Life Extension Magazine®

Man vaping in café being exposed to formaldehyde

Research Update: Protect Against Formaldehyde Exposure

Formaldehyde is a pervasive environmental toxin that may lead to dementia, diabetes, and depression. Carnosine can help neutralize these damaging effects.

Scientifically reviewed by: Dr. Heidi Yanoti, DC, in August 2023. Written by: Cynthia Grotton.

On a daily basis, we are often surrounded by the toxic chemical formaldehyde.

It is used in carpeting, wood products, automobiles, paper products, and even wrinkle-resistant clothing.1 E-cigarettes deliver a substantial concentration of formaldehyde.2

Scientists are recognizing that long-term, chronic exposure to low levels of formaldehyde poses a serious health threat. This pathology is similar to that posed by another problem: excess blood sugar.

High blood sugar and formaldehyde destroy cell structures by cross-linking the body’s proteins. When this happens as a result of high glucose levels, it is called glycation.

Emerging research shows that formaldehyde may be as destructive as excess glucose.

Formaldehyde may play a role in dementia, diabetes, and possibly depression.3 All three have been proposed to share a common cause, which is formaldehyde-induced crosslinking of the body’s proteins.

Crosslinking of the body’s proteins occurs in the presence of excess blood sugar. This causes formation of advanced glycation end-products that render portions of the body’s tissues non-functional.

Formaldehyde cross-linking and glycation are similar chemical processes. Exposure to formaldehyde may be implicated in accelerated aging.3

These destructive processes have a potential resolution: the supplement called carnosine.

What you need to know

Excess exposure to formaldehyde can increase cross-linking of cells, which results in accelerated aging and disease. In the scientific literature, Carnosine, a peptide molecule well known to have glycemic benefits, is showing it may prevent the damage caused by excess formaldehyde exposure.

Three Disorders of Aging: A Connection with Formaldehyde

Man holding head

Most physicians think of diabetes, dementia, and depression as three separate conditions that grow more common with aging. New research has proposed a fascinating possibility: that the ubiquitous environmental toxin formaldehyde interrupts the vital structure and function of proteins and DNA in our cells.

Not only that, but this same destructive formaldehyde-driven cross-linking speeds aging and raises our risk for age-related disorders,3 in a fashion similar to high blood glucose–driven glycation.

Many studies reveal associations between formaldehyde exposure and age-related problems, including glaucoma, stroke, Alzheimer’s disease, and cognitive decline.3-10 The fact that all these conditions have known links to glycation demonstrates that formaldehyde-caused cross-linking may be just as pernicious.11-14

Compounding the problem, formaldehyde has been shown to interfere with basic mitochondrial function.3,15,16 In preclinical studies, formaldehyde has been shown to contribute to memory decline and impair normal DNA function.3,10, 15-17

Since it is nearly impossible to avoid exposure to this ubiquitous toxin, the question is whether there’s a way to reduce its harmful effects.

The answer is yes, and it is found in carnosine.

Carnosine Combats Formaldehyde Effects

Carnosine (not to be confused with carnitine) has many functions in human biology. The most important function of carnosine is in protecting our proteins and DNA against deformation as a result of cross-linking.

Just as carnosine can protect against sugar-induced crosslinking (glycation), it also is now of interest for its ability to protect against formaldehyde-caused crosslinking.18

Further evidence of carnosine’s anti-crosslinking ability comes from how it neutralizes methylglyoxal,3,19,20 a byproduct of excessive blood sugar that has been associated with many of the complications of type II diabetes, including damage to eyes, brain, kidneys, and other organs.21-23

In cell cultures, carnosine delayed senescence, the cellular manifestation of aging that leads to tissue and organ failure.3,24

In addition to its ability to fight destructive cross-linking caused by formaldehyde and glucose, carnosine can inhibit the enzymes that break down neurotransmitters.25

Carnosine has been shown to react directly with formaldehyde, suppressing its ability to entangle DNA strands,18 while also stimulating mitochondrial activity.26-28

One recent animal study found that carnosine protected rats from the ill effects of acute formaldehyde inhalation.29 Elevated formaldehyde levels were found in the brains of age-accelerated lab animals,30,31 while carnosine supplementation delayed the onset of accelerated aging.31

These findings suggest that carnosine can react with and help neutralize formaldehyde while also suppressing the age-related generation of formaldehyde in the brain. Our bodies produce small amounts of toxic aldehydes as part of so-called normal metabolic process.3,17

Taken together these findings suggest that:

  • Dementia, depression, and diabetes (type II) share potential relationships to formaldehyde exposure and toxicity.
  • Carnosine directly prevents the formaldehyde- and glycation-induced cross-linking that makes our proteins and DNA dysfunctional.

These combined actions make carnosine an appealing defense against the ubiquitous presence of formaldehyde in our environments.3

Sources of Formaldehyde in Daily Living

Formaldehyde is found everywhere in our environments because it has many natural sources, such as forest fires, decomposition, and even volcanoes. 1 These are sources we cannot avoid, and generally they pose little threat.

But human sources of formaldehyde far outweigh the natural ones and can produce levels in the air that rise far above the levels considered safe (less than 10 parts per billion, or PPB).1

Humans burn fuel and produce millions of tons of emissions annually, which inevitably includes large amounts of formaldehyde. In addition, many synthetic products that we use in everyday life can give off formaldehyde into our indoor air.1

Sources of combustion known to raise indoor formaldehyde levels include cooking, heating, smoking, and even burning candles and incense. But as shown by the debacle with FEMA trailers in the aftermath of hurricane Katrina, dangerously high formaldehyde levels can come directly out of many products used in the building trade: particle-board, plywood, some fiberboards, and insulating materials.1

Other indoor sources include many textiles, paints, wallpapers, glues, adhesives, varnishes, and lacquers, as well as household cleaning products (detergents, disinfectants, softeners, carpet cleaners, and shoe products), cosmetics (liquid soaps, shampoos, nail varnishes, and nail hardeners), electronic equipment (computers and photocopiers), and other items like insecticides and paper products.1

We can avoid some sources of formaldehyde—for example, sitting near a smoker exposes one to formaldehyde levels as high as 160 PPB.1 But even simply showing up for work in an office building may expose one to levels greater than 25 PPB, according to a U.S. building assessment.1

In other words, it’s practically impossible to avoid exposure to this dangerous chemical. That means our best option is to take nutritional steps to protect ourselves from the age-accelerating effects of this environmental toxin.


Man smoking E-Cigarette

Carnosine has long been regarded as a useful dietary supplement for its anti-aging benefits. This includes fighting oxidative stress and glycation.

Evidence now indicates that carnosine can defend our tissues from formaldehyde poisoning and the age-acceleration it brings.

New research suggests that chronic, low-level formaldehyde exposure may be linked to dementia diabetes, and possibly depression. Specifically, formaldehyde can disturb neurotransmitter and mitochondrial function, and by cross-linking with our proteins and DNA, it can alter myriad critical cell functions.

Carnosine fights destructive cross-linking caused by the toxin formaldehyde as well as from glucose-induced glycation.

It’s practically impossible to avoid formaldehyde, but supplementing with carnosine offers a way to help protect against its toxic, age-accelerating effects.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.


  1. Available at: Accessed 20 November, 2017.
  2. Available at: Accessed September 17, 2018.
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