Isotonix® L-Tryptophan

By Isotonix®

Sold by Market America

Isotonix® L-Tryptophan

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Isotonix® L-Tryptophan

By Isotonix®

Sold by Market America


$0.88 Cashback

Single Bottle (30 Servings)

For anyone who want to promote calmness, relaxation or sleep, or simply wants to enhance their mood, Isotonix L-Tryptophan may be the answer. Unlike prescription mood stabilizers used to treat specific conditions, Isotonix L-Tryptophan is a safe...
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Product Brochure

What Makes Isotonix® L-Tryptophan Unique?

Isotonix L-Tryptophan, not to be confused with the culprit of after-Thanksgiving dinner lethargy, is an isotonic capable form of the essential amino acid, l-tryptophan. L-Tryptophan is an essential amino acid that helps maintain healthy levels of serotonin in the brain which helps regulate mood. Isotonix L-Tryptophan provides maximum results by including niacin and Vitamin B6, members of the B vitamin family, which promote the normal absorption of L-tryptophan. By supplementing with L-tryptophan, healthy levels of serotonin in the brain will help enhance mood and support sleep. Bring out the happier you with Isotonix L-Tryptophan!*

Tryptophan, an essential amino acid, promotes normal levels of serotonin, one of the key brain chemicals involved in regulating mood and (a neurohormone) . In the body, tryptophan is converted into , which then can be converted into serotonin (a powerful neurotransmitter in the brain). The body cannot naturally produce this amino acid; therefore, it must be a part of the diet or ingested through supplementation. Tryptophan is a component of many animal and plant proteins. Food sources of tryptophan are dairy products, beef, poultry, barley, brown rice, fish, soybeans and peanuts.*

Isotonix L-Tryptophan is an isotonic-capable supplement and bears the same chemical resemblance of the body’s blood, plasma and tears. All fluids in the body have a certain concentration, referred to as osmotic pressure. The body’s common osmotic pressure, which is isotonic, allows consistent maintenance of body tissues. In order for a substance to be absorbed and used in the body’s metabolism, it must be in an isotonic state.

Isotonix dietary supplements are delivered in an isotonic solution. This means that the body has less work to do to obtain maximum absorption of the nutrients. The isotonic state of the suspension allows nutrients to pass directly into the small intestine and rapidly absorb into the bloodstream. With Isotonix products, little nutritive value is lost, making the absorption of nutrients highly efficient while delivering maximum results.

Related terms: Isotonix L-Tryptophan, serotonin, sleep aid, Isotonix, isotonic, sleep, relax, mood, tryptophan, l-tryptophan, 5-HTP, brain, amino acid, Tryptopure™, melatonin.

*These statements have not been evaluated by the Food and Drug Administration. This product(s) is not intended to diagnose, treat, cure or prevent any disease.


Primary Benefits of Isotonix® L-Tryptophan*:

· Promotes mental clarity and understanding of everyday situations

· May help support healthy perceptions and reactions in daily and stressful situations

· Helps enhance and stabilize mood

· May help promote calmness and relaxation

· Helps promote healthy control of feelings and perceptions

· Helps maintain healthy levels of serotonin

· May help enhance mental focus and memory

· May help support a normal sleep cycle

· Promotes sleep


Key Ingredients of Isotonix® L-Tryptophan:

L-Tryptophan (Tryptopure™): 500 mg is an essential amino acid that promotes the normal synthesis and structure of proteins. In the body, L-tryptophan is converted into niacin (vitamin B3) and serotonin, a neurotransmitter which promotes the body’s ability to regulate anger, aggression, mood and sleep. By supplementing with Isotonix L-Tryptophan , serotonin production can be supported, which will promote sleep and enhance mood.*

The metabolism of L-tryptophan to serotonin is supported in large part by the following vitamins:

Vitamin C: 75 mg is a water-soluble vitamin which acts as an antioxidant, supports normal growth and repair of body tissues, supports cardiovascular health, protects against free radicals and supports cognitive health and performance. Vitamin C supports the hydroxylation of L-tryptophan to serotonin.*

Niacin (Vitamin B3): 20 mg plays an essential role as a coenzyme (NAPH/ NADPH) for about 200 enzymes which promote normal tissue respiration, synthesis of fatty acids and steroid hormones, the metabolism of carbohydrates and amino acids, and the transport of hydrogen. When niacin levels are low, the body can use L-tryptophan to manufacture the vitamin. To produce 1 mg of niacin, the body must use 60 mg of L-tryptophan, a process which can rapidly deplete L-tryptophan levels. When niacin levels are sufficient, L-tryptophan can be used for other needs such as retaining healthy levels of serotonin.*

Pyridoxine HCl (Vitamin B6): 6 mg promotes the normal conduction of nerve impulses, regulation of steroid hormones, catabolism of glycogen for glucose, heme synthesis, and the synthesis/metabolism of amino acids and neurotransmitters. After conversion to pyridoxal phosphate ( PLP ), vitamin B6 acts as a cofactor for many enzymatic reactions involving L-tryptophan, including L-tryptophan’s conversion to serotonin.*


Frequently Asked Questions about Isotonix® L-Tryptophan:

How do I take Isotonix L-Tryptophan?

For sleep support, take 30 minutes prior to bedtime. Pour 1-2 level, white bottle capfuls of powder into the overcap. Add water to the line on the overcap (60mL/2 fl. oz for 1 capful; 120mL/4 fl. oz. for two capfuls), stir and drink.

For mood enhancement, pour 1 level, white bottle capful of powder into the overcap. Add water to the line on the overcap (60mL/2 fl. oz for 1 capful), stir and drink.

Are there any warnings associated with taking Isotonix L-Tryptophan?

If you are currently taking monoamine oxidase inhibitors (MAOI) or other antidepressants such as Zoloft or Paxil, psychoactive or tranquilizing drugs, such as Clonopin or Valium, or pain medications such as Demerol or Ultram, you should consult your physician before using this product. If you are taking any other prescription drugs or have an ongoing medical condition, you should consult your physician before using this product. Take this supplement separately from prescription medications. Women who are pregnant or breastfeeding should not use this product. Do not drive or operate heavy machinery until you know how this product can affect you, as drowsiness may occur.

How will Isotonix L-Tryptophan affect sleeping?

Isotonix L-Tryptophan can promote sleep and support a normal sleep cycle.*

Why is Isotonix L-Tryptophan important?

Tryptophan is an essential amino acid that is the precursor for serotonin (a neurotransmitter). It can help to enhance and stabilize mood, help to promote calmness and relaxation, and may help to enhance mental focus and memory.*

What are some food sources rich in the amino acid Tryptophan besides dairy products and turkey?

Foods that are considered sources of tryptophan are dairy products, beef, poultry, barley, brown rice, fish, soybeans and peanuts.

Are there any allergens associated with Isotonix L-Tryptophan?

There are no known allergens associated with Isotonix L-Tryptophan. It is suitable for vegetarians.

What is the difference between 5-HTP and Isotonix L-Tryptophan?

5-HTP stands for 5-Hydroxytryptophan. 5-HTP is a supplement that is converted in the brain to serotonin. Tryptophan is an amino acid that converts into 5-Hydroxytryptophan which then converts into serotonin. L-Tryptophan is the basic building block of serotonin, and is a synthesized intermediate compound closer to serotonin.

When should I start to see/feel the effects Isotonix L-Tryptophan ? What should I expect?

The benefits of Isotonix L-Tryptophan should be noticeable within a day of the first serving. Please remember that everyone’s body is different, so for some it may take more or less time to notice the benefits of Isotonix L-Tryptophan. The isotonic state of the suspension allows nutrients to pass directly into the small intestine and rapidly absorb into the bloodstream.*


Scientific Studies Which Support Isotonix® L-Tryptophan:

· Bell , C., et al. Tryptophan depletion and its implications for psychiatry. British Journal of Psychiatry. 178: 399-405, 2001.

· Booij, L., et al. Acute tryptophan depletion as a model of depressive relapse. British Journal of Psychiatry. 187: 148-154, 2005.

· Monograph. L-Tryptophan. Alternative Medicine Review. 11(1): 52-56, 2006.

· Murphy, S., et al. Tryptophan supplementation induces a positive bias in the processing of emotional material in healthy female volunteers. Psychopharmacology ( Berlin ). 187(1): 121-130, 2006.

· Neumeister, A., et al. Effects of tryptophan depletion vs catecholamine depletion in patients with seasonal affective disorder in remission with light therapy. Archives of General Psychiatry. 55: 524-530, 1998.

· aan het Rot, M., et al. Social behaviour and mood in everyday life: the effects of tryptophan in quarrelsome individuals. Journal of Psychiatry and Neuroscience. 31(4): 253-262, 2006.

· Russo, S, et al. Tryptophan as a link between psychopathology and somatic states. Psychosomatic Medicine. 65: 665-671, 2003.

· South, J. L-Tryptophan, nature’s answer to Prozac®. International Antiaging Systems (IAS) Bulletin, 2007. (

· van der Veen, F., et al. Effects of acute tryptophan depletion on mood and facial emotion perception related brain activation and performance in healthy women with and without a family history of depression. Neuropsychopharmacology. 32: 216-224, 2007.

· Voderholzer, U., et al. Impact of experimentally induced serotonin deficiency by tryptophan depletion on sleep EEG in healthy subjects. Neuropsychopharmacology 18(2): 112-124, 1998.

· Cools, R., et al. Tryptophan depletion disrupts the motivational guidance of goal-directed behavior as a function of trait impulsivity. Neuropsychopharmacology. 30:1362-1373, 2005.

· Del-Ben, C., et al. Serotonergic modulation of face-emotion recognition. Brazilian Journal of Medical and Biological Research. 41(4): 263-269, 2008.

· LeMarquand, D., et al. Behavioral disinhibition induced by tryptophan depletion in nonalcoholic young men with multigenerational family histories of paternal alcoholism. American Journal of Psychiatry. 156: 1771-1779, 1999.

· Murphy, S., et al. Tryptophan supplementation induces a positive bias in the processing of emotional material in healthy female volunteers. Psychopharmacology ( Berlin ). 187(1): 121-130, 2006.

· Rubinsztein, J., et al. Acute dietary tryptophan depletion impairs maintenance of “affective set” and delayed visual recognition in healthy volunteers. Psychopharmacology. 154: 319-326, 2001.

· Griffiths , W., et al. Tryptophan and sleep in young adults. Psychophysiology. 9(3): 345-356, 1972.

· Hartmann, E.. and Spinweber, C. Sleep induced by L-tryptophan. Effect of dosages within the normal dietary intake. The Journal of Nervous and Mental Disease. 167(8): 497-499, 1979.

· Steritei, R. How to get a good night’s sleep with tryptophan. NaturDoctor. 2007. (



SHOP.COM Reviews

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Love this product!!!

Shop Consultant

on 09/22/2015

Amazing product!!! I have trouble winding down to get to sleep. Always a good night sleep after I drink Isotonix L Tryptophan 😊👍

Works Great for Anxiety/Depression

Shop Consultant

on 08/13/2015

Take it every night. Helps me sleep, relax, and keep my mood balanced. Can't go with out it!!!

Great for Helping with Stress!

Shop Consultant

on 06/09/2015

After taking L-Tryptophan everyday for two months, I have noticed a difference in my mood. I am certainly more relaxed & I'm not as quick to jump the gun, so to speak. I recommend this for anyone who has trouble sleeping or is a light sleeper like myself! I noticed that when I did take this before bed, I wouldn't be tossing and turning as much. I had a deeper quality of sleep & actually felt refreshed & ready to tackle the day in the morning! L-Tryptophan has helped me out tremendously!

Love this stuff!!!

Shop Consultant

on 05/04/2015

I have a big problem falling asleep and I resorted to taking wine before going to bed. My belly grew double the size after a week!. Didn't wanna take sleeping pills because of possible suicidal ideation as a side effect I take this product and after half an hour i start feeling the sleepy. Another great thing about it is that I feel more focused and sharp at work.

Works great to help me fall asleep.

on 01/26/2015

I have found that taking this product 30 minutes before retiring, has helped me to fall asleep fast and to rest much longer at night.