Clinically Tested Ingredients, Athletes Approved

In today’s world of testosterone boosters, only science is king. If you’ve done your homework, then you’ve surely come across what works and what does not… So what have tests shown us?

In an effort to cut costs, companies often include very little of the clinically tested ingredients and ONLY pump their formula full of fillers and preservatives. In fact, many testosterone boosters doesn’t even tell you the specific amounts of ingredients, hiding behind proprietary blends.

Testosyn is NOT your ordinary testosterone support supplement! Testosyn is formulated with the right ingredients in the right amounts. Testosyn contains Fenusterols, D-Aspartic Acid, Born and even 140mg of pure saponins from two extracts. Testosyn’s featured ingredients have been the subjects of clinical trials showing the individual ingredients to increase endogenous testosterone levels, greater increase of fat loss, fat free mass, and one-repetition-maximum values for the bench press and leg press.

Increased Testosterone Can Support Increased Libido & Muscle Growth


Testosterone is the most crucial hormone for muscular development and a healthy libido. High testosterone levels may be the key to quickly increasing lean body mass and shedding unwanted body fat.

Unfortunately, the body’s normal testosterone levels may not be adequate enough to help you achieve your goals. What’s worse, as you age, natural testosterone production declines.

Testosyn is an advanced testosterone booster support that contains Boron and D-Aspartic Acid, shown in clinical tests to increase free testosterone levels. The formula delivers multiple powerful ingredients – recognized individually for their effectiveness in clinical studies!

The Science Behind Our Testosterone Optimizing Matrix

Along with one of the highest concentrations of Tribulus, Boron, D-Aspartic Acid & Fenusterol, Testosyn is formulated with 8 other powerful ingredients!

3,120mg D-Aspartic Acid: is one of two forms of aspartic acid, an endogenous amino acid. Though amino acids are known as building blocks of protein, this particular amino acid, D-aspartic acid has been shown to increase testosterone levels. In a clinical trial, supplementation of D-aspartic acid increased testosterone levels by 42%. Without the supplementation of D-aspartic acid, minimal change was observed. It was demonstrated that D-aspartic acid has a role in the regulation of the release and synthesis of testosterone.

D-Aspartic Acid is non-functional amino acid produced naturally in your body. It’s primarily found in the “hotspots” of hormone production - the testes, pituitary gland and hypothalamus.

12 days
3.12 g/10ml of sodium D-aspartate

basal level: 4.5 +/- 0.6 ng/ml
6 days: 5.2 +/- 0.7 ng/ml
12 days: 6.4 +/- 0.8 ng/ml
3 days after suspension: 5.8 +/- 0.6 ng/ml
TOTAL INCREASE after 12 days: 1.9 +/- 0.2 ng/ml

basal level: 4.6 +/- 0.5 ng/ml
6 days: 4.5 +/- 0.7 ng/ml
12 days: 4.7 +/- 0.7 ng/ml
3 days after suspension: 4.6 +/- 0.7 ng/ml
TOTAL INCREASE after 12 days: 0.1 +/- 0.2 ng/ml

300mg Tribulus Terrestris (40% saponins): This herb is known for its standardized for its saponins and protodioscin. In a six week clinical trial, those supplemented with tribulus terrestris extract saw greater increases in their lifts on the bench press, leg press, and deadlift than the group that was not supplemented with tribulus terrestris. The bench press increased by 14.4%, the leg press by 28.7%, and the deadlift by 20.9%.

6 Weeks
450 mg of a Tribulus Terrestris extract (60% steroidal saponins)

Strength Increases
Bench Press: 34.17165 +/- 7.05479 lbs
Leg Press: 264.555 +/- 1.54324 lbs
Deadlift: 95.90108 +/- 1.32277 lbs

Fenusterols: This saponin rich form of Fenugreek is a patent-pending ingredient designed to inhibit aromatase and 5-α reductase. A clinical trial showed its ability to increase endogenous testosterone levels. It also resulted in greater increase of fat loss, increase of fat free mass, and one-repetition-maximum values for the bench press and leg press than those who did not take fenugreek. Fenusterols is a fenugreek seed extract that contains 50% steroidal saponins standardized in a proprietary method to maximize its potential.

Body-Fat (%) Lost

Week 4 - Lost 0.96% +/- 0.11%
Week 4 - Week 8 - Lost 0.82% +/- 0.06%
Total - Lost 1.78 +/- 0.17%

Week 4 - Lost 0.78% +/- 0.09%
Week 4 - Week 8 - Gained 0.23% +/- 0.15%
Total - Lost 0.55% +/- 0.34%

Fat Free Mass

Week 4 - Increased 2.755778 +/- 0.595248 lbs
Week 4 - Week 8 - Increased 0.749572 +/- 0.2645547 lbs
Total - Gained 3.50535 +/- 0.3306934 lbs of fat free mass

Week 4 - 3.130564 +/- 0.0220462 lbs
Week 4 - Week 8 - 0.485017 +/- 0.462971 lbs
Total - Gained 1.63142 +/- 0.4885017 lbs of fat free mass


Bench Press - Increased 12.10338 +/- 3.50535 lbs
Leg Press - Increased 152.95672 +/- 28.946695 lbs

Bench Press - Increased 15.4324 +/- 5.29109
Leg Press - Increased 132.14508 +/- 22.663521

10mg Boron (Boron AAC): which is generally accepted as an essential element for humans, has also been shown to increase plasma in clinical research. In a clinical trial, without boron supplementation, free testosterone had minimal increases. However, with boron supplementation people were able to increase their free testosterone levels by 2.7 picograms per milliliter.

4 hr
Free Testosterone
10am: 9.45pg/ml
12pm: 9.01pg/ml
02pm: 9.81pg/ml

10am: 8.55pg/ml
12pm: 8.92pg/ml
02pm: 11.25pg/ml

Men Just Like You Are Seeing Results
Check Out What They're Saying

*Results in Testimonials are atypical and individual results may vary. Each testimonial achieved results via healthy diet and exercise and were renumerated.

You Get Results With Syntheroid

“At 47 years old, I've been weightlifting since I was a teen. Seen and used many different products, especially as I age. I recently started a new job and stopped hitting the gym for four months. Lost lots of strength and some size. Finally started working out again and thought I try a little 'help' in the form of Syntheroid, after reading about it online. After my first workout back I knew, from experience, my recovery time was expected to be 6-7 days. Well after only 4 days I was ready to hit the weights again! Seen gains in strength every work out since. After 4 weeks I'm virtually back lifting as heavy as I was when I stopped for the aforementioned 4 months. Also put on 15 pounds. You get results with Syntheroid. But you need to put hard quality time in the gym.”

Todd R.

It Works Well For Me!


Russell Gensler

Very Good Supplement!!!

“Very good supplement!!! Noticed really good improvements in strength, size, endurance and Libido... I'm very well pleased.... So is my wife!”

Marcel F.

Noticed A Definite Difference In Mood and Strength

“I have tried a number of items similar to this product with varying results. The ingredients in this are well known to promote an increase in natural testosterone production. I have been using it for 3 weeks or so now and have noticed a definite difference in mood and strength. This is not steroids by any means, but it will help out in cases where you want to increase your production due to age etc.”


I'm About To Order Another!

“I was eating horribly while working out and taking theses supplements. I didn't notice anything but better sleep and energy in the morning on 5 hours sleep routinely. Now eating better after two weeks and it does everything listed. I'm about to order another.”

C. Servio


“So far, 1 week with this product has boosted my energy, sharpened my attention and has really worked well. It has given me that extra boost needed during workouts and just in general. The product is a bit pricey through Amazon for a one month bottle, so I will be shopping around for a more cost efficient supply.”

Adam Hicks

*Results in Testimonials are atypical and individual results may vary. Each testimonial achieved results via healthy diet and exercise and were renumerated.

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Syntheroid is guaranteed to deliver results! If for ANY reason you are not satisfied, simply contact customer support for instructions on how to return your order of the one bottle you tried and any others in unused and resalable condition for your money back (minus S&H). With a guarantee like this you have virtually nothing to lose. Try Syntheroid today!

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