7-Keto

7-Keto (3-乙醯基-7-氧代-脫氫表雄酮) 是 DHEA（脫氫表雄酮）的天然代謝物。 在體內，7-酮不會以任何明顯的程度轉化為睪固酮或雌激素。 7-酮作為DHEA的下游代謝產物，是在DHEA降解過程中在體內產生的。 7 酮可以作為酮類固醇在血液中測量。

· 提高免疫系統功能 增強免疫功能

· 有助於減肥/產熱助減重

· 支持甲狀腺功能 支持甲狀腺功能

· 非雄性激素或雌激素無性荷爾蒙功能

· 增強記憶力增記憶

由於 7-Keto 是 DHEA 的下游代謝物，因此被宣傳為 DHEA 的「非雄性激素」或「雌激素」版本。 由於其所謂的生熱作用，它也被宣傳為減肥輔助劑。 動物研究表明，它可以增強生熱作用，從而可能轉化為減肥。 由於 DHEA 水平會隨著年齡的增長而下降，而酮類固醇是由 DHEA 製成的，因此所有可能受益於 DHEA 補充劑的病症也可能受益於 7-Keto。

一項設計不良的試驗顯示，25 至 55 歲成人每天服用 200 毫克的 7-酮補充劑可以增強減肥效果，幫助減少體內脂肪並影響甲狀腺激素水平。 這項為期兩個月的研究還表明，7-酮不會顯著影響血糖、睪固酮、雌二醇、肝或腎功能，但「顯著」的減肥益處更多是由於不平衡的研究設計，而不是補充劑的任何真正益處（與對照組相比，接受補充劑的組別在研究開始時明顯更重/更胖）。 另一項研究表明，每天 200 毫克 7-Keto 持續 8 週不會影響 18-49 歲男性的二氫睪固酮 (DHT)、雌二醇、皮質醇和胰島素水平。 多項動物研究表明，7-酮與其他合成代謝激素一樣，可以誘導產熱酶。 一項 7-Keto 試驗表明，它可以促進淋巴細胞中白細胞介素 2 的產生，但這項研究是在細胞（體外）而非人體中進行的。 7-酮也已在小鼠中被證明可以改善記憶（水迷宮程序）。

每天 200 毫克的 7-酮似乎是安全的。 迄今為止的兩項人體試驗尚未顯示高劑量補充劑有任何雄激素或雌激素作用。 許多關於 7-Keto 的說法都是基於培養皿研究、動物研究和細胞系研究，因此數據和研究結果不能應用於人體模型。

使用 7-Keto 作為合成代謝劑或促進減肥的科學證據相當薄弱，需要更多的研究來證實這種補充劑的任何流行說法是否確實合理。

少數人體試驗使用了 200 毫克/天的劑量，但商業補充劑通常提供約 50 毫克/天。

7-Keto (3-Acetyl-7-Oxo-dehydroepiandrosterone) is a naturally occurring metabolite of DHEA (dehydroepiandrosterone). In the body, 7-Keto is not converted into testosterone or estrogen to any appreciable degree. 7-Keto, as a downstream metabolite of DHEA, is produced in the body during the degradation of DHEA. 7 Keto can be measured in the blood as a ketosteroid. 

·  Improves immune system function 增強免疫功能

·  Aids in weight reduction / Thermogenic 助減重

·  Supports thyroid function 支持甲狀腺功能

·  Non-androgenic or estrogenic 無性荷爾蒙功能

·  Enhances memory 增記憶 

Because 7-Keto is a downstream metabolite of DHEA it is promoted as being a “non-androgenic” or “estrogenic” version of DHEA. It is also promoted as a weight loss aid for its supposed thermogenic effect. Animal studies demonstrate that it can enhance thermogenesis, which may translate into weight loss. Because DHEA levels decline as we age and ketosteroids are made from DHEA, all conditions which may benefit from DHEA supplementation, may also benefit from 7-Keto. 

7-Keto supplements, at a dose of 200mg/day in adults ~25 to 55 years of age has been shown in one poorly designed trial to enhance weight loss, aid in the reduction of body fat and effect thyroid hormone levels. This two-month study also demonstrated that 7-Keto does not significantly effect blood sugar, testosterone, estradiol, liver or kidney function, but the “significant” weight loss benefits were more do to an unbalanced study designthan to any real benefit of the supplement (the group receiving the supplement were significantly heavier/fatter at the start of the study compared to the control group). Another study showed that 200mg/day of 7-Keto for 8 weeks does not effect dihydrotestosterone (DHT), estradiol, cortisol and insulin levels in men 18-49 years of age. Several animal studies have demonstrated that 7-Keto, like other anabolic hormones, can induce thermogenic enzymes. One trial with 7-Keto demonstrated that it could bolster interleukin 2 production in lymphocytes, but this study was conducted in cells (in vitro) and not in humans. 7-Keto has also been shown in mice to improve memory (water maze procedure).

7-Keto appears to be safe in doses of 200mg per day. The two human trials to date have not shown any androgenic or estrogenic effects of high dose supplementation. Many of the claims for 7-Keto are based on petri dish studies, animal research and cell line studies, thus the data and findings cannot be carried over to the human model.

The scientific evidence for using 7-Keto as either an anabolic agent or for promoting weight loss is quite weak and more research is needed to substantiate if any of the popular claims made for this supplement are indeed justified.

The few human trials have used a 200mg/day dose – but commercial supplements typically provide about 50mg/day.