Current Events in October 2025

• Even light drinking (under seven drinks a week) showed no protective effect in the largest combined study to date.

• Genetic analyses suggest the more alcohol you’re predisposed to consume, the higher your dementia risk.

• The drop in drinking before diagnosis hints that earlier studies showing benefits may have been misled by reverse causation.

If you’ve ever heard that a glass of wine a day is good for your brain, recent research suggests it’s time to pause and reconsider. 

A new large-scale study combining observational data and genetic methods argues that any amount of alcohol might increase the risk of dementia. What looked like a protective effect of light or moderate drinking in past studies could, in fact, be a misleading artifact. 

The findings challenge a long-held assumption: that low levels of alcohol are harmless — or even beneficial — for cognitive health.

“Our study findings support a detrimental effect of all types of alcohol consumption on dementia risk, with no evidence supporting the previously suggested protective effect of moderate drinking,” the researchers wrote. 

The study

To tackle this question, researchers used two main strategies:

1. Observational data. They drew from two major biobank projects — the U.S. Million Veteran Program and the U.K. Biobank — to examine real-world drinking habits and incidence of dementia. Participants between 56 and 72 years old were followed over time until they developed dementia, died, or reached the end of follow-up (2019 for MVP, 2022 for UKB). Alcohol intake was self-reported (frequency, volume) and supplemented with the AUDIT-C screening tool for risky drinking behaviors (like binge drinking). In total, 559,559 people entered the observational analyses, and 14,540 developed dementia during the follow-up.

2. Mendelian randomization (genetic analysis). This method treats genetic variants associated with alcohol consumption as proxies (or “instruments”) for long-term drinking behavior. In this study, they considered three different genetic measures: predisposition toward average weekly drinks, risky drinking, and alcohol dependence. The goal: to minimize confounding (other factors influencing both drinking and dementia) and test whether a causal link might exist. For the genetic analyses, they drew on genome-wide association study (GWAS) data covering millions of people.
   

By combining both approaches, the researchers hoped to triangulate evidence: observations can show patterns, and genetics can help clarify whether those patterns suggest causation.

The results

In the observational analyses, the relationship between alcohol and dementia looked U-shaped. This means that both low and high levels of something are linked to worse outcomes, while moderate levels are linked to the best outcomes.

For this study, that looked like: both abstainers and heavy drinkers (40+ drinks/week) had about a 41% higher risk of dementia, compared with light drinkers (less than seven drinks per week). That figure climbed to 51% higher for those with alcohol dependence. That pattern might look like light drinking is protective — but observational data alone can be misleading.

The genetic (Mendelian randomisation) analyses told a different story: there was no protective effect at low levels. Instead, dementia risk rose steadily with greater genetically predicted alcohol intake across all categories. For example, each additional one to three drinks per week (by genetic risk) was linked to a 15% higher dementia risk. Doubling the genetic propensity for alcohol dependence was tied to a 16% increased risk. In short, more drinking (genetically indicated) = more risk, in a roughly linear fashion.

One particularly telling insight: many individuals who were later diagnosed with dementia had gradually reduced their alcohol consumption in the years before diagnosis. That suggests that early (preclinical) brain changes might lead people to cut back — a phenomenon called reverse causation. If so, earlier observational studies that found benefits from light drinking may have been capturing that effect, rather than a true benefit of alcohol.

The authors do note limitations: the strongest associations came from those of European ancestry (because of sample sizes), and Mendelian randomization depends on certain assumptions that can’t be fully tested. Nonetheless, they conclude that their findings oppose the idea of a “safe” or beneficial low dose of alcohol for brain health and argue that reducing alcohol intake could be a meaningful strategy for dementia prevention.

“Our findings highlight the importance of considering reverse causation and residual confounding in studies of alcohol and dementia, and they suggest that reducing alcohol consumption may be an important strategy for dementia prevention,” the team wrote. 

• A recent study compared the cost of 33 neurologic drugs via a direct-to-consumer (DTC) pharmacy and via commercial insurance.

• Out-of-pocket costs were on average 75% higher under the DTC model, but total system costs (which include insurance payments) were 413% lower.

• For patients without insurance, the DTC route might offer a viable alternative—though it currently covers less than half of all neurologic drugs.

If you’ve ever paid for a prescription and winced at the price — and then wondered what your insurance was really doing for you — you’re not alone. 

A study highlighted by Ohio State News explores whether online, direct-to-consumer pharmacies (like the Mark Cuban Cost Plus Drug Company) could compete with traditional insurance-based models. 

“I had heard about the Mark Cuban pharmacy through colleagues and thought it would be interesting to compare the costs because his pharmacy is very direct-to-consumer – they cut out the middleman and whatever is advertised on the website is what you’re paying for, and that’s your only cost,” researcher Amanda Gusovsky Chevalier said in a news release. 

The study

Here’s how the researchers set up the trial: 

• They focused on neurologic medications — used for conditions like Alzheimer’s, MS, Parkinson’s, and more. 

• From 79 medications, they found 33 that were available through the DTC pharmacy (Mark Cuban’s Cost Plus).

• For each drug, they collected the out-of-pocket (OOP) cost under the DTC model (i.e. what a person would pay themselves) and estimated what it would cost under commercial insurance (including what the patient + insurer would pay). 

• Because insurance-based data came from 2012–2021, they used statistical modeling to project what those insurance costs might look like in 2024. 

• They compared two main outcomes:
    1. Out-of-pocket difference (i.e. what you pay directly)
    2. Total cost difference (i.e. sum of what the patient + insurer pay)

• They also repeated comparisons focusing only on generic drugs (i.e. leaving out brand-name ones) to see how much that changes things.

What they found: The upside (and the catch)

The results show a mixed but compelling picture:

Out-of-Pocket Costs:

• On average, the DTC model’s out-of-pocket cost was 75% higher than what insured patients would pay through traditional commercial pharmacies.

• However, for many medications, that difference was relatively small in dollar terms. In 76% of the drugs studied, the OOP difference was under $200 per year.

• Only two medications — teriflunomide and droxidopa — had lower OOP costs via the DTC route.

• Among generics only, none of the DTC drugs had lower OOP costs.
  

Total System Costs:

• The real eye-opener: on average, DTC’s total costs (patient + what insurer would have paid) were 413% lower than in the insurance-based model. 

• 18 out of the 33 medications (~55%) showed lower total annual costs when purchased via the DTC pharmacy.

• A few drugs stood out with especially large cost reductions (e.g. teriflunomide, dimethyl fumarate, droxidopa).
  

One caveat: because the DTC pharmacy’s catalog is limited — it only listed 33 of 79 neurologic drugs — the model isn’t yet a full replacement. 

Also, if everyone switched to DTC, the study estimated that patients’ aggregate out-of-pocket spending would increase by about $82 million — but total costs across the system might drop. 

In short: for insured patients, the DTC model often means paying more out of pocket, so it may not seem appealing. But for the system at large — and especially for people without insurance — it has real promise. 

“Our research has shown that the costs of medications just continue to rise through insurance plans, and it’s really important to find ways for patients to access medicines,” Gusovsky Chevalier said. 

“I think this adds to a larger body of evidence showing that these direct-to-consumer pharmacies have the potential to disrupt the market in some significant way in the future. It’s important for people to know that online pharmacies like this are available.”