Studies In Animals Often Use Stressful Methods That Produce Invalid Results


Mar 18, 2013
USA / Europe
Back in 2012, when I first started writing about the benefits of steroids such as pregnenolone, I often got emails quoting the study below as evidence that pregnenolone and related steroids amplify instead of mitigate the stress response (HPA axis).

Neuroactive steroids modulate HPA axis activity and cerebral brain-derived neurotrophic factor (BDNF) protein levels in adult male rats. - PubMed - NCBI
"...We chose IP injection to assess neuroactive steroids effects at the central level because steroids can easily cross the blood–brain barrier due to their lipophilic nature (Baulieu, 1998)."

That same study was sent multiple times to Peat and his response always was that the results are invalid due to the stressful method of steroid administration. This response puzzled a lot of people since the study above used intraperitoneal (IP) injections as the administration method, and this happens to be one of the standards for steroid administration in animal studies. They kept asking Peat for evidence that this method is stressful but to my knowledge he never provided evidence to back his claim and this was labelled as one of the contrarian examples on pregnenolone for which Peat had no answer. However, as I mentioned on several of Danny's recent podcasts, recently I started doing my own animal studies and as such the issue of administration route of steroids came up several times. The lab performing the studies on my behalf kept insisting that IP injections should not be used and their preferred method was oral/gastric gavage or if that fails then subcutaneous injections. So, I asked the lab to send me justification for their claims and they sent me the following links below. As it turns out, IP injection is indeed considered one of the most stressful methods for chronic administration and special justifications need to be produced in order for ethical boards to approve the study design. Come to think of it, this should not really be a surprise for anybody. The human equivalent of an IP injection is having a foot-long needle inserted deep into the abdomen, having it sit there for a minute or two and then deliver the experimental chemical. And now imagine this being done on a daily basis for several months! People who have had repeated abdominal injections for rabies (a procedure very similar to IP injections) can tell you it's brutally painful, and some of them even develop anxiety disorders after the experience. So, no wonder rodents and other animals undergoing chronic IP injections with any chemical often respond with HPA overactivation, which usually invalidates the conclusions the study reached about the studied chemical(s). So, the moral of the story is (once again) that reading abstracts is next to useless and the key to understanding a study lies in reading the "Materials & Methods" section.

[21] Refining procedures for the administration of substances. Report of the BVAAWF/FRAME/RSPCA/UFAW Joint Working Group on Refinement. British Veterina... - PubMed - NCBI
Neurochemical, Behavioral, and Neurogenic Validation of a Hyposerotonergic Animal Model by Voluntary Oral Consumption of para-Chlorophenylalanine. - PubMed - NCBI

"...PCPA has proved useful after intraperitoneal (i.p.) treatments lasting from 2-5 days 16–18 to 4-8 weeks. Nevertheless, repeated i.p. administration is a mildly aversive procedure that can cause cumulative irritant effect[19]. Certainly, noxious stimuli like i.p. injections are perceived as localized and sharp pain given that the parietal peritoneum receives innervation by both somatic and visceral afferent nerves[20]. Although injections are done by experienced and trained professionals, needle damage, and potentially injections into abdominal organs cannot be disregarded[21]. According to the FELASA Working group on Severity classification, the severity of a procedure is determined by the degree of pain, suffering, distress or lasting harm expected to be experienced by an individual animal during the course of the procedure22. Whereas single parenteral injections are considered as mild, techniques like repeated i.p. injections in which animals are likely to experience long-lasting mild pain, correspond to the moderate category[23]. Indeed, ethical committees require rigorousjustification for repeated i.p. injections[21]. For these reasons, and in order to refine common protocols used in mice, we designed a protocol to replace i.p. injections for voluntary oral consumption of PCPA in mice."


Oct 3, 2016
Thankyou for addressing this, ive been doing alot if research lately on pubmed and im just starting to realize more and more that alot of these groups have a biased to a specific outcome, and they will never come out and actually say what they mean its like having to solve a puzzle on your own,

But im noticing now related to what you said that when i read up on the actual methods in which these studies are conducted, usually theyre never designed in the best way so kudos to you for posting this actually addressing this! Similar to what you and Danny have mentioned how blood tests can be inaccurate if you are fasted/stressed during the test


Oct 6, 2012
For sure, rodent studies are usually very poor models for human biology. I think they are at most useful for carrying out the most basic drug safety testing and studying mechanisms at the cellular or molecular level, but in terms of overall physiology or whole-organism response to drugs, one should never just take a rodent study as evidence of how something will affect a human.
Similar threads
Thread starter Title Forum Replies Date
charlie Like night and day: Animal studies may not translate to humans if time of day is disregarded Scientific Studies 2
C Georgi’s studies Cancer, Degenerative Diseases 3
bzmazu "The Illusion of Evidence Based Medicine" Fraudulent ghostwritten Studies Breaking News 1
A Studies to convince Dr to prescribe Minocyline for depression/anxiety?? Mental Issues 0
GreekDemiGod Human studies showing androgenic benefits of SFA? Ask For Help or Advice 2
Hugh Johnson Dr. Wodarg And Dr. Yeadon Request A Stop Of All Corona Vaccination Studies Vaccines 7
R Studies Comparing Vaccination To Other Health Improvements On Tropical Islands Scientific Studies 5
B Coronavirus Was Already Circulating In 2019 Or Before, Studies Find Viruses, Parasites, Fungus, Vaccines 1
Broken man Is There A Person Who Can Help Me With Russian Studies? Ask For Help or Advice 3
R Dandelion Root May Be Androgenic (Studies) Thyroid and Hormones 9
redsun Studies On Histamine's Effects Scientific Studies 43
J Why Does Peat Say Beef Is Low PUFA? Studies Are Contrary. I Don't Get It Meat 6
T Can I Get A List Of Articles And Studies About Vaccines, Antibodies, Etc Viruses, Parasites, Fungus, Vaccines 1
A I Think This Is Why Fructose / Sugar Shows Harm In Studies Miscellaneous Health Discussions 2
N Interesting Podcast Episode With Implications On Rat Studies - Bret Weinstein Miscellaneous Health Discussions 3
ecstatichamster Many Studies Show Ideal BMI For Older People Is Fat Fat Fat Scientific Studies 76
Tristan Loscha Magnesium Retention From Metabolic-Balance Studies In Female Adolescents: Impact Of NaCl Articles & Scientific Studies 0
ScurveDream Thoughts On Politics/hormone Associations In Studies/polls? Political Talk, Alternative World Theories 49
Grapelander A Look Inside The World Of Fake Scientific Studies Scientific Studies 3
yerrag Any Suggestions As To Getting Help Understanding Convoluted English In Scientific Studies? Suggestions, Complaints, Board Glitches 8
ecstatichamster Are There Studies Showing How To Inhibit Glycolysis And Encouraging Oxidative Phosphorylation Scientific Studies 14
Broken man TUDCA- Important Peaty Substance? Some Studies To Think About Supplements 43
TheBeard Studies Say Minoxidil Is Anti-androgenic Supplements, Pharmaceutical Drugs 8
B Lipofuscin Amongst Chinese In China - Need Studies Discussing Dietary Models 9
L 2 Recent Studies On Cortisol/androgen Relationship Scientific Studies 0
T Looking For Good Compilation Of Human Studies On PUFA Health 2
B Why Is This Forum Still So Obsessed With Studies Autism 51
Cirion Studies Of Effects Of Natural PUFA's Vs. Vegetable Oils? Polyunsaturated Fats, Seed Oils 27
Grapelander Wheat Germ Oil Studies: Prevents Spontaneous Abortion - Assists Neuromuscular Disorders Scientific Studies 5
Makrosky 2018 Studies On Rhodiola Rosea Supplements 9
A Pineapple Has Power Effects-Studies-Reverses Obesity Ask For Help or Advice 6
W Epidemiological Studies On Serotonin? Scientific Studies 0
Nicolas Noyola Studies On Nerve Conduction Velocity Scientific Studies 0
Runenight201 Finding Scientific Studies Scientific Studies 4
M The Dark Side Of Serotonin Exposed By Haidut In 70 Studies Scientific Studies 28
T Erythrose, A Sugar Similar To Glucose, Which Makes Cancer Cells Respire And Therefore Die, Studies Cancer 13
T The Beljanski Approach, Dr. Beljanski And His Supplements As A Cancer Treatment (with Studies) Cancer 6
biggirlkisss Good Studies That Fasting Is Dangerous Human Ones Ask For Help or Advice 21
Badger Studies That Find Vitamins Worthless Vitamins 24
M Why Does Soy Reduce Estrogen Levels In Studies? Scientific Studies 17
biggirlkisss Pepcid Aka Famotidine Studies Ask For Help or Advice 7
W Interview & Studies For Triage Theory Scientific Studies 0
J Latest Hair Studies: Hairloss Is Caused By Immune Imbalance Hair & Nails 21
Luann What Happens During Fast PUFA Loss Studies? Scientific Studies 3
biggirlkisss Dentist Wants To Xray Anyone Have Studies That Show Digital Xrays Ask For Help or Advice 8
L Can Heavy Isotopes Increase Lifespan? Studies Of Relative Abundance In Various Organisms Reveal Chem Scientific Studies 7
Giraffe Fasting Of MIce -- Impact On Results Of Studies Scientific Studies 3
W Studies On Sucrose And Starch Scientific Studies 25
EndAllDisease Studies On Thyroid Suppression By PUFA Thyroid and Hormones 8
ecstatichamster Studies? Where Is Evidence PUFAs Are Preferentially Stored Not Burned? Science 25

Similar threads