Also … I wanted to leave you with this blog post I had a while back … that has to do with lipogenesis …
There are continuing conversations regarding the ability of the body to convert carbohydrates into body fat, a process known as lipogenesis. Different methods provide limited outcomes in the determination of quantitative lipogenesis.
Indirect calorimetry can determine only net lipogenesis, and cannot measure the true rate of fatty acid manufacture that occurs at the same time as fat is burned.
As of 1997, the capability of humans to convert carbohydrates into fat was not known. Also, if it occurred, the anatomical site had not been clearly defined.
Studies have identified the presence of the key enzymes for fatty acid manufacture to be in both the liver and the fat tissue although the actual contribution of the individual tissues had not been measured.
Up until this time, humans were believed to manufacture fat primarily in the liver. If this were the case then that newly manufactured fat would travel to the adipose tissue where it would be stored.
It is common for humans to consume a daily diet that contains between 40%-70% carbohydrate. The body has a limited capacity to store that carbohydrate as glycogen and that metabolic pathway could become saturated.
This would result in the stimulation of the fat making pathway.
The studies have been controversial with some of the early work suggesting that the manufacture of fatty acids is no more than 2-3 grams of glucose to fatty acids per day which may increase up to 10 grams in obese.
Malnourished subjects demonstrated the ability to produce 100 grams of fat per day from glucose. Dr. Kinney found rates of formation 10-20 times higher than earlier researchers. Rates of lipogenesis averaged 85 grams of fat per day versus 1 gram in normal and 4 grams in the obese.
After four days of carbohydrate intake Dr. R.R. Wolfe found a production of fat from carbohydrate that equaled 170 grams per day. Only 2% of this fat formed in the liver and 98% formed in the fat cell.
By day four when the glycogen storage depots were fully saturated all of the glucose was probably converted to fat.
Insulin stimulates this process and the hormones glucagon and epinephrine decrease it.
In modern societies this process of the conversion of carbohydrate into fat is occurring in most people because of the consumption of a high-carbohydrate diet and the fact that they?re eating more calories than they need.
During the last 25 years people have increased the consumption of calories by approximately 600 per day.
So body fat continues to climb both because of the increased calorie consumption and reduced physical activity level plus because of the high rate by which dietary carbohydrates convert to body fat.
The pathways of fat storage and fat burning are regulated by different enzymes and stimulated by different hormonal profiles in the body. Storage and burning do not both occur at the same time.
If the body is storing fuels, then the pathway of burning begins to close down.
Therefore, high-carbohydrate diets will lead to a manufacture of a minimum of 170 grams per day. After about 3 to 4 days, body fat increases of 1 pound are to be expected.
So the arguments of some of the ?self-proclaimed experts? that humans do not manufacture fat from carbohydrate are unfounded.
As I?ve stated on numerous occasions, if one wants to be an authority he has to do more than just read one research paper. Nothing less than a collection of all the work completed in an area is required.
That includes a collection of not only all the recent work but a collection of all the work on a particular topic over time to help get an historical perspective.
Further, one needs to have extensive training to analyze and critically evaluate that which he reads.
One current day writer who is a journalist only gathers his information by calling up and speaking with researchers. Without a broad base of understanding across a large range of researchers, one will typically end up with biases and misinterpretations because he can?t work through all of the information that he receives.
Most of the current crop of writers and bloggers do not have the necessary background to perform the prerequisites I?ve established above.