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Source Naturals L-Tryptophan 500mg, 120 Capsules

4.3 out of 5 stars 547 customer reviews
| 15 answered questions
About the Product
  • Essential amino acid that helps support mood, relaxation, and restful sleep
  • Plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response
  • Supports immune functions, as the body's precursor to the kynurenines that regulate immunity
  • Extremely pure and regularly tested to ensure the highest standards of quality
  • Promotes drowsiness and good quality sleep in cases of mild insomnia and tryptophan


Product Description

Package Quantity: 1 | Size: 120 Capsules

Dietary supplement. Mood, relaxation, sleep. The essential amino acid L-Tryptophan helps support relaxation, restful sleep, and feeling better. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-Tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-Tryptophan is extremely pure and is regularly tested to ensure the highest standards of quality. (These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.) Hypoallergenic: Contains no yeast, dairy, egg, starch, salt, preservatives, or artificial color, flavor or fragrance.

Product Details

Package Quantity: 1 | Size: 120 Capsules
  • Product Dimensions: 2.5 x 2.5 x 4.5 inches ; 4.3 ounces
  • Shipping Weight: 4.8 ounces (View shipping rates and policies)
  • Domestic Shipping: Currently, item can be shipped only within the U.S. and to APO/FPO addresses. For APO/FPO shipments, please check with the manufacturer regarding warranty and support issues.
  • International Shipping: This item is not eligible for international shipping. Learn More
  • ASIN: B000GFSVS2
  • UPC: 021078019855
  • Item model number: SN1985
  • Average Customer Review: 4.3 out of 5 stars  See all reviews (547 customer reviews)
  • Amazon Best Sellers Rank: #1,415 in Health & Personal Care (See Top 100 in Health & Personal Care)

Important Information

Safety Warning
Do not use if either tamper-evident seal is broken or missing. Keep out of the reach of children. If you are pregnant, breastfeeding, may become pregnant, or are taking medications such as SSRI's or MAOI's consult your health care professional before using this product.

Ingredients
Other Ingredients: Gelatin (Capsule), Colloidal Silicon Dioxide, and Magnesium Stearate.

Directions
1 Capsule 3 times daily, between meals and preferably with fruit juice. To support restful sleep, take 3 capsules before bed. Store in a cool, dry place.

Legal Disclaimer
These statements have not yet been evaluated by the United States Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.

Actual product packaging and materials may contain more and different information than what is shown on our website. We recommend that you do not rely solely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. Please see our full disclaimer below.

Customer Reviews

Top Customer Reviews

Verified Purchase
Source Naturals L-Tryptophan has performed miracles for me. It's an amino acid that helps build the brain's feel-good chemical, serotonin. I've used it for about 2 years after reading The Mood Cure: The 4-Step Program to Take Charge of Your Emotions--Today for its nutritional advice, upon the recommendation of this book: Protein Power: The High-Protein/Low-Carbohydrate Way to Lose Weight, Feel Fit, and Boost Your Health--in Just Weeks!.

I was shocked by the difference it made for me in the quality and quantity of my sleep. I'd spent the last year or two waking up, wide awake, at 3:30 in the morning & was unable to go back to sleep. I take 1500 mg of Tryptophan (3 500 mg capsules) and 400 mg of chelated magnesium before bed and now enjoy deep and restful sleep. [I've recently added in another supplement, melatonin; you can read more about that at the end of this review].

I find that I am more resilient, resistant to stress, & easygoing since taking tryptophan.

I experienced its incredible mood-boosting effect earlier this year after enduring a ruptured appendix. I suffered several complications & had to be put on super strong antibiotics that depleted all my B Vitamins and sent me into a quick but INTENSE bout of post-surgical depression (much like what heart bypass surgery patients experience, according to my surgeon). I spoke with my physician to get his approval, then took just 500 mg of tryptophan that afternoon and then 1500 at bedtime, as usual, and bounced back to my usual cheerful self within JUST 2 DAYS.
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Size: 120 CapsulesItem Package Quantity: 1 Verified Purchase
Man- I have got to say, HANDS DOWN, this is the ONLY natural "medicinal" remedy that has ever worked for me. 1-pill for anxiety & 3-pills to sleep. I never built a tolerance either. FIVE STARS!
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Size: 120 CapsulesItem Package Quantity: 1 Verified Purchase
Like many other of the reviews, I too was very skeptical that these capsules would provide much relief to my sleepless nights, which I had been experiencing for over a year. Taking three of these capsules before bed every night seemed to almost work from the first dose. Wow, what a difference L-Tryptophan makes! Ever since taking this, I now sleep through the night and no longer find myself waking up at 3am with my mind racing full of thoughts and anxiety. I am firm believer that these capsules really work. I am getting ready to place my second order right now!
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Size: 120 CapsulesItem Package Quantity: 1 Verified Purchase
TL;DR Version:

I'm incredibly skeptical of alternative medicine, but it works.

Long Version:

I've been wrestling with severe PTSD for years, including depression, anxiety problems, and sleep disorders. But getting treated for PTSD is difficult and I hate the side-effects of psychiatric Rx's. Still, I've bordered on major mood problems that made me desperate for something. I was willing to check myself into an institution, except my insurance provider wouldn't cover enough of the expense.

Now let me say right up front that I am a skeptic. I don't put much stock in alternative medicine, as a rule. Yeah, okay, Valerian works, opioids and certain other "herbs", but most of the effective ones are Schedule-narcs, making it irrelevant for the don't-want-to-go-to-jail type of person. But I did my research and found some medical literature supporting the use of L-Tryptophan for my symptoms, so I thought I'd give it a try. But I wasn't hoping for anything. In fact, I explicitly expected this NOT to work.

Wow, I was wrong. This works so wonderfully that I wonder when the big pharma co's are going to catch on and forced the FDA to take this off the OTC market.

Regimine:

Three capsules (500mg) first thing in the morning on an empty stomach (this is important)
Two capsules mid-day an hour before lunch.
Two capsules an hour before dinner.
I also take melatonin supplements before bed. This helps, but don't overdo it or it can be counter-productive.

Effect:

It is very subtle at first. It took me a couple of weeks before I realized that I was actually feeling fine for a change. That might not sound like a big deal, but if you're suffering with PTSD, trust me: feeling "fine" is a joy.
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Size: 120 CapsulesItem Package Quantity: 1 Verified Purchase
I rated the product as a 5 because it works. Period. I've had insomnia for years & been on many sleeping pills; most of which leave me in a stupor the next day or cause blackout periods where I have no memory of what I did after taking them. Besides, they lose their effectiveness. The Tryptophan (I take 3 caps immediately before laying down) helps me fall asleep. When I awake I feel refreshed, not hung over. I'm getting on average 6 hours of quality sleep.
Additionally, Tryptophan helps the brain produce serotonin, a neurotransmitter which acts as an anti-depressant. I've literally been able to wean myself off the antidepressant Trazadone (which I took for insomnia) by replacing it with the Tryptophan.
Other health benefits of Tryptophan include: controlling hyperactivity, alleviating stress, it aids the heart, is helpful in weight management by reducing appetite & also enhances the release of growth hormone. It is good for combating migraine headaches & may help reduce some of the effects of nicotine. A study reported in the Archives of General Psychiatry found that people with a history of Bulimia Nervosa (an Eating Disorder) experienced relapses after they took an amino acid mixture lacking Tryptophan. Additionally, a lack of both Tryptophan and the mineral magnesium may contribute to coronary artery spasms.
In 1998, the FDA banned the sale of Tryptophan after 38 deaths were reportedly linked to L-Tryptophan use in New Mexico. Subsequent research showed that it was contaminants in the Tryptophan, NOT the Tryptophan itself.
I would recommend this product to anyone looking for natural alternatives to treat either depression or insomnia.
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Source Naturals L-Tryptophan 500mg, 120 Capsules
This item: Source Naturals L-Tryptophan 500mg, 120 Capsules
Price: $18.00
Ships from and sold by Amazon.com
Want to discover more products? Check out these pages to see more: pure health restful sleep, 500 mg, relaxation pills, amino prime

Disclaimer: While we work to ensure that product information is correct, on occasion manufacturers may alter their ingredient lists. Actual product packaging and materials may contain more and/or different information than that shown on our Web site. We recommend that you do not solely rely on the information presented and that you always read labels, warnings, and directions before using or consuming a product. For additional information about a product, please contact the manufacturer. Content on this site is for reference purposes and is not intended to substitute for advice given by a physician, pharmacist, or other licensed health-care professional. You should not use this information as self-diagnosis or for treating a health problem or disease. Contact your health-care provider immediately if you suspect that you have a medical problem. Information and statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease or health condition. Amazon.com assumes no liability for inaccuracies or misstatements about products.