Is the Heat Aging You Faster Than You Think?

Move to a sunny state, and age like you have smoked a pack a day. Heat may silently fast-track your biological clock.

Continuous exposure to severe heat may be silently accelerating cellular aging, placing millions at risk for chronic diseases and early decline, according to a study from the University of Southern California.

US States at Highest Risk of Accelerated Cellular Aging

In recent years, large numbers of Americans have relocated to states such as Florida, Texas, and North Carolina, attracted by favorable tax policies and pleasant temperatures. However, many of these so-called “retirement havens” are now on a frightening list of danger zones for heat-induced biological wear and tear.

Using data from 3,686 Americans aged 56 and older collected between 2010 and 2016, Dr. Eun Young Choi and her team discovered that the hotter the state, the faster inhabitants aged- internally, if not outwardly. The results were reported in the journal Science Advances (1).

Their findings revealed that extreme heat does more than scorch skin and cause sunspots. It alters our bodies’ complex chemical pathways, hastening cell breakdown- a process known as biological aging. In essence, your body may feel and function years older than the age indicated on your driver’s license.

Is Heat Exposure a Short-Term Health Hazard?

“While we don’t yet have the same level of causal evidence as we do for smoking and alcohol, the results highlight that heat exposure is not just a short-term health hazard,” said Dr. Choi.

What is Biological Aging?

Biological aging, unlike the number of candles on your birthday cake, is an indicator of cellular degradation. It determines how well your body performs and its susceptibility to sickness. People in hotter climates appear to age faster than those in cooler ones- on a molecular level.

The researchers used three cutting-edge “aging clocks”- PCPhenoAge, PCGrimAge, and DunedinPACE- to measure these undetectable modifications. PCPhenoAge predicted future health degradation, PCGrimAge estimated death risk, and DunedinPACE measured the rate of biological disintegration in real-time.

Individuals who endured more than 140 days of intense heat in a single year displayed a biological age that was up to 14 months older than their true age. Over the course of the six-year trial, people in “extreme caution” zones (90°F to 103°F) aged 2.88 years faster on average.

“The key concern with accelerated biological aging is that it reflects cumulative stress on the body, which can increase the risk of age-related diseases,” according to Dr. Choi. “Prior research has linked accelerated epigenetic aging to higher risks of cardiovascular disease, metabolic disorders, cognitive decline and even mortality.”

And, while no part of the United States was immune, the South suffered the brunt of the hardship. Residents of Louisiana and Mississippi spent more than three years in “danger-level” weather (103°F to 124°F). Large portions of Texas, Alabama, and Arkansas were not far behind.

Dr. Choi underlined that lifestyle and access to cooling infrastructure are significant factors. “We can’t simply order people to pack up and relocate to a cooler environment. “Heat exposure varies greatly, even within the same state or neighborhood,” she explained. “Two people living on the same street could have very different experiences depending on factors like air conditioning, access to cooling centers or whether they work outdoors.”

Is Any Heat Safe?

Interestingly, Dr. Choi stated that short, intentional exposures, such as saunas or hot showers, may not only be innocuous but perhaps beneficial. “Some research suggests that short-term heat exposure, such as sauna use, can have benefits for circulation and cardiovascular health,” Said Dr. Choi.

Nonetheless, she advised individuals who enjoy warmer climates to stay hydrated, seek shade, and be cautious of prolonged exposure, especially if they are elderly or have underlying medical concerns.

References:

1. Ambient outdoor heat and accelerated epigenetic aging among older adults in the US
   (DOI: 10.1126/sciadv.adr0616)

Source-Medindia