Tryptophan in chocolate

9 Foods High in Tryptophan and Why You Need It

Written by WebMD Editorial Contributors

In this Article

  • Why You Need Tryptophan
  • Foods with Tryptophan

Tryptophan is an essential amino acid that cannot be produced by the human body and must be obtained through your diet, primarily from animal or plant based protein sources. Tryptophan was discovered in the early 1900s after it was isolated from casein, a protein found in milk. Its molecular structure was determined a few years later.

Tryptophan plays a role in the production of serotonin, a mood stabilizer, melatonin, which helps regulate sleep patterns, niacin or vitamin B-3, and nicotinamide also known as vitamin B-3.

Over-the-counter use of synthetic tryptophan supplements were banned in the United States starting in 1989. However, tryptophan supplements were re-introduced in 2001 and are now available.

Why You Need Tryptophan

Tryptophan has the lowest concentration in the body of any amino acid, yet, it is vital for a wide variety of metabolic functions that affect your mood, cognition, and behavior.

Tryptophan elimination experiments have shown that tryptophan has a beneficial impact on:

  • Mood
  • depression
  • Learning
  • memory skills
  • visual cognition
  • Aggression control.

Research trials have shown it to have possible benefits when treating sleep disorders, seasonal affective disorder, premenstrual discomfort, and for reducing anxiety when quitting smoking. However, there is some disagreement on these results, indicating that more research is needed.

There is a common belief that tryptophan causes drowsiness. This has been associated with the U.S. holiday, Thanksgiving, where people who celebrate it report feeling tired after eating. Studies suggest that there may be some connection. Consuming large meals stimulates the production of insulin, and insulin clears the bloodstream of all amino acids except for tryptophan. In effect, insulin clears a path that can flood the brain with tryptophan.

However, there is uncertainty as to whether tryptophan causes this drowsiness. Insulin and large amounts of carbohydrates can also cause it. Additionally, there are other foods that contain more tryptophan than turkey, however, they aren't associated with drowsiness.

Foods with Tryptophan

L-Tryptophan is an essential amino acid that cannot be synthesized by humans. It is typically found in both plant and animal based proteins. Most people consume more than double the amount that is actually needed, typically getting 900-1000 milligrams per day, while the US Recommended Daily Allowance (RDA) is 250-425 milligrams per day.

Tryptophan can be found in the following foods:

1. Milk

Whole Milk is one of the largest sources of tryptophan, including 732 milligrams per quart. 2% reduced fat milk is also a good source, coming in at 551 milligrams per quart.

2. Canned Tuna

Canned tuna is another good source of tryptophan, including 472 milligrams per ounce.

3. Turkey and Chicken

Contrary to popular beliefs, turkey is a large source of tryptophan, but it is not the largest. Light meat contains 410 milligrams per pound (raw) and dark meat contains 303 milligrams per pound. Chicken also contains high amounts of tryptophan, with light meat containing 238 milligrams per pound, and dark meat containing 256 milligrams per pound.

4. Oats

Prepared oatmeal can also be a good source of tryptophan, with 147 milligrams per cup.

5. Cheese

Though not as high in tryptophan as meat and other dairy sources, cheddar cheese contains 91 milligrams of tryptophan per ounce.

6. Nuts and Seeds

Peanuts, an example in this category, contain 65 milligrams per ounce.

7. Bread

Whole wheat bread can contain up to 19 milligrams per slice, and refined white bread can contain 22 milligrams per slice.

8. Chocolate

Chocolate can contain up to 18 milligrams of tryptophan per ounce.

9. Fruits

Some fruits can also be a good source of tryptophan. For example, a medium-sized banana contains approximately 11 milligrams of it. Additionally, a medium-sized apple contains approximately 2 milligrams of tryptophan, while a single prune contains 2 milligrams of this amino acid.

The Good, the Bad and Everything in Between – Scientific Scribbles

Regardless of what form, I think it’s pretty safe to say that chocolate is one of the greatest things on this planet. Who doesn’t enjoy chocolate?

From a young age, the notion that chocolate is poisonous to our health is drilled into us. But is it really all that bad? Let’s delve deeper.


A Mood Booster

Pinch me, I must be dreaming; there really are health benefits to eating chocolate!

If you’ve ever been feeling flat or stressed out, you may have tucked into some form of chocolate and felt your mood lift pretty quickly. This is not coincidence.

Chocolate is derived from the cacao tree, where the beans are collected and then processed. Cacao beans are rich in the amino acid tryptophan. Tryptophan stimulates the neurotransmitter serotonin, dramatically increasing the serotonin levels in our brain.

Why is serotonin relevant? Serotonin is responsible for our mood’s stability, well-being and overall happiness. The more cacao present in chocolate (i.e. dark chocolate), the more serotonin is released in our brains, hence improving our mood and long term mental health.


Wait – There Are More Positive Effects?

Trytophan is not the only thing in cacao beans that are good for our health. The beans are abundant in antioxidants called flavonoids, which are able to disarm free radicals that are able to damage cells within the body. In fact, cacao beans have been measured by scientists to be one of the greatest foods in the world at eliminating free radicals.

Flavonoids also have the ability to stimulate the production of nitric oxide in the arteries, relaxing the arteries leading to greater blood flow and lower blood pressure. This improved blood flow has been shown by scientists to benefit brain function and protect skin from sun damage. Not only that, the risk of heart disease is significantly lowered.

Not too bad for a food that’s at the top of the food pyramid.

Photo by Tetiana Bykovets on Unsplash

The Not So Good Side…

The commonly thought idea that chocolate is unhealthy unfortunately does have merit to it.

Hopefully it’s not news to anyone, but chocolate contains a lot of sugar. In just a 50g bar of Cadbury Dairy Milk Chocolate, there is 28.0 grams of sugar; there is roughly half of this in the same size Dark Chocolate bar. In comparison, the recommended daily intake of sugar for a man is 36 grams.  Exceeding this sugar threshold increases chances of heart attacks and strokes due to the extra insulin within the bloodstream.

Photo by Mathilde Langevin on Unsplash

Chocolate is also rich in fats and calories, consequently leading to a range of other health issues. The likelihood of heart failure increases, as well as the risk of obesity, diabetes, acne and high blood pressure if not eaten is small portions.


Chocolate is Best in Moderation

In its purest form, chocolate is considerably healthy. It’s not the cacao bean that makes it bad, but the over processing and the additives such as sugar that are thrown in. The greater the cacao content within the chocolate, the healthier it is. If you are a fan of dark chocolate, today is your lucky day.

The sugar present means that despite all the health benefits in dark chocolate, it can’t be eaten in unlimited amounts. Enjoy your chocolate, but just in moderation.

Sweet life

In early August, we wrote that British scientists on a sample of 13,000 people showed a relationship between the consumption of dark chocolate (namely dark - with a cocoa content of more than 45 percent) and a decrease in symptoms of depression. According to the results of the work, the conditions characteristic of depression were 70 percent less common among those who ate dark chocolate, compared with those who did not eat it at all. Of course, this is only a correlation, and based on these data, it cannot be argued that chocolate can save a person from depression. Edition N + 1 talks about the possible mechanisms that allow dark chocolate to affect our emotional state and finds out if it can be called an antidepressant.

Chocolate is one of the most popular treats of people all over the world: thanks to the Mayans and Aztecs, who fell in love with the bitter aromatic drink made from cocoa beans, the conquistadors, who were also attracted by it, and especially thanks to the Dutch chemist Konrad van Guten, who in At the beginning of the 19th century, he patented a cheap method for extracting cocoa butter from beans.

I would like to say special thanks to those who added sugar and milk to the drink, which was probably quite unpleasant for the taste buds.

We have repeatedly written about the fact that chocolate is quite good for health: scientists have proven its benefits for the cardiovascular system, and for the brain and immunity.

The positive effect on the body is explained by the presence of natural compounds of flavonoids (or rather, flavonols) in cocoa butter and other derivative products of cocoa beans. They act on the human body primarily as an antioxidant, that is, they neutralize reactive oxygen species that can damage macromolecules such as proteins and DNA.

The vast majority of studies, of course, do not conclude that chocolate is a panacea. What’s more, even studies in major peer-reviewed journals suggest that the benefits found from eating chocolate, both short-term and long-term—often statistically significant—remain rather small.

The same goes for mental health. Chocolate, with its sweetness and pleasant texture and aroma, can actually lift your mood, but it is not always clear how this works - whether we are dealing exclusively with a psychological effect, or some physiological mechanism is triggered here, triggered by those properties of chocolate, which are similar to the properties of antidepressants.

Both need to be dealt with separately, but first we need to explain why what we eat can be important for mental health at all.

Serotonin from food

Depression is known to be endogenous: sometimes it does not require any external triggers, such as the loss of a job or the death of a loved one.

At a certain point, the brain ceases to synthesize and use the neurotransmitters important for it (serotonin, dopamine and noradrenaline) that are involved in the reward system, all together or only some of them. What used to work well and make you get up in the morning, enjoy meeting friends, feel the pleasure of your favorite food, breaks down.

It is difficult to predict this breakdown, especially considering that it can appear quite suddenly, therefore even those people who do not experience daily stresses that affect the state of the central nervous system are not protected from depression.

Depression, however, can be prevented by a correct - or relatively correct - lifestyle. So, sleep hygiene, physical activity, alcohol and, of course, nutrition affect the risk of developing depression.

Chocolate is one of the foods with a high content of tryptophan, one of the aromatic alpha-amino acids. True, 200 milligrams of tryptophan per 100 grams of chocolate is actually not the highest figure, for red or black caviar it is much higher (960 and 910 milligrams per 100 grams, respectively).

The proteinogenic enantiomer (optical isomer) of tryptophan, L-tryptophan, is part of the proteins of all living organisms, and its metabolite is serotonin, the same neurotransmitter, which, among other things, is very important for the brain reward system.

Synthesizes serotonin from tryptophan through another precursor step, 5-hydroxytryptophan. This substance, also known as 5-HTP, is sold as a dietary supplement that, according to some reports, is more effective than placebo in the treatment of depression, although there has not yet been enough high-quality medical research on this subject.

An impenetrable barrier

Unlike tryptophan or 5-HTP, which enter the body in its pure form (in the form of supplements) and can really increase the level of serotonin, with the same alpha-amino acid, which enters the body with food, everything is not so simple. The fact is that tryptophan, before being synthesized into a neurotransmitter, must overcome the blood-brain barrier.

Other amino acids must overcome the same barrier, and tryptophan is far from being the main one among them: the transport system that controls the movement across the blood-brain barrier prefers other amino acids that enter the body with proteins.

Therefore, simply adding foods rich in tryptophan to food will not raise the level of serotonin in the brain. Research shows that in order for the body to have enough tryptophan for further efficient synthesis of 5-HTP and serotonin, the amount of calories coming from protein should not exceed 2-4 percent of the total energy value of the food.

Chocolate does not belong to such products, since it contains about five percent protein: this is enough for tryptophan to give way to other amino acids, and serotonin is not synthesized from it.

The same can be said about dopamine. This neurotransmitter is synthesized from the alpha amino acid phenylalanine via tyrosine synthesis or from tyrosine itself.

Both amino acids are found in food products (including chocolate), but they can cross the blood-brain barrier only in their pure form (strictly speaking, dopamine is also present in pure form in food, for example, a banana peel, but it just does not pass the barrier between the circulatory system and the brain at all).

Studies on the synthesis of dopamine (as well as its metabolite norepinephrine) from food are rather limited, but it is known, for example, that tyrosine in its pure form in a sufficiently large dosage (100 milligrams per kilogram of body weight) does not affect a person's mood in any way.

That is why it is absolutely impossible to consider chocolate as a food source of serotonin and dopamine (therefore, do not believe it if they write about it somewhere). The good news, however, is that foods do not have to directly synthesize neurotransmitters in order to have an impact on how the human brain works.

Life in chocolate

Food is one of the most important incentives for the brain's reward system, and pleasant food (that is, of course, chocolate) is also a strong incentive. In studies of eating behavior or reinforcement learning, both in humans and laboratory animals, chocolate as a stimulus is considered a so-called “appetizing food” (palatable food), which can significantly increase the activity of dopaminergic neurons.

So, in an experiment on mice, it was shown that chocolate consumption increases the release of dopamine in the nucleus accumbens - the brain structure that receives signals from dopaminergic neurons and is an important part of the reward system.

The nucleus accumbens is sometimes called the "pleasure center": the activity of this zone increases when exposed to certain drugs, during sex. In addition, this area is also subject to the influence of social approval.

An experiment on young people showed that the activity of the nucleus accumbens increases when people like their own photos. By the way, it’s about the same as when eating chocolate: from this we can conclude that the lack of attention can be compensated for by chocolate - and the nucleus accumbens will not notice any difference.

The question arises: can't chocolate be considered a drug and isn't chocolate lovers threatened by "chocoholism"?

Some studies, for example, show that former heroin addicts in compulsory treatment or behind bars experience increased cravings for sugary foods. It is therefore possible that the physiological mechanisms that cause people to experience sugar cravings and experience withdrawal symptoms may be similar.

At the same time, the opioid system is really involved in obtaining pleasure from eating: in response to sweet food, opioid peptides are released in the body, which, in turn, increase the concentration of beta-endorphins in the hypothalamus.

Curiously, this effect is reversible with naltrexone, an opioid receptor antagonist prescribed, for example, after withdrawal of opiate painkillers.

However, this effect is not exclusively associated with chocolate. Rather, it occurs with the consumption of any high-carbohydrate food, even not necessarily sweet, so the work of the body's opioid system during the consumption of chocolate is not specifically explained by its unique properties.

Therefore, it is definitely impossible to consider chocolate as a drug, even in a simplified way, just as it is impossible to assert that its effect on the human body and consciousness is comparable, for example, with the effect of taking opiates. Otherwise, the production and sale of chocolate would be regulated by law. It's good that it isn't.

Hedonists approve

Of course, the "appetizing" of any sweet food, including chocolate, depends not only on the sweet taste as such - any person would prefer to eat a piece of chocolate cake, rather than a couple of tablespoons of sugar. Moreover, with chocolate, because of its physical properties and the aromatic substances contained in it, the situation is special.

The melting point of chocolate is about 30-38 degrees Celsius, which allows it to remain solid at room temperature and melt in your mouth. The melting process is almost the main thing in the consumption of chocolate.

At this stage, alkaloids, which are part of the product, are released in large quantities, which are responsible for the bitter taste and aroma familiar to cocoa, and the resulting liquidish, slightly viscous and moderately fatty consistency gives additional orosensory stimulation.

Thanks to the combination of these factors, chocolate achieves a high hedonic rating.

By the way, this concerns more milk chocolate than dark chocolate, since milk chocolate has a little more fat and carbohydrates - namely, the combination of these nutrients in the product makes it extremely attractive.

In general, it can be concluded that chocolate, despite the fact that it can improve mood, should not be considered an antidepressant. With the consumption of chocolate, any effect similar to taking real drugs is rather short-lived and certainly not as deep.

Therefore, it is not worth relying on it if you start to feel depressed, and if you have any cause for concern, you should consult a doctor.

And be sure to remember that, despite its wonderful health benefits, pleasant texture and aroma, chocolate is just chocolate.

Elizaveta Ivtushok

Why chocolate cheers you up (and why it doesn't work for some people) Goes well: it is commonly believed that chocolate cheers up. What's the matter here?

An international team of scientists recently undertook to find out whether chocolate really affects mood. They checked the profiles of 13,000 people and found that dark chocolate drinkers had a 70% lower risk of depressive symptoms than those who did not eat it. For other varieties of delicacy, scientists have not found such a relationship. Of course, we are talking only about statistical dependence, so it cannot be said that chocolate can replace antidepressants. But perhaps it really can affect the mood. Let's try to figure out exactly how.

There are many substances in chocolate that could potentially affect human health, including the flavonoids catechin and epicatechin. They neutralize reactive oxygen species that damage DNA and proteins. Studies have repeatedly shown that catechin and epicatechin are good for the heart and blood vessels, have a beneficial effect on the immune system , increase brain activity and improve mood (at least in rats).

On this topic

But it's not that simple. Firstly, the content of flavonoids in different varieties of cocoa is strong is different from . For example, beans from Jamaica had six times less epicatechin than fruits from Costa Rica. In addition, the amount of these substances may decrease due to fermentation and roasting. To buy chocolate rich in flavonoids, you need to be well versed in manufacturers, raw materials and technologies. Ordinary consumers are unlikely to delve into this.

With the benefits of chocolate for the brain and blood vessels, everything is also ambiguous. Scientists who have conducted studies on the effect of cocoa on the cardiovascular system note that the changes are rather minor and short-lived. And nothing is known about the long-term effects of consuming cocoa and products made from it.

In addition, many studies on the beneficial effects of chocolate on the heart and brain are sponsored by the manufacturers of this product - Nestle, Mars, Cadbury. It may seem strange, but most of them show that chocolate is healthy. For example, out of 100 studies sponsored by Mars, a positive effect was revealed in 98. Independent researchers criticize the methodology of such studies.

Cocoa beans also contain other substances that, in principle, can affect the emotional state of a person - the amino acids tryptophan and tyrosine. They produce the neurotransmitters serotonin and dopamine. Increasing the level of serotonin in the brain improves mood. And dopamine causes a feeling of anticipation of pleasure and encourages people to do something potentially pleasant. Both serotonin and dopamine are involved in the reward system in the brain.

But in order to participate in the production of serotonin and dopamine, amino acids from chocolate must get into the brain, and there is a problem with this. The brain and the rest of the central nervous system are protected by a special filter that traps much of what comes with the blood. Flavonoids overcome this barrier, but tryptophan and tyrosine from cocoa or chocolate do not. In one experiment, participants took several grams of tyrosine, but their mood did not improve from this. Therefore, it is impossible to consider chocolate as a source of serotonin and dopamine.

But chocolate can influence mood indirectly. Scientists consider it the so-called appetizing food, the taste and aroma of which stimulates the production of endorphins in the brain. These substances are produced in response to stress and improve the emotional state. But it is worth noting that the production of endorphins is not associated only with eating chocolate - they are released when a person eats sweets or other carbohydrate-rich foods, such as fried potatoes or pizza.

On this topic

The nutritional value of the product does not play a big role, otherwise both milk and white chocolate would be equally popular, but they are not. It's not even about psychoactive substances, because then it would not matter what is - milk chocolate or unsweetened cocoa powder.

Research has shown that brain activity can be affected by the smell or sight of chocolate alone. The main attraction in chocolate is its taste and texture.

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