I don't think there are very many in humans, actually. Whether a study shows a benefit or not of course depends on a lot of things-- subjects, dosage, time, etc. One negative study only proves no effect for the particular parameters used. I am not really familiar with the studies, but if I were a lawyer I would make it my business to get familiar with them.
I did find this study--
1: Curr Opin Clin Nutr Metab Care. 2005 Nov;8(6):641-6.
Clinical aspects of coenzyme Q10: an update.
Littarru GP, Tiano L.
Institute of Biochemistry, Polytechnic University of Marche, Via Ranieri, Ancona, Italy.
[email protected]PURPOSE OF REVIEW: Coenzyme Q10 is administered for an ever-widening range of disorders, therefore it is timely to illustrate the latest findings with special emphasis on areas in which this therapeutic approach is completely new. These findings also give further insight into the biochemical mechanisms underlying clinical involvement of coenzyme Q10. RECENT FINDINGS: Cardiovascular properties of coenzyme Q10 have been further addressed, namely regarding myocardial protection during cardiac surgery, end-stage heart failure, pediatric cardiomyopathy and in cardiopulmonary resuscitation. The vascular aspects of coenzyme Q10 addressing the important field of endothelial function are briefly examined. The controversial issue of the statin/coenzyme Q10 relationship has been investigated in preliminary studies in which the two substances were administered simultaneously. Work on different neurological diseases, involving mitochondrial dysfunction and oxidative stress, highlights some of the neuroprotective mechanisms of coenzyme Q10. A 4-year follow-up on 10 Friedreich's Ataxia patients treated with coenzyme Q10 and vitamin E showed a substantial improvement in cardiac and skeletal muscle bioenergetics and heart function. Mitochondrial dysfunction likely plays a role in the pathophysiology of migraine as well as age-related macular degeneration and a therapy including coenzyme Q10 produced significant improvement. Finally, the effect of coenzyme Q10 was evaluated in the treatment of asthenozoospermia. SUMMARY: The latest findings highlight the beneficial role of coenzyme Q10 as coadjuvant in the treatment of syndromes, characterized by impaired mitochondrial bioenergetics and increased oxidative stress, which have a high social impact. Besides their clinical significance, these data give further insight into the biochemical mechanisms of coenzyme Q10 activity.
Publication Types:
Review
PMID: 16205466
Here is Harvard's take on it==
1: Harv Health Lett. 2005 Jun;30(8):4. Related Articles, Links
Statins and their side effects. Some evidence suggests coenzyme Q10 might help with muscle problems, but it's too early to recommend it.
PMID: 16136675
However, earlier I think I posted two different medical centers that recommend coenzyme Q10.