A bathroom scale, a measuring tape and a few questions about lifestyle may tell more about future disease risk than an expensive test that claims to measure biological age.
That is the conclusion of a new study from Tampere University in Finland.
In recent years, so-called biological age tests have become increasingly popular. Some companies sell them directly to consumers as a way to discover whether a person’s body appears younger or older than their actual age.
One widely studied type is known as an epigenetic clock. These tests examine small chemical changes attached to DNA that can change with age, lifestyle and the environment.
The idea is appealing because two people who are both 50 years old may not be aging in exactly the same way. One may be physically healthy and active, while the other may already have several health problems.
Scientists have therefore hoped that biological age measurements could reveal hidden signs of aging and help predict future disease. Some commercial tests can cost hundreds of euros or dollars, and customers may be encouraged to repeat them regularly.
But the new Finnish research raises an important question: do these complicated tests actually predict disease better than information people and doctors can collect easily and cheaply?
Researchers compared several biological age tests with four familiar health measures. These were body mass index, waist-to-hip ratio, smoking and alcohol consumption.
Body mass index, or BMI, compares a person’s weight with their height. Although it has limitations, it can provide a rough indication of whether body weight may be contributing to health risks.
Waist-to-hip ratio compares the size of the waist with the hips. It can help identify fat stored around the abdomen, which has been linked with a higher risk of diabetes, heart disease and other health problems.
Smoking and alcohol use are also well-established health factors. Smoking raises the risk of cancer, heart disease, stroke and lung disease, while heavy alcohol use can damage the liver, heart, brain and other organs.
The study included 1,108 adults who were between 34 and 49 years old when the analysis began. None had been diagnosed with a chronic disease at the start.
The researchers followed the participants for seven to nine years to see who later developed long-term health conditions. They then tested which measurements were most useful for predicting future illness.
The participants came from the Cardiovascular Risk in Young Finns Study, a major Finnish research project that began in 1980. Long-running studies like this are valuable because researchers can examine how health changes over many years rather than relying on a single snapshot.
The results were striking. A model using BMI, waist-to-hip ratio, smoking and alcohol use predicted future chronic disease better than any of the epigenetic clocks examined by the researchers.
This does not mean epigenetic clocks are useless. They can detect biological changes associated with aging and remain valuable tools for scientists trying to understand how aging works.
But finding a statistical link with disease is different from providing useful additional information for an individual. A new test is much more valuable if it improves predictions beyond information that doctors can already obtain from established risk factors.
Senior research fellow Saara Marttila, who led the study, said consumers should think carefully before paying large amounts for biological age testing. For people mainly interested in understanding disease risk, simple measurements and an honest look at lifestyle may currently provide more useful information.
First author and doctoral researcher Daria Kostiniuk made a similar point. If companies describe these tests as major breakthroughs for personal health, she argued, they should be able to show that the tests add meaningful information beyond traditional risk factors.
The research article, titled “Traditional Disease Risk Factors Outperform Epigenetic Clocks as Predictors of Non-Communicable Disease Morbidity in a Middle-Aged Cohort,” was published in the journal Aging Cell on July 9, 2026.
The study has several strengths, including years of follow-up and data from a respected long-term Finnish health project. It also asks a practical question that matters as commercial biological age tests become easier for consumers to buy.
However, the results should not be interpreted as proving that all biological age tests have no future clinical value. The technology continues to develop, and future tests may become better at predicting particular diseases or measuring changes that ordinary health checks miss.
The study also involved middle-aged adults in Finland, so further research is needed to see whether the same results apply equally well to older adults, younger people and populations in other countries.
For now, the findings offer a useful reminder that sophisticated technology is not automatically better technology. When it comes to estimating future health risk, body size, abdominal fat, smoking and alcohol habits still contain a remarkable amount of information.
The practical lesson is reassuringly simple. Before spending heavily on a test that promises to reveal how fast the body is aging, people may gain more useful information by paying attention to the health risks that are already well understood and can often be changed.
Source: Tampere University.
