http://www.ergo-log.com/olive-leaf-extract-active-thyroid-hormone.html
Olive Leaf Extract boosts concentration of active thyroid hormone
The researchers gave male rats weighing 125-150 g homemade water-based Olive Leaf Extract orally for 14 days. The maximal dose was 0.5 mg per day. That works out at 4 mg per kg bodyweight. For humans, that would be about 50 mg extract per day. That's not a lot. Drug stores sell capsules containing 150 mg Olive Leaf Extract.
In the rats that were given 500 micrograms Olive Leaf Extract, the concentration of the T3 hormone rose by a factor of 2.5. This would be enough to make people wanting to lose weight faster notice a change.
The researchers suspect that the phenols in Olive Leaf Extract make the enzyme 5'-deiodinase work harder. This enzyme converts the less active thyroid hormone T4 into the more active T3.
Source:
Phytother Res. 2002 May;16(3):286-7.
I think this one is best:
East Park Research - Olive Leaf Extract
http://eastparkresearch.com/immune-daily-health/d-lenolate-product-information/
Product Description
It is formulated based on a patented extraction process of carefully selected and analyzed olive leaves that contain Oleuropein and other therapeutic compound found in olive leaves.The product has been proven and demonstrated considerable therapeutic action against health problems, through scientific research and studies.
For more than 17 years, d-Lenolate® has helped thousands of customers improve the function of their immune systems. This supplement has been, and continues to be, tested by both U.S. and international university research teams, with results proving it to be one of the best, natural and most effective way to strengthen the immune system.
Although d-Lenolate® is the core sales product, East Park Research manufactures and distributes a line of products that utilizes the d-Lenolate® formulation as its key ingredient. The product mix contains a topical formula, cleansing bar, shampoo, conditioner, Flu-Ban®
Strengthen Your Immune System — Your Best Protection and Medicine* Your immune system is under constant attack from hordes of organisms that enter your body from the air you breathe, the food you eat, the water you drink and the things you touch. The power of the olive tree has been documented for centuries.
Scientists determined the phytochemicals contained in the tree and leaves are the source of vast disease-resistant properties, which enable the olive tree to live for thousands of years. The health benefits derived from the olive leaf continue to be extolled by both herbalists and medical science. Medical experts have discovered the wonders of a phenolic compound extracted from the olive leaves know as Oleuropein, which possesses anti-viral and anti-microbial properties.
d-Lenolate® , also known as olive leaf (Olea Europaea) extract is a formulation based on a patented extraction process of selected olive leaves that contain Oleuropein. d-Lenolate® is a natural herbal supplement you can buy without a prescription, providing the protection you need from invading microorganisms that weaken the immune system. It has been shown to strengthen the system’s own defenses, so it can eliminate the burden of toxins.
The elimination of toxins allows the immune system to bring the body chemistry back into balance. d-Lenolate® was evaluated for its effectiveness against infection by influenza virus and demonstrated early protection against influenza virus infection. Significant reports, produced by some research scientists associated with well-known domestic and international universities, further indicate d-Lenolate® and its effective components have a direct causal and documented effect on some of the worst diseases afflicting the world such as HIV, E. coli, Herpes and others.
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