Revitalize old strength with L-threonine and enjoy a stable summer

Late summer, you beautiful in-between thing: The sun hat is ready to hand, but somehow the blanket is already there too. The days are golden, the calendar is full - but inside? It looks more like snooze mode. Your head still wants to dance, your nervous system has been mumbling “please turn it down” for a long time, and even the fifth iced coffee doesn't quite deliver what it once promised.

So if you feel a bit like a parasol in the wind - shiny on the outside, wobbly on the inside - then it's worth taking a look at what your system can now gently sort out: L-threonine. An essential amino acid that doesn't make a loud noise, but helps to restore balance and inner peace.

Find out below what makes L-threonine so special and why your late summer could perhaps be a little more relaxed with this silent companion.

What is L-threonine and what function does it perform in the body?

If the body were a stage, amino acids would be the technicians behind the scenes - never in the spotlight, but nothing works without them. L-threonine is one of nine essential amino acids that our human body cannot produce itself [1]. It is, so to speak, a VIP guest among the building blocks: urgently needed, but only available externally - through food.

This inconspicuous substance is involved in more than you might think at first glance. It is contained in structural proteins such as collagen and elastin, nourishes the mucous membranes, supports the liver and is also involved where things get really exciting: in the nervous system [2, 3]. There it is involved in the production of important neurotransmitters, i.e. messenger substances that influence mood, focus and stress management [2]. You could say that threonine is certainly not the loudest amino acid in the room - but it is one of the most versatile.

Curious about what else L-threonine can do? In our magazine you will find another article with exciting details about the amino acid: L-threonine - essential amino acid with important tasks

L-threonine and its role in the nervous system

Sometimes all it takes is one wrong word, a shrill noise or a small change of plan and suddenly you're out of calm. The body keeps running, but somehow in the wrong mode. This is where it gets exciting: the ability to switch flexibly between tension and relaxation requires not only willpower, but also biochemical prerequisites. One of these is L-threonine [4].

Together with glycine, L-tryptophan, L-glutamine and L-isoleucine, threonine forms the biochemical foundation for a stable nervous system [5]. These amino acids work like a well-coordinated ensemble: some promote regeneration, others have a calming or stabilizing effect and threonine coordinates quietly in the background. In a well-coordinated autonomic nervous system, the sympathetic and parasympathetic nervous systems harmonize like two dancers - sometimes faster, sometimes slower, but always in time. L-threonine can help to maintain this choreography - not as a star, but as an irreplaceable link [2].

When the nervous system gets out of sync

It often starts gradually: sleep becomes lighter, the carousel of thoughts faster, the tolerance limit shorter. What used to be dismissed with a shrug of the shoulders now drags your mood down. These are all signs that your sympathetic nervous system may be running in continuous operation - in other words, in a mode that is set to “action”, even when it should have long been time to call it a day.

A dysregulated nervous system can lead to exhaustion, listlessness or inner restlessness in the long term - not because you are doing something wrong, but because the system has not had a chance to rebalance itself. This is exactly where threonine comes into play. As part of the body's own rhythm regulation, threonine is involved in regulating central processes and restoring the balance between stimulus reception and stimulus processing [6]. It does not ensure rest - but it does ensure that rest is possible again.

Threonine in the diet - is the natural way enough?

Ideally, we take in L-threonine through a balanced diet. If you regularly eat foods such as beef, fish, eggs, quinoa or soybeans, you are basically on the right track. But as is the case with theory: it rarely comes into play when everyday life calls.

Although threonine is contained in many protein sources, those who eat a plant-based diet or are often under stress can easily fall short of their requirements. According to the WHO, adults should consume around 15 mg of threonine per kg of body weight per day - or around 1050 mg if you weigh 70 kg [7]. This amount can be achieved, no question - but only with sufficient protein and good planning. And this is often overtaken by life.

When dietary supplements can be useful

Anyone who thinks dietary supplements are an admission has probably never experienced how relieving they can be. Because sometimes the body doesn't need more input, but more targeted input. A high-quality capsule containing threonine can provide just that: a clean, chemically defined substance that is clearly dosed, easy to take and can be integrated into many lifestyles.

Especially in combination with other nutrients - such as magnesium or B vitamins - threonine unfolds its potential as a silent companion in challenging times [8]. The important thing is the content: no hidden fillers, no artificial flavors, but quality you can rely on. And the great thing is that taking it doesn't need a lot of staging. A glass of water, a brief moment and your body has what it needs.

The effect does not unfold overnight, but rather through processes that run quietly in the background—quietly, but sustainably. When demand is high, a good supply can be exactly the missing piece of the puzzle that makes stability possible again.

And there is another crucial factor: pay attention to the form. L-threonine should be present as a proteinogenic amino acid—in other words, in a form that the body can actually utilize. This is the only way to reap all the benefits without detours or losses.

Everyday life with more peace of mind – impulses for a stable system

When the nervous system is faltering, it is not enough to just sit still. What is needed are new impulses – small but targeted adjustments that get the system moving again without overtaxing it. L-threonine can act as a silent pacemaker – in the background, but continuously.

Six everyday ideas for new stability

Sometimes it doesn't take a radical change, just a few simple impulses to quietly restore balance. The following ideas can be integrated without effort and address exactly where things often go wrong: rhythm.

1. Start the day with a protein-rich breakfast to activate your amino acid supply first thing in the morning.
2. Reduce stimuli in the evening – switch off your smartphone, dim the lights, and consciously wind down.
3. Plan regular meals, because rhythm is also crucial for hormone balance.
4. Stay active every day without pressure – whether it's a walk, light stretching, or gentle yoga.
5. Consciously deepen your breathing to gently relieve the autonomic nervous system.
6. Incorporate L-threonine into your evening routine as a structuring impulse to end the day.

Tip: It's not about turning everything upside down, but about making small, effective adjustments that put you back on solid ground and gently support the system without overtaxing or overloading it.

FAQ – Frequently asked questions

Can I take L-threonine long term?

Yes, many people use L-threonine long term [9]. It is important to use a high-quality product and adhere to the recommended dosage.

Who might find L-threonine particularly interesting?

L-threonine can be beneficial for people who often suffer from inner restlessness or who want to strengthen their nervous system in a targeted manner – for example, during stressful phases of life, when under high pressure to perform, or when suffering from an unbalanced sleep-wake cycle.

What are the differences between threonine and tryptophan?

Tryptophan is more mood-related, while threonine is more structure-oriented. Both are essential amino acids and complement each other well.

Is L-threonine also suitable for older people?

Yes, as protein utilization decreases with age, targeted supplementation can be beneficial. It is particularly worth looking at your intake if you suffer from loss of appetite or impaired digestion.

Is L-threonine also sufficiently present in a plant-based diet?

Plant sources contain threonine, but often in lower concentrations. Therefore, supplementation may be useful for vegans.

Sources

[1] https://nutritionsource.hsph.harvard.edu/protein
[2] https://pubmed.ncbi.nlm.nih.gov/9853925
[3] https://my.clevelandclinic.org/amino-acids
[4] https://www.nature.com/pr1998580z
[5] https://www.sciencedirect.com/S0026049525001994
[6] https://www.sciencedirect.com/threonine
[7] https://pubmed.ncbi.nlm.nih.gov/11916756
[8] https://pmc.ncbi.nlm.nih.gov/PMC9786204
[9] https://pmc.ncbi.nlm.nih.gov/PMC12106564