This will probably be the last post, other than perhaps dumping articles over in the library, regarding "leptin spikes". And I don't normally link to and discuss abstracts, but in this case the abstract says it all. Over on Mercola's hatchet job on starch, as discussed in my previous post, Ron Rosedale MD provided that science he's supposedly bridging over into medicine to support his contention that carbs "spike" leptin. Here was the first comment addressing yours truly:
Because you do not know the science, does not mean that it doesn't exist. This is over 10 years old. There are many articles subsequently that support and verify this. "Evidence That Glucose Metabolism Regulates Leptin Secretion from Cultured Rat Adipocytes" www.ncbi.nlm.nih.gov/.../9449624 Endocrinology,1998 Feb;139(2):551-8 "We conclude that glucose transport and metabolism are important factors in the regulation of leptin expression and secretion."
His repetition of the citation later in comments is illustrative of Rosedale's debate tactics. The strategy is to (a) allude to a wealth of research supporting one's opinion, (b) cite one study that appears to support one's contention but not really, and (c) repeat as often as necessary using the same one cite, and apparently (d) hoping nobody will notice that the "many articles" and "robust evidence" has never materialized. I've called him on the in vitro study previously, and it is amazing the ease with which one can assemble a landslide of research that demolishes his claim. I'm going to leave you with this last one:
Title sounds a bit daunting, no? It's poorly worded, IMO, because it seems to imply that leptin does peak in non-diabetics in the postprandial state. Here's the abstract, and I think you'll see from the get-go why I'm bothering with it.
Leptin production by the adipocyte is acutely stimulated by insulin in vitro.
Cue the Meatloaf: Stop right there! Before you go any further ... Apparently this is what Rosedale did once he found his in vitro studies, and wants his followers to do as well. Because his 1998 paper showed just this. Only a short three years later, that would make this study a decade old (ground-breaking??), we have:
This, my friends, is Rosedale's G3P moment.In normal individuals, postprandial insulin peaks are not accompanied by corresponding changes in circulating leptin.
As if the first statement weren't definitive enough:Postprandial regulation of leptin in individuals with type 2 diabetes, to our knowledge, has not been previously examined in detail. We examined the effect of meals on circulating leptin levels in six patients with type 2 diabetes who were not treated with insulin and in seven normal individuals. After informed consent was obtained, all subjects were admitted to the General Clinical Research Center for 6 days. They consumed four meals daily (breakfast, lunch, dinner and snack). Eighteen blood samples were drawn between 7 .40 a.m. and midnight for the determination of serum leptin, insulin and glucose levels.
The rest of the abstract:Postprandial peaks were clearly identifiable for glucose and insulin levels both in normal subjects and in those with type 2 diabetes. However, no postprandial peaks of leptin levels were present.
The final sentence is not good news for a self-described diabetes expert -- internationally known! -- who says it's ultimately all about the leptin.Correlation analysis demonstrated a lack of correlation between leptin levels and the levels of glucose or insulin. We conclude that, in spite of the presence of postprandial insulin peaks, there are no acute changes in circulating leptin levels postprandially in patients with type 2 diabetes who are not on insulin therapy.
In this regard, in-vivo regulation of leptin by meals in patients with type 2 diabetes is similar to that in normal individuals.
"This is essential knowledge in designing a diet to control leptin and therefore health." Oh wait, that's Rosedale again discussing what happens in a culture dish. But Rosedale has "measured hundreds of insulin and leptin levels in people." Shouldn't he know this then from his vast clinical experience??
Apparently (again in comments on Mercola):
Posted On Nov 25, 2011
I am writing 2 books. You can now keep updated from my website, drrosedale.com. I had been helping out in India for several years. I had great times at Robert"s conferences, and I am glad that you were influenced. I am sure that Robert would have loved to hear that also. Thanks for the kind words.
Perhaps the book on the program he's designed from that "essential knowledge" is already too far down the line to completion to bring it back now. Apparently leptin spiking by carbs is integral to the diet he's designed to bridge the gap between science and medicine. Too bad he didn't look closely enough at all the groundbreaking work done this past decade or so. But don't listen to me, I'm not sporting the "Expert" badge, I'm but a "Dissenter".