1- Are the treatments with stem cells safe?
There is no medical procedure that does not involve any risk. Clinical trials are necessary to verify that the beneficial effects of a treatment outweigh these risks. If the cells that are injected have been cultivated, they may have lost control mechanisms of their proliferation, and there is a risk of generating tumors. In these cases, tests must be performed to confirm their genetic stability. Other risks are those of infection, immune rejection or complications derived from the medical process. Before participating in a treatment, it is necessary to have guarantees that all these risks have been considered and prevented as far as possible, and that there are means to treat potential side effects that may arise.
2- Someone offers me treatments with mesenchymal stem cells extracted from my bone marrow, blood or fat. Is it true that these cells can repair any kind of damage when they are injected into my damaged tissues or organs?
Mesenchymal cells can differentiate into cartilage, bone and fat. They are also known to have beneficial effects for other cell types, and they modulate the immune response. However, there is not enough evidence that once transplanted can form other types of cells or tissues that repair damaged, apart from those mentioned.
3) I am informed that the use of stem cells isolated from my own tissues involves no risk or side effects. Is this true?
The use of cells obtained from the same patient without going through culture or other procedures reduces the chances of rejection or side effects, but does not eliminate the risks. Any transplantation of cells from one region of the body to another can cause side effects that must be anticipated and evaluated.
4) On the Internet I have found testimonies of patients whose illnesses improved after treatment with stem cells. Are these testimonies reliable?
The authors of these websites can make a selection of testimonies, making only the favorable ones appear. On the other hand, it is essential to distinguish the subjective sensation of improvement derived from the treatment (the placebo effect) of the authentic clinical improvement. This can only be established with clinical trials that include treated patients and control patients who think they are being treated (placebo group).
5) ) When can a given stem cell treatment be considered solvent and scientifically proven?
The best indicators of the effectiveness of a treatment are 1) that it has gone through a rigorous clinical trial and authorized by the competent health authorities in this regard, with adequate controls, 2) that its results have been published in scientific journals and 3) that their results have been independently reproduced by other researchers.
6) How can I find out what clinical trials of stem cell treatments are being done?
The list of clinical trials currently underway can be consulted on the International Clinical Trials Register Platform of the World Health Organization (WHO) ( as well as on the web managed by the Institute of Health (NIH) of the USA (
7) Why is it not illegal to offer a treatment with stem cells whose efficacy is not proven?
These new therapies, and the rate at which being regulated is different in different countries. For this reason in a country you may be offering a treatment that would be illegal in another country. In addition, unfortunately, there are frauds that can escape the control of the health authorities. When this happens, the need for careful information is much greater.
8) In the case of the treatment I am going to submit to, do not give me the expected result. Can I apply to enter a registered clinical trial?
No. Being subjected to this type of unregulated treatment is an exclusion criterion to participate later in a clinical trial.