There have been great advances in the field of epigenetics, which is the study of environmental factors such as diet and toxins that can influence gene expression.
There was a longheld belief that genes had a permanent plan for our biology. We now know that some genetic markers for cancer will not necessary be “expressed” and that we can, via epigenetics therapy, effect gene expression.
For example, piperine, a nutrient compound found in black pepper, has an epigenetic effect. This means that it can change or reduce the expression of specific cancer genes, even ones that are programmed for cancer. Researchers have found that piperine may be a potential agent for the prevention and treatment of human breast cancer as it reduces HER2 overexpression.
Even though this is a new science, the research strongly indicates that individuals may benefit from its application today.
Photos: (Top) Wikipedia, (Peppercorns) Creative commons
This is the fifth of a five-part series on Metabolism.
Carbohydrate metabolism involves both anabolism and catabolism. Because your body prefers the glucose provided by dietary carbohydrates for fuel, most glucose that enter cells is catabolized or torn apart to produce energy. Very little is used for anabolism. When not enough glucose is available for fuel, the cells catabolize fatty acids next and only then amino acids.
This is why it is important to eat carbohydrates with protein; the carbohydrates will then be used for fuel and the protein will be spared and used to anabolize new protein and muscle. This is sometimes called the protein-sparing effect of carbohydrate. When only protein is eaten the cells have to catabolize it for fuel instead of making it into new protein and tissue. For this reason most protein powders used as supplements contain some carbohydrate too. That way they can be sure that the protein is used for its intended purpose.
The glucose absorbed through the intestine immediately goes into the portal system, the blood vessels that connect the intestinal blood supply directly to the liver. The liver then has first crack at the glucose absorbing up to two-thirds of it.
This is the fourth of a five-part series on Metabolism.
While the assembly line has been moving through the gut a lot has been happening in the blood. It looks the same to the naked eye but microscopically the types of message hormones being sent have changed and new messages are flying through the blood. The sugars, triglycerides, and amino acids released into the blood during digestion have change the status quo in the cells. The cellular machine switches gears and starts to move in a new direction. The body was in the fasting state and now it is in the fed state.
Metabolism is the process of snapping apart the macronutrients into their amino acid, fatty acid and sugar beads and then burning some of these beads to make energy and using others to build the new proteins, fats and carbohydrates. Carbohydrate metabolism, fat metabolism and protein metabolism are interwoven and what one does affects them all. We will go into detail on carbohydrate metabolism because that is the nutrient most directly involved in diabetes.
The first part of metabolism is catabolism when large molecules are torn apart into small ones and energy is produced. The second part of metabolism is anabolism when small molecules are used to build large molecules and energy is used. Active cells are going to have a higher metabolic rate than less active cells. Catabolism and anabolism are constantly occurring and in balance. Untreated disorders such as diabetes can disrupt this balance The body does not take in energy and ends up consuming itself.
The delicate balance and interplay of fat and carbohydrate metabolism is regulated by the hormones insulin and glucagon. In general, insulin tells the body that glucose is available – use it to make more of everything while you can. Glucagon tells the body that there is no glucose – find some way to get more into the blood and burn fatty acids for energy in the meantime.
This is the third of a five-part series on Metabolism.
When chyme exits the small intestine through the ileocecal valve and enters the large intestine, it is a fluid. By the time it leaves the large intestine through the anal sphincter it is a solid. Along the way water is absorbed from what is now called feces.
Fiber molecules are too large to be absorbed and humans do not have the enzymes to break them up, so both soluble fiber (dissolved in the chyme) and insoluble fiber exit the small intestine in much the same state as they entered. Another type of carbohydrate called ‘resistant starch’ also reaches the colon.
Human bodies may not have the enzymes to digest the soluble fiber but bacteria do. The bacteria that flourish in the properly seeded colonic garden take the “food” passing though the assembly line and ferment or eat it. If a favorite food is available, there can be a population explosion (much of the dry weight of feces is made up of bacteria) so bacterial bodies now join the assembly line procession. The by-products of bacterial fermentation are short chain fatty acids SCFA. Cells in the colon like to burn SCFA as fuel and they can also be absorbed into the blood where they have a beneficial effect on the body. Since the SCAF are absorbed they are a source of calories.
Finally the insoluble fiber, undigested food, unabsorbed nutrients, bacterial cells, and bile and other wastes leave your body as a bowel movement. This completes the absorption from your meal, it is now time for the second part –metabolism- to begin.
This is the second of a five-part series on Metabolism.
The purpose of your entire digestive system is to reverse the process of photosynthesis and liberate the energy locked within the glucose molecules But first it must digest or break down the plants components into small enough pieces to be absorbed.
Digestion begins in the mouth with a carbohydrate-digesting enzymes in your saliva. As you chew a piece of bread you will notice that it starts out savory but the longer you chew the sweeter it becomes. These are the sugar molecules being snapped off the larger starch molecule by enzymes–hence the sweet taste. Digestive enzymes snap larger molecules into two. Different digestive enzymes catalyze different types of macronutrients: proteases digests protein, lipases digests lipid or fat, and amylases digest carbohydrate. All of the digestive enzymes have names that end with “ase”.
As we saw in the last chapter, your digestive system is basically a long tube with muscular walls. From the perspective of your cells, it functions like an assembly line. They remain stationary while the meal moves slowly through the tube in front of them. Some of the cells work in another department, in the pancreas for example, and sends the products they make down a chute, the common bile duct for example which pours the product onto the assembly line as it moves by. Each type of cell does the same job over and over. The food is propelled along our assembly line by a series of wave-like muscle contractions called peristalsis. At each stop along the line the chewed meal is subjected to some process until it reaches the end and exits looking nothing like when it entered.