighttime mocktails or Sangria mocktails with no added sugar. And if you’re drinking to fit in—and maybe even having trouble stopping your friends from pouring you a drink—maybe it’s time to change your friend group.

Our expert opinion

Drinking is a very personal decision and it is wise to consider the potential damage alcohol can do to your body and brain. This study suggests that any amount of alcohol, including light and moderate alcohol consumption, has negative effects on brain health and increases the risk of dementia.

If you feel like you can’t handle life without alcohol, it may be time to get help. If you or someone you know is struggling with alcohol dependence, alcohol abuse, or addiction, reach out Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline. For information about support and treatment facilities near you, call 800-662-4357. It’s important to note that quitting cold turkey can be dangerous because your body can become physically dependent on alcohol. For this reason, alcohol detoxification is recommended under medical supervision.