Tryptophan: The Secret to a Long and Happy Life

If you want to live a long and happy life, you need tryptophan. But why do we need it? And how do we get it? That's what we will be exploring in this article.

The Importance of Mood

Our mood has a big impact on our quality of length of life. The primary cause is obvious: if we have a positive mood, we will enjoy life more, while if we experience a low mood, we will be unhappy.

Our mood also has a significant impact on our relationships. And relationships have a big impact on longevity, more so than almost any other factor.

Our ability to maintain relationships and interact with others is predicated on the idea that we can be civil and pleasant to other people. And that all starts with mood.

The Good Mood Roadmap

Our mood is affected by many things. How recently we have eaten, for a start. We feel good when we have eaten and bad when we haven't. And the food matters, too; sugar gives quick release energy leading to a quick high followed a low.

Sleep is another big factor.

But there are also chemical factors within the body. Which is, when it comes down to it, the reason that food affects our mood. One compound, in particular, has a big effect. It's called tryptophan.

What is tryptophan?

It's an amino acid. These are the building blocks of proteins, which are the building blocks of cells, which are the building blocks of our bodies.

It's used to make serotonin.

This is significant because serotonin is used to regulate our mood. This concept is the premise behind antidepressants. Known as selective serotonin reuptake inhibitors (SSRIs), these drugs increase the levels of serotonin in our brain.

But most of us do not need drugs to do this. All we need is plenty of tryptophan in our system so that our body can manufacture all of the serotonin it needs naturally.

What are the benefits?

If we do not get enough tryptophan, our body will be unable to make the serotonin it needs.

By increasing our levels of tryptophan, we find that we can:

• Sleep better
• Have increased mood stability
• Enjoy a stronger feeling of wellbeing

What does the evidence say?

There is strong evidence that a tryptophan rich diet improves your mood. In 2001, the Cochrane Collaboration published a meta-analysis looking at 108 trials [1]. They concluded:

"Available evidence does suggest these substances are better than placebo at alleviating depression. Further studies are needed to evaluate the efficacy and safety of 5-HTP and tryptophan before their widespread use can be recommended."

Given the breadth of studies included in the analysis, and the Cochrane Collaboration's reluctance to say anything works until there is a mountain of clear evidence, this finding is significant.

Other studies support the idea that it can improve our sleep and mental health. See our round-up of tryptophan for anxiety for full details.

What about life expectancy?

The evidence is less clear for the effect it has on longevity. There have been no long-term studies on humans, but two animal studies give us a mixed picture.

In 1977, a study fed rats a tryptophan deficient diet for the first 21 days of their life, before returning them to a normal diet. These rats slightly outlived rats without the 21-day diet [2].

However, more recent research contradicts this. A 2015 study looking at worms found that tryptophan increased lifespan, but at higher doses becomes toxic [3]. They concluded:

"Supplementation of C. elegans with 18 of the 20 individual amino acids extended lifespan, but lifespan often decreased with increasing concentration suggesting hormesis."

This is true of many of the nutrients we need: our body needs vitamins and heavy metals, but at higher levels, they begin to decrease our lifespan. So, as usual, balance is the way forward.

What are good sources?

The good news is that there is a wide variety of sources. So, if you are a meat lover you can get it from white meat, or if you are a vegan, there are plenty of options on that end of the spectrum, too.

Here are ten foods that have high levels:

• Bananas
• Walnuts
• Turkey
• Sunflower seeds
• Milk
• Eggs
• Cheese
• Brown rice
• Chicken
• Fish

Should I take supplements?

Tryptophan tablets are considered a dietary supplement rather than medication.

This has the advantage that you can buy them over the counter but has the disadvantage that big pharma is thus less interested in pouring money into research. Particularly since antidepressants already seem to do the job.

Therefore, there is not a lot of research into the benefits of taking tryptophan supplements [4].

The University of Michigan has published guidance [5] suggesting that supplements are helpful for insomnia, and may be helpful for depression, OCD, and anxiety, too.

Given they are available over the counter, you can do some research yourself and try them. As over-the-counter supplements, the dosage is safe.

Research on whether they can extend your life remains missing.

Summary

Ensuring we get enough tryptophan is a key component to a long and happy life. Without it, our body will be unable to make the serotonin it needs to regulate our mood. A healthy level also seems to improve lifespan.

We can get all the tryptophan we need through eating a healthy and varied diet. Evidence on whether supplements can also play a part in this is lacking.

References

[1]: Erick H. Turner, Jennifer M. Loftis, Aaron D. Blackwell. Serotonin a la carte: Supplementation with the serotonin precursor 5-hydroxytryptophan. Pharmacology & Therapeutics (2005)

[2]: University of Michigan. L-Tryptophan. 24 May 2015. Link.

[3]: Segall P. Long-term tryptophan restriction and aging in the rat. Aktuelle Gerontol. 1977 Oct;7(10):535-8.

[4]: Edwards C, Canfield J, Copes N, Brito A, Rehan M, Lipps D, Brunquell J, Westerheide SD, Bradshaw PC. Mechanisms of amino acid-mediated lifespan extension in Caenorhabditis elegans. BMC Genet. 2015 Feb 3;16:8. doi: 10.1186/s12863-015-0167-2.

[5]: Shaw K, Turner J, Del Mar C. Tryptophan and 5-hydroxytryptophan for depression. Cochrane Database Syst Rev. 2001;(3):CD003198.