What is glucosamine?

As part of longevity research, many people are concerned with keeping their bodies healthy for as long as possible. In addition to maintaining cognitive performance, muscle and general cell health, this also includes healthy joints and bones. In this article, we therefore focus on a substance that has been known for some time: glucosamine. For decades, the molecule has been the focus of research into joint pain and, more recently, longevity. But what is it really all about and is it worth taking glucosamine? We explain.

Glucosamine at a glance

Glucosamine occurs naturally in our body. The substance is a component of our joint fluid, cartilage and connective tissue. As the name suggests, glucosamine is a compound of a sugar and an amino group. However, it is not only found in our bodies as humans, but also in the shells of shellfish, in animal bones, or even in bone marrow. Glucosamine is also naturally present in some mushrooms.

In our body, the molecule serves as a precursor for the production of glycosylated proteins and fats. Glycosylation refers to the chemical reaction in which carbohydrates are combined with proteins or fats, for example.

How is glucosamine produced?

It is produced in various ways. One possibility is the extraction of glucosamine from the further processing of chitin from shellfish such as crabs, shrimps or lobsters. The production by hydrolysis (splitting) of chitin was first achieved by a German researcher in 1876.

Good to know: As many dietary supplements containing glucosamine are derived from shellfish, they may not be safe for people with a shellfish allergy. Therefore, many products carry a warning label. In this case, you can buy glucosamine of plant origin or obtained from mushrooms.

For the animal-free production of glucosamine for vegans or vegetarians, the substance is obtained, for example, from the fungus Aspergillus niger or from the fermentation of corn. So there is a possibility to take also vegan glucosamine and avoid allergic reaction to shellfish.

Glucosamine and chondroitin - is the combination worthwhile?

Glucosamine is available in various forms. The most common forms are glucosamine sulphate, glucosamine hydrochloride and N-acetylglucosamine. Of these forms, glucosamine sulphate in particular is said to have a possible effect on osteoarthritis. However, many manufacturers sell glucosamine in combination with other preparations such as chondroitin or dimethylsulfone or methylsulfonylmethane (MSM for short).

However, there is currently no solid and defensible study situation for this. The data is very sparse in this regard. However, the Swiss longevity researcher Collin Ewald is investigating the substance chondroitin with regard to a possible life-prolonging effect. More on this later.

Why and when should glucosamine be supplemented?

Glucosamine has been used for decades as a dietary supplement sold for decades. The manufacturers usually suggest that it has a positive effect on joints and knee pain. As a result, many people with joint inflammation or pain buy this product in the hope that it will alleviate the condition. The idea is based on the fact that the glucosamine is absorbed by the body and incorporated into the joint or cartilage, for example.

An older meta-study came to the conclusion that glucosamine sulphate alone or in combination with chondroitin has no pain-relieving effect in patients with osteoarthritis. Furthermore, no demonstrable effect on joint wear was observed. However, this contrasts with a more recent meta-analysis from 2020, which concluded that glucosamine sulphate at a dose of 1500 mg per day does have a cartilage-protecting effect, could reduce pain and increase mobility.

Glucosamine and osteoarthritis - a closer look

The consumer advice center points out on its website that glucosamine has shown contradictory results in the studies and that there is no connection with improved joint function - this is true for now, but it is still worth taking a closer look at the (especially more recent) studies.

First of all, we need to distinguish between two clinical pictures. Osteoarthritis - the age-related loss of cartilage and arthritis - an inflammatory joint disease. These two terms are often confused, but the distinction is very important because the disease mechanism is different!

Without delving too deeply into medicine, you can remember that the main difference between arthritis and osteoarthritis is the inflammatory response. If you look at the studies on glucosamine and osteoarthritis, it's true that the results are sometimes contradictory. On the other hand, the studies on glucosamine and arthritis are more conclusive.

For example, the researchers were able to identify a significant benefit from glucosamine supplementation in temporomandibular joint arthritis. It was important to take glucosamine for a longer period of time, in this case at least three months.

Glucosamine and longevity

In addition to the joint issue, glucosamine has been in the scientific headlines recently, particularly in relation to longevity. Back in 2014, researchers discovered a life-prolonging effect of glucosamine in the nematode Caenorhabditis elegans. The extent to which these results can be transferred to humans is not yet clear. A study from 2018 confirmed these results in the same model organism. The life-prolonging effect was attributed to the activation of autophagy was attributed to the activation of autophagy.

A recently published study from 2022 also concluded that higher glucosamine levels may increase life expectancy. An article by Dr. Collin Ewald, a leading longevity researcher at ETH Zurich, was published in the renowned journal Frontiers in Aging in 2021. In his Ewaldlab , the Swiss scientist researches the molecular mechanisms of healthy ageing. He focused his research on chondroitin and came to the conclusion that the molecule may be a suitable geroprotector. By this he means a molecule with age-protective effects.

What should I pay attention to when taking it?

It is recommended, as with all dietary supplements, to talk to appropriate professionals beforehand. Here should be avoided in any case, the substance simply uncontrolled in very high quantities to take, otherwise it could lead to side effects. In addition, people who take blood-thinning medications should consult a doctor, as there may be interactions between glucosamine and drugs from the group of vitamin K antagonists.

Good to know: The Federal Institute for Risk Assessment recommends that people with impaired glucose tolerance or manifest diabetes mellitus should also be careful when taking glucosamine. The amino sugar can make blood sugar control more difficult.

Glucosamine acts on the microbiome

The change in the microbiome is one of the hallmarks of ageing. With age, the diversity of bacteria decreases and the symbiosis develops into a dysbiosis. For this reason, the microbiome is one of the most central areas of research, as many diseases are associated with an imbalance.

In this review, glucosamine was examined for its interaction with the microbiome. The idea behind this: we only absorb about half of the glucosamine via the intestine, the rest is available to the bacteria. In preclinical studies, glucosamine supplementation was able to increase the number of potentially health-promoting bacteria , while at the same time suppressing the more harmful bacteria.

Glucosamine as an autophagy booster

The researchers attribute the potential longevity effects of glucosamine to its ability to increase autophagy. Autophagy is the cell's own recycling system, which no longer functions as efficiently in old age. Altered autophagy is therefore also one of the hallmarks of ageing.

Glucosamine activates autophagy in the body via various signaling pathways, including the mTOR pathway, in a similar way to fasting. In this context, the following is also often investigated spermidine. Improved autophagy is associated with several health benefits and this pathway is probably also responsible for the positive results in the animals.

The molecular mode of action of glucosamine may also explain why glucosamine is more effective in arthritis than in osteoarthritis. As you may remember, inflammation plays a decisive role in arthritis. Among other things, glucosamine acts via the NF-kB pathway and thus reduces the release of pro-inflammatory cytokines. This means that there are fewer messenger substances that promote inflammation.

Did you know? Fasting is also molecular. It is one of the most effective methods of activating autophagy in the body. Fasting mimetics have a similar approach. These are molecules that suggest a nutrient deficiency to the body, even though none is present. This allows you to support autophagy without fasting. In addition to glucosamine, berberine and spermidine are also considered fasting mimetics. You can get all three together in our fasting bundle.

Glucosamine and its effect on blood sugar

With regard to blood sugar and glucosamine, there are various studies that take a closer look at the interaction. First of all, a distinction must be made between people who already have a disturbed sugar metabolism(insulin resistance) (or already manifest diabetes mellitus). For these people, every extra gram of sugar a day can make management more difficult.

On the other hand, increased glucosamine intake in non-diabetics was associated with a lower incidence of diabetes. Even though this was only an observational study, over 400,000 people were included.

Another point is the question of weight gain. In some animal experiments, the supplemented mice showed a higher body weight. However, these results could not be reproduced in humans.

Conclusion

Glucosamine is a scientifically well-researched and widely sold dietary supplement. The study situation for joint and knee pain is not yet entirely clear. New large studies are tending in the direction of a demonstrable effect. In the context of longevity research, however, glucosamine could be a promising substance in the fight against ageing.

Here, too, there is still some way to go on the scientific path to discover the full potential of the molecule in various organisms. Until then, it will be exciting to see what further research will be carried out in the coming years on our ageing process and what role glucosamine will play in this. The current studies suggest great things.