Study Links Coffee Consumption to Obesity, Substance Use, and Mental Health Traits

A new study, published in Neuropsychopharmacology, uses two large gene databases to identify health traits associated with coffee consumption. Although the research does not answer the enduring “Is coffee good or bad?” question, they unearth some interesting connections. 

For instance, they found strong genetic links between coffee consumption and health outcomes like obesity and substance use. They also identified links to mental health conditions, although these were less straightforward. Globally, coffee is one of the most commonly consumed drinks, and caffeine is the most widely consumed psychoactive drug. 

Yet, despite decades of research, links between coffee and health are still being examined.There is some evidence that moderate coffee intake is linked to a reduced risk of liver disease, cardiovascular disease, certain cancers, and neurodegenerative conditions. 

On the other hand, coffee may also be associated with the use and misuse of other substances and some cancers. It is a complex situation, likely involving genetics, how much someone drinks, and a wide range of other factors. As strange as it seems, how much coffee or caffeine an individual drinks might be partly inherited from their parents. Previous research on twins has suggested that caffeine-related traits are 36–58% heritable. 

To investigate these relationships, scientists use so-called genome-wide association studies (GWAS). In short, these studies analyze participants’ whole genomes to identify gene variants associated with a given trait. 

They focus on single nucleotide polymorphisms (SNPs). These are the most common form of genetic variants and involve change in a single nucleotide, the building blocks of DNA.Researchers then look for links between particular SNPs and the trait of interest. In this case, coffee consumption. As expected, in both datasets, the scientists found evidence of a genetic disposition to coffee consumption. 

Researchers were also able to confidently identify specific genes that influenced coffee consumption, including some that influence how quickly caffeine is metabolized. 

In both the U.K. and U.S. datasets, the scientists noted positive associations between coffee consumption and health outcomes, including substance use and obesity. This study found that certain genes were found consistently among enough participants to say the two may be linked. 

The genetics of coffee intake positively overlapped with the genetics of obesity and related traits. This does not mean that coffee intake promotes obesity. Rather, it means that the genetic differences among individuals that influence coffee intake also influence obesity. The development of obesity is multifactorial and unlikely the product of genetics alone.In another part of the study, the scientists carried out a phenome-wide association study (PheWAS). 

Researchers use genetic data to train a model to predict the genetic tendency to consume coffee. Then, using another population, they “explored whether people who carry those coffee intake-associated genetic variants are more or less likely to have different health outcomes. 

More research is necessary and suggested checking in with one’s healthcare provider because many factors, including medical history, influence how much caffeine intake is safe for an individual. 

If one has a sensitive stomach or gut issues like irritable bowel syndrome, then coffee might not be the best drink for you. For some people coffee can speed up how quickly food moves through their gut, making them urgently dash to the bathroom. And some are caffeine sensitive, so coffee can make them uncomfortably jittery. 

Overall, the health benefits and risks of coffee are still under scrutiny. As with many health questions, the pros and cons probably vary from person to person. Thanks to coffees near ubiquity, more research is sure to follow.