WHY HIGH PROTEIN LOW CARB LOW FAT DIET HELPS TO LOSE WEIGHT!!!

In my previous blog I have discussed about why long term fasting or starving is a unhealthy way of losing weight. In this blog I would like to discuss why HIGH PROTEIN LOW CARB LOW FAT DIET is a healthy way of losing weight!!

When a person follows HIGH PROTEIN LOW CARB LOW FAT DIET, low carbohydrate content in the diet will not provide sufficient glucose needed by the cells specially for red blood cells and neurons. These cells are heavily dependent on glucose for their metabolic needs. When there is no sufficient glucose available from diet this leads to low blood glucose level which decreases insulin (hypoglycemic hormone) and increases glucagon (hyperglycemic hormone).

Elevated glucagon will try to maintain the normal blood glucose level. Generally glucagon will initially breakdown glycogen stored in the liver to release glucose into blood stream. Since the person on HIGH PROTEIN LOW CARB LOW FAT DIET will have minimal glycogen stores because to maintain sufficient glycogen stores one need to consume carbohydrate rich diet. So when glycogen stores are minimal in a person who follow HIGH PROTEIN LOW CARB LOW FAT DIET so the next source of glucose for glucagon is the protein!!

Generally under prolonged fasting conditions and during starvation glucagon will breakdown skeletal muscle protein and release amino acids. Most of these amino acids will be converted to amino acid alanine and get converted glucose by a process called gluconeogenesis!! Now the point here is when a person is on HIGH PROTEIN LOW CARB LOW FAT DIET the protein required for this gluconeogenesis under the influence of glucagon will be provided by the dietary protein. This will spare skeletal muscle protein being degraded!! So dietary protein is converted glucose by gluconeogenesis in the liver and released into the blood stream which will be used by red blood cells and neurons.

Now how this will help to burn fat from adipose tissue and help to lose weight!! To make one glucose molecule from protein derived amino acid alanine liver cell needs 6 ATPs!! Liver cell will get these ATPs from the electron transport chain which will use reducing equivalents like NADH + H and FADH2. Majority of these NADH+ H and FADH2 will come from fatty acid oxidation.

When a person is on HIGH PROTEIN LOW CARB LOW FAT DIET so there is less fatty acid coming from the diet hence to meet energy needs for gluconeogenesis fatty acids from adipose tissue will be utilized. How adipose tissue will release its fatty acids stored as triglycerides? Note that under low glucose conditions glucagon that is released apart from keeping gluconeogenesis process active will also break adipose tissue (lipolysis) by activating an enzyme called hormone sensitive lipase. This enzyme breaks triglycerides in adipose tissue and release fatty acids.

Fatty acids released from adipose tissue along with the glycerol molecule will be carried to the liver and fatty acids will undergo oxidation to release acetyl CoA and reducing equivalents (NADH and FADH2). Further more acetyl CoA will undergo citric acid cycle to release more NADH and FADH2. These NADH and FADH2 will get into electron transport chain to make ATPs. The ATPs generated here will provide ATPs needed for gluconeogenesis.

In this way HIGH PROTEIN LOW CARB LOW FAT DIET will lead to increased levels of glucagon in the body which will keep gluconeogenesis and lipolysis active. Gluconeogenesis will utilize protein to make glucose and the energy needed to make this glucose by gluconeogenesis is provided by fatty acid breakdown which comes from adipose tissue.

Overall, HIGH PROTEIN LOW CARB LOW FAT DIET will break adipose tissue (white fat beneath the skin) to provide energy needed to generate glucose from dietary proteins while maintaining the skeletal muscle mass. This type of diet supplemented with fruits and vegetables will help to lose weight in a healthy way!!!

I hope this article has helped you to understand scientific reasoning why HIGH PROTEIN LOW CARB LOW FAT DIET supplemented with fruits and vegetables is an healthy way of losing weight!!! If are most welcome to leave your comments or questions.

WHY CHRONIC ALCOHOL INTAKE LEADS TO FATTY LIVER

Although consumption of alcohol leads initial sense of euphoria and well-being, but on long term use it leads to many complications. One of the initial complications associated with chronic alcohol intake is FATTY LIVER. 

One of the causes for alcohol induced fatty liver is the metabolic changes that alcohol does to hepatocytes!! Generally 85%-95% of alcohol is metabolized in the liver by alcohol dehydrogenase (ADH) enzyme to acetaldehyde (a toxic by product of alcohol. Acetaldehyde is metabolized in the mitochondria of hepatocytes by aldehyde dehydrogenase (ALDH) enzyme into acetate. Acetate is released into circulation and is taken up by extra-hepatic tissues particularly skeletal muscle. 

Both ADH and ALDH catalyzed reactions each will generate NADH+H. This increases the levels of NADH+H levels both in mitochondria and cytosol. Now what’s the big deal about it!! This is the main reason for the development of fatty liver!! 

Elevated levels of NADH+H will decrease citric acid cycle in mitochondria which leads to accumulation of acetyl CoA. Acetyl CoA gets out of mitochondria as citrate and in cytoplasm citrate is converted back to acetyl CoA. Acetyl CoA now in cytoplasm gets into fatty acid synthesis pathway leading to increased fatty acid formation. 

Fatty acids will combine with glycerol to make triacylglycerol. This fatty acid containing triacylglycerol will accumulate in the hepatocyte over a period of time leading to FATTY LIVER!! A case stem based question on the above concept. You can leave your answer as a comment below.

 

If you have any queries you are most welcome to drop me an e-mail at prakashmungli@gmail.com.

You can also check my Facebook group BIOCHEMISTRY MADE EASY for other questions posted previously. Follow the link below to access Facebook group. 

www.facebook.com/groups/biochemistrymadeeasy

FASTING AND STARVATION DOES NOT HELP FOR HEALTHY WEIGHT LOSS!!

Most of us believe that just by skipping breakfast and lunch we are going to loose weight and achieve that imaginary figure that we always want to have!!! By skipping breakfast we are basically allowing our body to get into fasting condition because of the long time gap since last dinner. This will lead to low glucose level in our blood and that makes alpha-cells of our pancreas to release glucagon.  

Glucagon will try to increase blood glucose level. So the immediate source for it is the glycogen stored in the liver!! It will break the liver glycogen to release glucose into blood stream which can be used by red blood cells and the neurons. But the glycogen can last for few hours depending on individuals glycogen reserve. The glycogen reserve can last anywhere from 12 hrs-24 hrs depending on the amount of carbohydrate diet consumed since three day prior to the fasting. Since people who use fasting as a means of loosing weight will hardly have any glycogen reserve!!! 

So when glycogen reserve is exhausted then which is the next source of glucose for glucagon???  The next source of glucose for glucagon is skeletal muscle protein!!! Surprised, yes, under fasting condition and starvation, our skeletal muscle will breakdown to release amino acids into blood stream. Amino acids will be taken up by the liver, mainly as alanine, and will be converted to glucose by GLUCONEOGENESIS!! The glucose produced will be released into blood stream which will be used mainly by red blood cells and neurons. You can observe the graph below for the time line for various metabolic events!! 

Click on the slide picture below for better visualization!!!

This process will continue for next seven days, by seven days of starvation, our body would have lost 60% of muscle mass!! At this time, body will stop breaking muscle protein and will adopt itself to use fatty acid derived products called ketone bodies. Ketone bodies will be synthesized by liver under the influence of glucagon. The source for ketone bodies is adipose tissue fatty acids present in the form of triacylglycerol. 

Triacylgllycerol breakdown from adipose tissue (lipolysis) generally begins with glycogen degradation but will be at very basal level until seven days of starvation. A week after starvation, lipolysis predominates and will produce significant amounts of ketone bodies which will flood our blood stream. Brain by this time will adopt itself to use ketone bodies but red blood cells will survive only on glucose which now comes from gluconeogenesis process from glycerol!!

So when someone is using short term fasting as a means of losing weight, they basically are losing their skeletal muscle!! So stop fasting and have low carbohydrate, low fat and high protein diet to lose weight!! 

In my next blog I will explain why low carbohydrate, low fat and high protein diet will help to lose weight!!!

You are most welcome to leave your comments or e-mail me for your queries at  prakashmungli@gmail.com