Reposted from November 27, 2008
Tryptophan is one of eight essential amino acids in the human body. Essential amino acids are so called not because they are more important to life than the others, but because the body does not synthesize them, making it essential to include them in one’s diet in order to obtain them.
Like other amino acids, tryptophan works as a building block for proteins. Tryptophan is found in every protein including fish, steak, cheese and eggs. Tryptophan is required for the synthesis of some specific organic compounds including:
- Serotonin and melatonin (neurotransmitters)
- Niacin (vitamin B3), and
- kynurenines
Serotonin (5-hydroxytryptamine) affects mood, melatonin helps regulate sleep, and kynurenines may be useful in regulating the immune system.
A drug called tranilast, available in Japan as an allergy medication, is chemically similar to kynurenines and shows promise for the treatment of certain autoimmune diseases, including multiple sclerosis.
Turkey isn’t even unusually high in tryptophan. Many foods, such as beef or soybeans, boast higher concentrations (read more and see the table comparing Turkey Tryptophan to other foods after the break).
| Food | Protein [g/100 g of food] |
Tryptophan [g/100 g of food] |
Tryptophan/Protein [%] |
|---|---|---|---|
| egg, white, dried | 81.10 | 1.00 | 1.23 |
| spirulina, dried | 57.47 | 0.93 | 1.62 |
| cod, atlantic, dried | 62.82 | 0.70 | 1.11 |
| soybeans, raw | 36.49 | 0.59 | 1.62 |
| cheese, Parmesan | 37.90 | 0.56 | 1.47 |
| caribou | 29.77 | 0.46 | 1.55 |
| sesame seed | 17.00 | 0.37 | 2.17 |
| cheese, cheddar | 24.90 | 0.32 | 1.29 |
| sunflower seed | 17.20 | 0.30 | 1.74 |
| pork, chop | 19.27 | 0.25 | 1.27 |
| turkey | 21.89 | 0.24 | 1.11 |
| chicken | 20.85 | 0.24 | 1.14 |
| beef | 20.13 | 0.23 | 1.12 |
| salmon | 19.84 | 0.22 | 1.12 |
| lamb, chop | 18.33 | 0.21 | 1.17 |
| perch, Atlantic | 18.62 | 0.21 | 1.12 |
| egg | 12.58 | 0.17 | 1.33 |
| wheat flour, white | 10.33 | 0.13 | 1.23 |
| milk | 3.22 | 0.08 | 2.34 |
| rice, white | 7.13 | 0.08 | 1.16 |
| potatoes, russet | 2.14 | 0.02 | 0.84 |
| banana | 1.03 | 0.01 | 0.87 |
Turkey sleeping pill
In its purified form and on an empty stomach, tryptophan is a mild sleep-inducing agent and that probably led to the idea that foods containing heavy doses of the chemical cause drowsiness. While consuming tryptophan-rich foods may cause blood levels of the amino acid to rise, so many other chemicals are also present in a Thanksgiving meal that not enough tryptophan reaches the brain to have a sedative affect.
In the 1980s, the connection between tryptophan serotonin was put to the test in a form of supplements marketed as a sleep aid. Ater a massive outbreak of an autoimmune disease called eosinophilia-myalgia syndrome, the FDA banned their sale in 1991.
Tens of thousands of people became sick with flu-like symptoms and 37 died. Most of the cases were attributed to contamination at the manufacturer’s plant, but some researchers still find a connection between high-doses of tryptophan and eosinophilia-myalgia syndrome.
So why the traditional Thanksgiving nap?
The lethargy may be caused by the stressful hustle and bustle of the holidays, alcohol consumption, and the massive caloric intake of the year’s biggest feast. It takes the body a tremendous amount of energy to break down these foods. When your stomach is full, blood is directed away from other organ systems, including your nervous system. The result? You will feel the need to snooze after any big meal.
| Related Web Sites |
|
