Whole Health Source: The Carbohydrate Hypothesis of Obesity: a Critical Examination
I hope you can see by now that the carbohydrate hypothesis of obesity is not only incorrect on a number of levels, but it may even be backward. The reason why obesity and metabolism researchers don't typically subscribe to this idea is that it is contradicted by a large body of evidence from multiple fields. I understand that people like ideas that "challenge conventional wisdom", but the fact is that obesity is a complex state and it will not be shoehorned into simplistic hypotheses.
Carbohydrate consumption per se is not behind the obesity epidemic. However, once overweight or obesity is established, carbohydrate restriction can aid fat loss in some people. The mechanism by which this occurs is not totally clear, but there is no evidence that insulin plays a causal role in this process. Carbohydrate restriction spontaneously reduces calorie intake (as does fat restriction to a lesser extent), suggesting the possibility that it alters body fat homeostasis, but there is no compelling evidence that that happens due to a hormonal influence on fat tissue itself. The brain is the primary homeostatic regulator of fat mass, just as it homeostatically regulates blood pressure, breathing rate, and body temperature.
Here is an interesting article by Ron Rosedale on insulin and longevity, old but interesting
Insulin, Leptin, Diabetes, and Aging: Not So Strange Bedfellows - Diabetes Health
and check this
Long-life Link: Gut protein ties low insulin to longevity | Biomedicine | Science News
I have not gone through these to evaluate them for quality, some will probably find holes to pick in the hypotheses, but it all adds to the knowledge base
I had some time to think about this whole thing...
Insulin is excreted into the blood after eating protein or carbohydrate, but not fat.
Fat is rarely eaten alone.
Carbs and protein are often eaten alone.
If one eats a meal containing C, blood glucose rises, the insulin helps clear the blood of excess glucose, because too much is toxic.
If someone checks their blood glucose before eating a meal of only protein, and again after, the result is almost the same. Say my blood glucose was 95, I eat a pound of lean chicken breast, then check blood glucose--it's still in the 90-100 range. But how is this possible? Insulin was secreted by my pancreas in response to the protein meal--shouldn't the insulin have made me hypoglycemic? You would think that ingesting no carbs along with an insulin surge would clear any glucose from the blood and cause low blood sugar.
So, in the absence of dietary glucose, insulin doesn't act to clear glucose from the blood. But insulin does still, presumably, act to do it's 'other stuff' like putting amino acids into cells, hormone stuff, fat stuff...
My takeaway is that circulating glucose is bad outside a narrow band and the healthy body will strive to maintain this narrow band. Dietary glucose will cause spikes in blood glucose. Insulin is a good thing. But, we don't need to eat glucose in order to get the insulin we require.
That is some good thinking. Insulin does a lot more than just the glucose thing, so that would make a lot of sense.
A lb of lean chicken breast would send my BG soaring. Just 55 g of beef protein jacked it 24 points.
Originally Posted by otzi
Same here. Fat alone has no impact, and how fatty the meat will influence its impact.
True dat! Nothing like a pound of bacon and a large cup of bulletproof coffee for breakfast to keep this harmful insulin in check…
Fat slows down insulin response an lowers the glycemic index of foods by slowing the absorption of glucose (whether it's from carbs or gluconeogenesis). Therefore, it seems logical to me that the leaner the meat/protein source, the greater the insulin response and resultant blood glucose.
Originally Posted by Artbuc
Protein: metabolism and effect on bloo... [Diabetes Educ. 1997 Nov-Dec] - PubMed - NCBI
Insulin is required for carbohydrate, fat, and protein to be metabolized. With respect to carbohydrate from a clinical standpoint, the major determinate of the glycemic response is the total amount of carbohydrate ingested rather than the source of the carbohydrate. This fact is the basic principle of carbohydrate counting for meal planning. Fat has little, if any, effect on blood glucose levels, although a high fat intake does appear to contribute to insulin resistance. Protein has a minimal effect on blood glucose levels with adequate insulin. However, with insulin deficiency, gluconeogenesis proceeds rapidly and contributes to an elevated blood glucose level. With adequate insulin, the blood glucose response in persons with diabetes would be expected to be similar to the blood glucose response in persons without diabetes. The reason why protein does not increase blood glucose levels is unclear. Several possibilities might explain the response: a slow conversion of protein to glucose, less protein being converted to glucose and released than previously thought, glucose from protein being incorporated into hepatic glycogen stores but not increasing the rate of hepatic glucose release, or because the process of gluconeogenesis from protein occurs over a period of hours and glucose can be disposed of if presented for utilization slowly and evenly over a long time period.
Best explanation yet, with graphs! Low-Carb for You: Protein Intake and Blood Glucose Levels
What happens when a person eats protein? Insulin is released in response to protein as well, enabling the amino acids to be removed from the blood and stored in the tissue. The cells don't know the insulin is there to remove amino acids from the blood, so they will take up glucose from the blood as well. To prevent hypoglycemia, the liver gradually releases glucose into the blood to replace the glucose that has been stored.