How old are you really? Know your biological age

Age is considered just a number — and a number that you might be able to change. This is the idea proposed by Tally Health, a new startup that is part of a group of companies that commercialize tests that provide customers with information about their “biological age".

What is a biological age test

Have you heard of home tests like the ones in 23andMe, Ancestry or Earn, that scan your DNA to provide information about ethnic heritage and health risks? Now, a wave of startups is commercializing tests that claim analyze your blood, urine, or a cheek swab (collection with swab of genetic material) to reveal your biological age.

The tests measure epigenetic patterns, or changes in the body that affect how genes behave. Unlike a chronological age, which advances at the same pace for everyone, biological age is the rate at which cells, tissues and organs appear to decline — and this can vary, depending on a person's health history.

How the Tally Health test works

A tally health, recently launched, is one of twelve companies offering tests to analyze the biological age of the body. The company's co-founder, Harvard University biologist David Sinclair, describes the test as a credit score for the body. The user swabs his cheek, sends the sample in the mail and the company returns his biological age.

Sinclair explains that if the result shows that the user is younger, great, the idea is to keep him young and even rejuvenate him as he chronologically ages. On the other hand, if the result indicates a biological age older than the chronological age, the company is available to reverse this situation, causing the biological age not only to return to the average, but to be below it.

Factors that affect biological age

Both genetics and lifestyle contribute to the aging process. Choices such as diet, exercise, tobacco and alcohol consumption cause epigenetic changes that affect how genes behave. Additionally, exposure to stress, trauma, and pollution can have negative effects.

Scientists believe that the sum of all these factors affects a person's biological age, but Sinclair believes that genetics are far less important than factors that are in a person's control. (Sinclair is 53 years old, but according to the Tally Health test, her biological age is similar to that of a 43-year-old.)

David Sinclair

David Sinclair is a renowned researcher in the field of longevity and anti-aging. He is known for his research on the resveratrol, a compound present in red grapes that it considers a “miracle molecule”. However, other researchers have differing opinions about the possible benefits of resveratrol, especially in animal tests.

Despite this, Sinclair take daily resveratrol supplements and continues to study its effects in his laboratory at Harvard. In addition to his research, he has also founded several biotech companies focused on longevity, and his 2019 book, “Lifespan: Why We Age–and Why We Don't Have To,” became a New York Times bestseller. .

What we're trying to do, at a high level, is change the way we age.

Melanie Goldey, CEO of Tally Health.

New York-based company Tally Health offers a service beyond providing each client's biological age. The company offers an action plan with personalized lifestyle recommendations, such as sleeping more, sitting less, minimizing stress, or eating more vegetables — things that most people could benefit from.

prices and demand

Users can choose between a one-time test for US$229 (R$ 1520,39) or get a subscription to test every three months and monitor their biological age over time. According to Goldey, a spokesperson for the company, "we think this is a good time for people to get their action plan, empower themselves with the information, choose the adjustments they want to make and implement some changes."

She reports that Tally Health had huge demand upon its launch, with a waiting list of over 270.000 people. However, the company did not disclose the number of people who signed up for the membership options, which range from US$129 (R$ 655,95) to US$199 (R$ 1011,90) per month.

As much as other epigenetic aging tests available on the market, Tally Health examines DNA methylation patterns, the chemical tags in the DNA code that affect gene activity. The relationship between DNA methylation and aging was established by scientists in the 1970s.

Epigenetic aging clocks

In 2013, Steven Horvath, a geneticist and biostatistician at UCLA, created the first aging “clock” epigenetic analysis based on these changes. The watch is a predictive test that uses data from 8.000 biological samples from 51 healthy human tissues and cell types to measure DNA methylation patterns associated with aging and disease, and uses an algorithm to estimate a person's age.

The new generation of epigenetic clocks aims to predict not only biological age, but also life expectancy and future health. O PhenoAge, created by Morgan Levine of Yale University in 2018, uses blood samples to calculate the risk of death as well as the risk of cancer, cardiovascular disease and Alzheimer's.

In 2019, a team led by Steven Horvath and Ake Lu developed the Grim Age, an improved version of the previous epigenetic clock that can predict life expectancy of a person from a blood sample.

These watches were developed to be used by researchers who aim to evaluate the anti-aging effects of substances or lifestyle changes in animals or individuals. According to studies performed, it was found that those with a higher biological age in relation to their chronological age are more susceptible to certain illnesses and death. As a result, companies emerge with the intention of creating their own watches or adapting existing ones in direct tests for consumers.

Tally Health and other commercially available tests

The technology used in Tally Health's test was developed in Sinclair's laboratory at Harvard University and was described in a pre-published article released last year.

By collecting cells present in a buccal swab, the company is able to estimate a person's biological age, analyzing DNA methylation patterns and comparing them with samples from 8.000 individuals, aged between 18 and 100 years, collected by the company . According to Goldey, about half of the samples were collected from men and the other half from women, while 30% were from non-white individuals.

There are other tests available on the market: since 2017, the company Zymo Research, based in Irvine, California, has offered a blood or urine test called myDNAge for $299, based on Horvath's biological aging clock. The company provides a custom report which includes information about the client's metabolic health, methylation activity, and potential risk of age-related diseases.

In 2019, New York City-based supplement maker Elysium Health released a $299 biological aging test it developed in partnership with Levine, who currently works at Altos Lab, a $3 billion life extension company in San Diego.

Uncertainties and studies

Some people age more slowly and live long, healthy lives, while others age more quickly and have an early onset of chronic disease. Biological age is a way of trying to summarize these differences between people.

Daniel Belsky, associate professor of epidemiology at Columbia University

According to Belsky, it's still unclear whether current epigenetic tests are sensitive enough to detect lifestyle changes that people might make in a relatively short period of time.

Even if they are capable, repeated tests have yet to be done on enough people to determine whether their scores correlate with changes in their overall health and longevity. According to Belsky, "We still don't have a great deal of knowledge about how well they serve as monitors of individual aging progress."

diet study

Num recent study conducted by Belsky and his colleagues at Columbia University, investigated whether a low-calorie diet could have anti-aging effects in individuals. For this, healthy adults were selected to participate in a two-year clinical trial, divided into two groups: one that followed a normal diet and another that followed a diet restricted by 25% of calories.

During the study, blood samples were collected from participants at baseline, one year later and at the end, using three measures to assess aging: PhenoAge, GrimAge and a clock developed by Belsky and colleagues called DunedinPACE, which estimates the rate of aging of a person.

diet effects

The PhenoAge and GrimAge watches found that calorie restriction did not have a significant impact on a person's biological age. However, the DunedinPACE trial revealed that the diet actually slowed aging.

Belsky explained that "some of these tools may not be optimized to detect small changes in biological age." The company TruDiagnostic, located in Kentucky, markets the DunedinPACE as a consumer test.

Charles Dupras, a bioethicist at the University of Montreal who has researched direct-to-consumer epigenetic testing, said such tests can be beneficial to people by serving as a encouraging the adoption of healthier habits.

“Having access to this tool can be a positive source of motivation for people.”

Charles Dupras, a bioethicist at the University of Montreal.

However, Dupras warns that companies must be careful not to make exaggerated claims about the possible benefits of these tests. Furthermore, it is not known for sure whether these tests, being relatively new, actually encourage people to make healthier decisions.

Potential of tests

Eric Verdin, president and CEO of the Buck Institute for Research on Aging in Novato, Calif., expressed his enthusiasm for the potential of biological aging tests and revealed that his institute is one of several groups developing such tests.

"They are excellent research tools, but it's too early to put them in the spotlight."

Eric Verdin, president and CEO of the Buck Institute for Research on Aging.

According to him, firstly, it is not clear whether all the tests available on the market have been validated by other scientists. Furthermore, Verdin cautions that these tests have not yet been evaluated by the U.S. Food and Drug Administration, and therefore are not regulated.

Sinclair believes there is no downside to knowing your biological age. “By having access to that number, it's like you have a dashboard on your body,” he said. "We believe it gives you the power and determination to make a change in your life."

In summary, although the possibility of knowing your biological age can be a source of motivation to adopt healthy habits, it must be borne in mind that these tests are still recent and need to be validated. Thus, before submitting to a biological aging test, it is important to seek medical advice and scientific to better understand its limitations and potential.

reviewed by Dacio Castelo Branco in 10 / 04 / 2023

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Source: The Guardian, Wired, tally health, Science, TechnologyReview