Aging is an inevitable part of the human experience, but not all parts of the body age in the same way and at the same rate.
Researchers at Stanford University identified four biological aging patterns, or geotypes, that explain why certain parts of some people’s bodies change over time differently than others.
The four types involve the metabolism, immune system, liver and kidneys.
Someone may have a chronological age of 40 but an immune system age of 45, putting them at higher risk for an autoimmune disease such as rheumatoid arthritis, while a liver geotype will likely have a higher risk for liver diseases such as rheumatoid arthritis. cirrhosis.
The team of genetics experts set out to understand why certain people are more susceptible to different aging-related disorders throughout their lives, information they say could give people a better chance of preventing those health problems. as they get older.
To determine the four classes of aging, Stanford researchers took samples of blood, feces, genetic material, metabolites, proteins and lipids for two years to see how people’s body systems aged.
Researchers believe that by identifying the geotype, people will be empowered to seek the best preventive health care for them, whether that means exercising more to avoid age-related metabolic disorders or limiting alcohol consumption to prevent liver disease. .
Researchers at Stanford University set out to determine how individuals age at a molecular level over time in one of the only studies of its kind to follow the same subjects and the ways their bodies change over time.
Dr. Michael Snyder, chair of genetics at Stanford University School of Medicine and lead author of the ageotyping report, said, “Our study captures a much more complete view of how we age by studying a broad range of molecules and taking multiple samples over the years. of each participant.
“We can see clear patterns of how individuals experience aging at the molecular level, and there is quite a difference.”
They were able to identify four main biological pathways that could explain why some parts of people’s bodies deteriorate faster than others and how they can take preventive measures earlier in their lives.
The team followed 43 healthy men and women aged 34 to 68 for two years. The researchers sampled feces, blood, genetic material, microbes, proteins and other byproducts of metabolic processes during at least five monitoring visits and tracked the levels of biological molecules over time.
By tracking how the samples changed over time, the team identified 608 molecules that could be used to predict what might contribute to age-related health problems.
A person whose geotype is metabolic has a greater likelihood as they age of experiencing health problems that affect their metabolism, a finely tuned system of chemical reactions in the body that transforms food into fuel for many biological processes in the body.
A metabolic geotype would be more likely to have problems controlling their blood sugar levels and would be more likely to suffer from heart failure, insulin resistance, obesity, and type 2 diabetes in the future. A metabolically aged person may have a higher chance of becoming obese in their later years, while at the same time may have the immune system of a much younger and stronger person.
An immune geotype refers to a person whose immune system is aging more rapidly than the rest of the body. Immune ageotypes accumulate more markers of inflammation throughout the body, which is a response to the body’s fight against harmful pathogens and toxic compounds such as free radicals that invade the body.
These people may also be at increased risk for autoimmune diseases caused by the immune system’s excessive response to the body’s cells, such as rheumatoid arthritis, lupus, type 1 diabetes, and multiple sclerosis.
A liver ageotype is one in which the liver ages faster than the rest of the body. Aging is already associated with worsening liver function, including reduced blood flow to the liver.
The liver is a vital organ for filtering and detoxifying blood, processing poisonous substances such as alcohol and drugs, and hundreds of other crucial life-sustaining functions. But a liver geotype will cause their liver function to deteriorate as they age, putting them at higher risk of cirrhosis and nonalcoholic fatty liver disease.
The nephrotic ageotype belongs to kidney function. The kidneys clean waste from the blood to make urine and balance the body’s fluids, sending clean blood throughout the body. Healthy kidneys also help control blood pressure.
Kidney geotypes have a higher risk of kidney disease later in life.
While people may fall into one of these geotype pathways, that doesn’t mean they don’t see aging in other parts of their body as well.
One person in the study, for example, showed signs of having a kidney geotype, but only showed minor age-related changes in other pathways. Meanwhile, another person showed signs of rapid aging in kidney and metabolic functioning pathways, but slower aging in immune and liver pathways.
The Stanford researchers’ findings, published in the journal Nature Medicine, suggested that as people better understand which biological processes are likely to break down first, they will be much more likely to improve their health by losing weight, limiting smoking and drinking. of alcohol and control of your high blood pressure and glucose levels.
Dr Snyder said: ‘The geotype is more than a label; can help people focus on health risk factors and find the areas where they are most likely to encounter problems in the future.
“Most importantly, our study shows that it is possible to improve the way we age. We’re starting to understand how that happens with behavior, but we’ll need more participants and more measurements over time to fully develop it.’