Monday, March 29, 2010

The role of fat in brain evolution

This was in a post on one of the diabetes lists I belong to, and I'm thinking this book might be a very interesting read.
I ran across this book today on Dr. Michael Eades blog, "Survival of the Fattest." Here's a description from the publishers...

"How did humans evolve larger and more sophisticated brains?

In general, evolution depends on a special combination of circumstances: part genetics, part time, and part environment. In the case of human brain evolution, the main environmental influence was adaptation to a ‘shore-based’ diet, which provided the world’s richest source of nutrition, as well as a sedentary lifestyle that promoted fat deposition. Such a diet included shellfish, fish, marsh plants, frogs, bird’s eggs, etc. Humans and, and more importantly, hominid babies started to get fat, a crucial distinction that led to the development of larger brains and to the evolution of modern humans. A larger brain is expensive to maintain and this increasing demand for energy results in, succinctly, survival of the fattest."

So if we hadn't acquired sufficient fat, who knows what we humans might have become? This is a far cry from what we usually hear!

It's an expensive book to buy, but if you are interested, you might find it in your library...


http://www.amazon.com/Survival-Fattest-Human-Brain-Evolution/dp/9812561919?ie=UTF8&s=books&qid=1269844605&sr=1-1

So what will this mean for all those fat babies that everyone thinks need to be put on diets and shouldn't be fat? Seems to me that babies need that fat to help their brains grow and develop and depriving them of their fat stores is going to stunt their brain growth and development. I don't think that is something this country needs - generations of children with smaller and less capable brains simply because some people think fat isn't aesthetically pleasing. Talk about cutting your nose off to spite your face - that's a case of epic fail right there, people.

Thursday, March 25, 2010

How Weight-Loss Surgery Reverses Type 2 Diabetes: New Study Offers Explanation

This article is another in a long line of articles that is giving (false) hope to type 2 diabetics that there will be a way to put their diabetes into remission.
I belong to a couple of diabetes lists, and this link appeared on one of them, with a few comments from members of the list saying "Yeah good news if only I could find someone who would do it & ins to cover it over the age of 65." and similar things. No concerns about future complications from that kind of surgery; in fact, one person had the comment: "If you are healthy enough to survive a hysterectomy, then a bariatric surgeon would probably do the surgery for you. The risk of dying during the bariatric surgery is the same as that for a hysterectomy. The insurance is a another story. If you qualify for disability Social Security then all it takes is a phone to call to Medicare and within 2 weeks you would be qualified. Unlike other insurance companies Medicare views obesity as an illness and treatable by surgery." That doesn't take into account the risk of dying in the first week after bariatric surgery, or the first month, let alone what any of the other complications of bariatric surgery are and how they can be much worse than any of the complications of type 2 diabetes.
How scary is it that Medicare would qualify someone over the age of 65 for bariatric surgery in 2 weeks? Doesn't sound to me like Medicare would be doing the necessary psychological evaluation, and bariatric surgeons are notorious for not caring about the psychological health of their patients, as long as those patients are healthy enough to make it out of surgery (and their insurance will pay for that surgery).

So, back to the article -
"Bariatric surgery currently is considered to be the most effective long-term treatment for human obesity and often leads to marked improvements in diabetes," said the study's lead author Peter Havel, a professor with joint appointments in the School of Veterinary Medicine and Department of Nutrition.

If bariatric surgery is the most effective long-term treatment for obesity there is, we are in a heap of shit, people, because it ain't that effective. Most "obese" people don't lose enough weight to become "overweight", let alone thin. A good percentage of those who lose weight end up regaining most or all of what they lost, and those who don't regain end up with complications that are so much worse than any of the so-called ill effects of "obesity" that they would much rather have stayed fat than have had the surgery.

"This study confirms our clinical observations that metabolic regulation -- specifically homeostasis of glucose -- occurs quickly after gastric bypass surgery," said Mohamed Ali, an associate professor of gastrointestinal surgery and a specialist in bariatric surgery at UC Davis Health System. "It's clear from the outcome that something physiologic is at work with controlling diabetes that is not related to weight loss.

And instead of trying to find out what the physiologic cause is, let's just go with modifying a functioning digestive system, because that has to be where the problem is. After all, when we mutilated a functioning digestive system, we managed to accidently put type 2 diabetes into remission for a short period of time, so maybe, if we fuck with it some more, we can extend that period of time (yeah, right, I'm not going to hold my breath on that one, folks).

In severe cases of obesity -- usually when the patient is 80 to 100 or more pounds overweight -- bariatric surgery is used to alter or reconstruct the stomach and/or the intestinal tract. In such cases, obesity is not just a weight issue but also a life-threatening health problem that often leads to type 2 diabetes, heart disease and sleep apnea.

Yeah, how many thin people have type 2 diabetes, heart disease, and sleep apnea? Why did they get it? Can't blame it on fat in their cases, so why is fat blamed when fat people get the same diseases as thin people? Logic FAIL, researchers.

Havel and colleagues set out to test a hypothesis that certain bariatric surgical procedures were successful in improving type 2 diabetes, at least in part, because the procedures increased the flux of unabsorbed nutrients to the far end of the small intestine and, in doing so, triggered increased secretion of two hormones. Those hormones -- glucagon-like peptide-1 (GLP-1) and peptide-YY (PYY) -- are known to have a role in controlling food intake and improving insulin secretion and insulin sensitivity, thereby helping to stabilize blood sugar levels.
To test the hypothesis, the researchers carried out a surgical procedure known as ileal interposition in a line of rats that were predisposed to obesity and type 2 diabetes. The rat model, developed in Havel's laboratory, was known as the UC Davis Type 2 Diabetes Mellitus (UCD-T2DM) Rat. The pathology of type 2 diabetes in these animals is more similar to type 2 diabetes in humans than other existing rodent models of the disease.

So they used rats predisposed to develop type 2 diabetes (gee, just like some people are genetically predisposed to develop type 2 diabetes). Whoever would have thought of that? (/sarcasm)

They found that the rats receiving the ileal interposition surgery developed type 2 diabetes 120 days later than did the rats in the control group. Furthermore, by the time the rats were one year old, 78 percent of the control group rats were diabetic while only 38 percent of the rats that had received the ileal interposition procedure had developed diabetes.
Havel said the delay in onset of diabetes in the rats would be similar to delaying the age of onset of diabetes by approximately 10 years in a person, which would be expected to significantly decrease the amount of time for diabetic complications to develop, and to reduce the health care costs associated with treating this costly and prevalent disease.

And do they know what the possible side effects of this surgery in humans could be? Are those side effects worth the 10-year delay in the onset of type 2 diabetes (will it be cheaper to treat the side effects or the diabetes for that 10 years)? No one knows, and I'd venture to say that no one has even considered those questions.