What is carnosine?

Carnosine is the simplest form of a dipeptide - i.e. the combination of two amino acids - consisting of alanine and histidine. These proteins are part of our normal diet and come mainly from animal products. The largest amounts are found in chicken, turkey and tuna. For example, a classic chicken soup could increase carnosine levels and at the same time curb the growth of viruses. However, the reason why longevity research is so interested in carnosine is different.

Throughout the animal kingdom there are several related forms of histidine-containing molecules that are said to have a similar function. Interestingly, almost all mammals have at least two of these substances in their cells. Humans, for some reason, have only one, carnosine. This exists mainly in the human brain and in our muscles.

What does carnosine do? - Small but mighty

Numerous exciting studies have already been carried out with carnosine. Scientists have found that carnosine binds harmful substances through chelation, i.e. complex formation, and thus eliminates them from the body via the urine. The assumption that carnosine serves as a buffering agent in our muscles also proved to be a scientifically tenable finding. Put simply, it acts like a sponge that absorbs the acidic end products of muscle contraction during exercise. This protects the muscles from fatigue, strengthens their function and prevents a possible loss of strength.

Carnosine also improved wound healing in experiments and attracted attention in ophthalmology by increasing visual acuity. Even these exciting findings are not the reason for the longevity hype. We will now take a look at this topic.

Carnosine as a longevity agent

The first extremely interesting finding on the subject of carnosine and longevity was that the molecule contributes to reduced telomere shortening. To reiterate: telomeres are the protective caps at the ends of chromosomes in our genome, which shorten over time. Shortened telomeres are a hallmark of ageing (here for the corresponding article).

Carnosine is also a powerful scavenger of reactive oxygen and nitrogen. These free radicals are by-products of mitochondrial activity and are partly responsible for the ageing process. A normal amount of free radicals is desirable, but as is so often the case, the dose makes the poison.

Carnosine has another longevity ace up its sleeve, however, and that has to do with Advanced Glycation Endproducts.

Advanced Glycation Endproducts (AGE)

Let's take a look at our favorite sweetener and valuable source of energy, sugar. As is generally known, too much of it is unhealthy. This is partly due to the fact that glucose is sticky. Both in the form of a lollipop and in its molecular structure.

Glucose sticks to pretty much everything it comes into contact with in the body. From proteins and fats to DNA. When glucose sticks, it creates distorted, harmful molecules that have lost their original function. In technical jargon, these molecules are called 'Advanced Glycation Endproducts' or AGE for short. This loss of activity is particularly problematic for proteins and has a negative impact on all aspects of cellular life.

What sounds quite theoretical at first can also be illustrated a little more clearly: collagen and elastin are among the most important proteins that ensure the structural integrity of our tissue. You can imagine the two molecules as a piece of fabric with interwoven fibers.

Proteins form an essential part of our skin, bones and blood vessel walls. There they adapt to natural conditions and provide strength and flexibility at the same time. Sounds paradoxical, but it is indispensable in a healthy body.

However, if you accidentally put a drop of super glue on the piece of fabric, the fibers can no longer slide over each other. Instead, their elasticity is lost and they become rigid and brittle. This is exactly what happens when we age, i.e. the superglue drops glucose onto our proteins. The beautiful smooth skin becomes wrinkled and saggy, while elastic blood vessels turn into steel pipes. The consequences are wrinkles, arteriosclerosis and high blood pressure.

The ageing formula can be derived as follows: The more AGEs you have, the older you have become.

What does carnosine have to do with AGEs?

Studies have shown that carnosine blocks about a dozen intermediate steps in the formation of AGEs. While study after study has confirmed this ability, there is even evidence that the proteins that have already been damaged and thus put out of action can be rescued.

The formation of waste products, which was originally assumed to be irreversible, appears to be reversible after all. So from the point of view of our collagenous connective tissue, we can actually turn back the clock! However, in order to understand the mechanisms behind this effect in more detail, some experiments still need to be carried out.

Intake of L-carnosine

The modern diet provides an inadequate daily intake of carnosine (only 50-250 mg, depending on the exact diet), whereas at least 500-3500 mg would be required for biological effects. As carnosine is mainly found in animal foods, there have been calls for animal-free alternatives.

Most carnosine sold today is in powder form. MoleQlar® Carnosine is naturally derived and has no animal origin. This makes the product vegan and vegetarian friendly.

Carnosine in powder form is a water-soluble molecule. This means that you don't necessarily have to take it with a meal. The most sensible and effective option is to add the powder to a glass of water and then drink it. The taste is slightly sweet, but by no means unpleasant - rather tasteless. Studies have shown that a quantity of up to one gram per day is safe.

Carnosine for eye health

So far you have learned about carnosine as an ideal supplement for athletes and as a possible longevity molecule. However, there is also the approach of using carnosine in the form of eye drops against cataracts.

A slightly different form is used here - namely N-acetylcarnosine. In this study, eye drops containing this active ingredient were able to show an improvement in visual acuity and increased clarity of the lens of the eye. But how is this possible?

One theory is that the formation of AGEs (the sticky sugar molecules) leads to a clumping of proteins in the lens. As a result, the lens becomes increasingly cloudy with age and our vision deteriorates. In several studies, carnosine was able to prevent the formation of AGEs and restore damaged proteins. This is also thought to be the main effect of N-acetylcarnosine eye drops. Whether this is also possible by ingesting carnosine through food still needs to be researched.

Carnosine as a sleep aid for autism spectrum disorder

Another, rather unusual area of application for carnosine is the support of sleep in children with autism spectrum disorders. The scientific basis is mainly provided by a study in which 43 children with autism spectrum disorder were divided into two groups. One received 500mg carnosine and the other a placebo. The carnosine group had fewer parasomnias (unwanted sleep events) than the comparison group without carnosine.

The scientists' hypothesis is that the brains of children with an autism spectrum disorder are more susceptible to oxidative stress. In cell studies, carnosine was able to protect nerve cells from damage with its antioxidant properties. The same applies to luteolin, which has also been tested in studies.

The data on its use in children with autism spectrum disorders is still rather sparse. There are indications that carnosine can improve sleep. However, it does not lead to a cure for autism spectrum disorder, as the researchers also emphasize in their paper.

Carnosine and zinc: Together against the inflammation of mucous membranes

Another area of application for carnosine is wound healing. Together with zinc, it has been shown in several studies that it can improve wound healing, particularly of mucous membranes.

In Japan, the mixture of zinc and carnosine (correct name: zinc L-carnosine) has been used for decades to treat stomach ulcers. And in this study, a zinc L-carnosine mouthwash improved wound healing after dental surgery. So can you simply mix zinc with carnosine and get the results?

Not quite, zinc-L-carnosine essentially only consists of the two molecules, but they are linked via a so-called chelate complex. The studies are also only designed for this fixed combination. It is not clear whether a separate intake of zinc and carnosine leads to the same results.

And how can zinc L-carnosine protect the mucous membranes? The molecular mode of action is actually quite sophisticated. If the mucous membranes, e.g. in our stomach or intestines, are damaged, the cells are more permeable to zinc. This mechanism allows zinc L-carnosine to reach exactly the place where it is needed most.

Several studies have already shown that zinc promotes wound healing and carnosine reduces inflammation thanks to its anti-inflammatory properties. In the studies, doses of 50-300mg zinc L-carnosine per day were classified as safe. Based on this data, zinc L-carnosine could therefore be a useful supplement for people with inflammatory bowel disease.

Conclusion on carnosine

The small dipeptide carnosine is more than just a source of protein, as shown by the many studies in a wide variety of areas. It is precisely its ability to prevent the formation of AGEs that makes carnosine a very potent longevity molecule.