Impact of High Fat Diet on Fetal DevelopmentThursday, April 5, 2012
Regular readers of these pages are well aware of the importance of the adverse effects that environmental factors during fetal development can have on the subsequent health risks of the offspring.
This is again documented in a study in rats by Emily Hayes and colleagues from McMaster University, Hamilton, Ontario, published in the latest issue of PLoS One.
In their experiments, they compared the fetal development and pregnancy outcomes in female Sprague Dawley rats raised either on a high fat diet (HF – 45% of calories from fat) or a control diet (CON – 16% of calories from fat).
Prior to pregnancy HF-fed dams had significant increases in body fat, serum leptin and triglycerides.
In addition, the HF-fed dams exhibited altered vascular development in the placenta, as well as increased hypoxia as well as a more than 3-fold increase in fetal death and decreased neonatal survival.
As the authors surmise, altered placental vasculature in animals raised on a high-fat diet may result in reduced oxygenation of the fetal tissues contributing to premature demise and poor neonatal survival.
Certainly in humans, increased maternal obesity and weight gain are associated with a significantly increased risk to both the mother and infant, an issue that I have previously discussed.
The fact that such problems can be reproduced in experimental animal models certainly points to important biological consequences of nutrition and weight gain before and during gestation that can have important consequences for the infants.
Hayes EK, Lechowicz A, Petrik JJ, Storozhuk Y, Paez-Parent S, Dai Q, Samjoo IA, Mansell M, Gruslin A, Holloway AC, & Raha S (2012). Adverse fetal and neonatal outcomes associated with a life-long high fat diet: role of altered development of the placental vasculature. PloS one, 7 (3) PMID: 22442686
Thursday, April 5, 2012
I’m curious as to why the control would have been 16% fat? It seems quite low, considering we normally recommend 25-35%fat…
Thursday, April 5, 2012
First, to paraphrase Gilbert Ryle: rats are not humans; they are rats–a tautology which is sometimes worth remembering. At best, this rat study only hints at what may happen in human women. Hardly enough evidence to hang our hats on just yet.
Second, this post presupposes that a high-fat diet will always result in obesity, when the various high-fat iterations of low carb or paleo diets suggest otherwise.
Thursday, April 5, 2012
When it comes to animal studieus I have one reservation–when it comes to poison ivy and oak rats rabbits and many other animals are not harmed by the toxic substances within hoever that is not the case for use humans so there is a big difference is theya re realy different then us. That being said when it isn’t healthy to be overweight adding a weight increasing issue like maternity to the coumpound can be truly detriamental to either the mom or child.
However, mamuals should be compared to mamuals not rodunts
Saturday, April 7, 2012
High in what fats? Trans, saturated, polyunsaturated? It’d be helpful to know what the study focused on. If they’re treating all fats the same, then their approach is pretty erroneous. As someone else commented, other studies/diets suggest otherwise about high fat diets — but they have to be the right fats.
Wednesday, April 18, 2012
What I see in research is that there is a bizarre, surreal, unprofessional obliviousness to the fact that any intake is more-than-one-thing.
For example, you could do an experiment making people eat 3 pieces of whole grain bread per day with nothing else done, and you’d be studying fiber, and calories, and carbohydrates, and satiety, and blood sugar-slash-insulin, and lectins or other things specific to the food-element itself. It wouldn’t just be about “bread.”
Now in most studies I look at, they ply some unfortunate little creature–often, creatures that aren’t supposed to eat fats at all–with VEGETABLE fats or even worse fats. Horrible stuff that nobody with a brain would expect to be healthy anyway. So after feeding rodents hydrogenated soybean oil or something like that, there is then this announcement, paper, etc. all using titles like how “high fat” is bad for you and everyone takes this to mean, “because a mouse fared poorly on soybean oil, humans should not eat steak.” This is propaganda, more than science.
When I see a study announcing some experiment like that, I expect to see in any abstract note of the specific fats used, the specific creatures used, and the quantity/frequency involved. Any less information is simply a platform for misinformation and misunderstanding on the part of the public.
Sorry to be critical — this is a hot button apparently. I’ve only respect for you, thanks for all your awesome blog posts Dr. Sharma.