I know there are newer versions but I still have a few bottles of 7-keto that I have yet to use.
I've read that 7-Keto has a poor oral absorption ratio. So is it useless?
is not useless you need tweak your dose "up a little"
Dosage and Administration
7-oxo-DHEA has been associated with a high degree of safety and a low incidence of side effects. One toxicological study at up to 2 g/kg orally daily found "no observable, serious, adverse effects on either male or female rats" [8]. This study, along with another, found no significant increase in the weight of vital organs such as the liver [2]. However, one study found 7-oxo-DHEA to increase liver weight in rodents (DHEA also has this effect) [16]. Monkeys have also been given up 500 mg/kg daily without any adverse effects or changes in toxicological parameters (for a 175 lb. human, this would equate to 200 times the standard oral dose of 200 mg). 1000 mg/kg was associated with vomiting and salivation, but the vomiting also occured in the same animals on days that 7-oxo-DHEA was not administered, indicating that it may not have been due to the substance [17].
In human studies, 7-oxo-DHEA has been well tolerated, with no side effects reported at 200 mg orally [7, 15, 24]. Three studies have examined the effects of 7-oxo-DHEA on endrocrinological parameters. One found no significant change in blood sugar, testosterone, estradiol, or thyroid hormones other than T3, for which there was an increase. There were also no changes in tests of liver and kidney function or vital signs [15]. The other studies, the Sulcova and Davidson studies mentioned earlier (involving 25 mg transdermally for 5 days and escalating doses to 200 mg for eight weeks respectively, both in males), found reductions in total testosterone of approximately 10%, while Davidson et al. found an increase in free (usable) testosterone of about 15%. Estradiol was also decreased over the course of the study by 66% and 8% in these studies, and the second difference was not statistically significant. Overall, the effects on endrocrinological variables were either small or inconsistent, and they always remained within normal parameters [7, 22].
The primary methods of administration for 7-oxo-DHEA are oral and transdermal Transdermal administration offers multiple advantages. It has been found to be a very effective delivery method for DHEA [20, 22]. Since the half-life after oral administration of 7-oxo-DHEA is only about two hours [24], transdermal administration offers a more sustained release. In terms of which delivery method will be more effective, theoretical arguments have been presented both ways. Since transdermal administration is less likely to reach the liver, there will be less activation of thermogenic enzymes in the liver. On the other hand, 7-oxo-DHEA is metabolized to a large extent in the liver, so transdermal administration will result in more 7-oxo-DHEA reaching other tissues.
The oral dosage recommended in the literature is 200 mg (100 mg twice daily), although some have reported using higher doses. For oral use, it would ideally be taken multiple times throughout the day. Most have used a dose around 100 mg transdermally, although it is clear that even 25 mg transdermally exerts an effect.
In conclusion, 7-oxo-DHEA is a promising agent for fat loss and offers a variety of other potential benefits. It is also safe and generally free of side effects. Further research may find that 7-oxo-DHEA shares many of the other beneficial properties of DHEA.
References
1. Arch Biochem Biophys. 2003 Apr 15;412(2):251-8. Glucocorticoids inhibit interconversion of 7-hydroxy and 7-oxo metabolites of dehydroepiandrosterone: a role for 11beta-hydroxysteroid dehydrogenases? Robinzon B, Michael KK, Ripp SL, Winters SJ, Prough RA.
2. Steroids. 2004 Feb;69(2):137-44. Antioxidant effects of dehydroepiandrosterone and 7alpha-hydroxy-dehydroepiandrosterone in the rat colon, intestine and liver. Pelissier MA, Trap C, Malewiak MI, Morfin R.
3. Drug Metab Dispos. 2004 Mar;32(3):305-13. Stereo- and regioselectivity account for the diversity of dehydroepiandrosterone (DHEA) metabolites produced by liver microsomal cytochromes P450. Miller KK, Cai J, Ripp SL, Pierce WM Jr, Rushmore TH, Prough RA.
4. Biochemistry. 2002 Apr 30;41(17):5473-82. Molecular differences caused by differentiation of 3T3-L1 preadipocytes in the presence of either dehydroepiandrosterone (DHEA) or 7-oxo-DHEA. Gomez FE, Miyazaki M, Kim YC, Marwah P, Lardy HA, Ntambi JM, Fox BG.
5. Brain Res. 2003 Apr 18;969(1-2):117-25. In vitro metabolism of dehydroepiandrosterone (DHEA) to 7alpha-hydroxy-DHEA and Delta5-androstene-3beta,17beta-diol in specific regions of the aging brain from Alzheimer's and non-demented patients. Weill-Engerer S, David JP, Sazdovitch V, Liere P, Schumacher M, Delacourte A, Baulieu EE, Akwa Y.