Monday, February 11, 2008
By Andrew McInroy.
Welcome back! In this article, the greatest secret and most useful aspect of nutrition will be revealed! I guarantee that it is something that you will be thankful you learned. Furthermore, you will also learn about the importance of water. Let's jump right into the action with carbohydrate digestion!
You chew the food or shake (yes, "chew" your shake - the saliva process is critical) and salivary amylase (a digestive enzyme) works on it in the mouth.
You swallow it and it travels down the esophagus. Your stomach churns it up. (Little to no digestion here) Your small intestine receives the carbohydrates and this is where the majority of the digestion takes place; the pancreatic amylase (released from the pancreas into the small intestine) acts on breaking the carbohydrates into the simple sugars (If they are not already in the form of simple sugars).
Once in the form of simple sugars, these simple sugars are absorbed from the intestine, passed the intestinal absorptive wall, into capillaries which then send the simple sugars to the hepatic portal vein. The hepatic portal vein is basically the nutrient highway to the liver.
The hepatic portal vein carries simple sugars to the liver. IMPORTANT - in the liver, the simple sugars that are not glucose (fructose and galactose), are transformed into glucose. Glucose can be stored in the liver as glycogen (long chains of glucose stored in cells as one big energy reserve). Glucose leaves the liver and enters the blood stream. IMPORTANT: THE ONLY SIMPLE SUGAR THAT ENTERS THE BLOOD STREAM IS GLUCOSE (Hence, blood glucose!). Once glucose is in the blood, this is detected as an increase in blood glucose and therefore, your body reacts by signaling the pancreas to release INSULIN (Considered to be of the most anabolic hormones).
Insulin acts on muscle and fat cell receptors to basically "open up the gates" and allow glucose to flow inside. Most carbohydrates go to muscle cells. Once inside the muscle cell, glucose becomes glycogen - i.e stored energy and power for your muscle (mentioned above). IMPORTANT: Insulin will be discussed with high regard throughout this piece (eventually in higher detail) and it is, in my opinion and many others, the most important factor in maintaining a good diet. KEEP THIS IN MIND AT ALL TIMES.
Interestingly enough, another hormone called glucagon, acts on cells and makes them breakdown the glycogen and release it back into the blood stream as glucose.
Insulin is a hormone that is produced in the pancreas and is secreted in response to increased blood glucose levels. The body likes to be in internal balance and this internal balance is called homeostasis. When blood glucose levels get too high, they are not in homeostasis and this is why insulin is secreted. Too much glucose in your blood can be dangerous.
THE GOAL IS TO CONSUME CARBOHYDRATES THAT WILL BE SLOWLY DIGESTED AND CAN BE DEALT WITH EASILY BY THE BODY, WHILE PROMOTING GOOD INSULIN SENSITIVITY.
What is insulin sensitivity? Insulin sensitivity relates to how sensitive the receptors are on your cells to insulin. If the receptors are sensitive (which is a good thing), the insulin attaches and has no problem with moving glucose from the blood into the cell. However, if you are insulin resistant (something you must avoid), the receptor cells are not responding to the insulin and therefore, will not let as much glucose in. Obviously this is scary because we want to keep blood glucose levels normal and if we can't do that, then we may face problems like hyperglycemia.
EXTREMELY IMPORTANT: THE CONCEPT OF COMPLEX CARBOHYDRATES AND SIMPLE SUGARS AND THEIR EFFECT ON BLOOD GLUCOSE LEVELS, INSULIN SENSITIVITY, AND FAT LOSS.
In the small intestine, carbohydrates are broken down by pancreatic amylase into simple sugars. They must be simple sugars before they can be absorbed by the intestinal absorptive wall.
Remember the above statement; I cannot stress how important it is. Now, let's look at complex carbohydrates vs. simple sugars and their digestion.
If a complex carbohydrate enters the small intestine, it is a much larger molecule and therefore requires more time to digest. Remember that all complex carbohydrates are just like big chains of simple sugars. So, as pancreatic amylase acts on complex carbohydrates, there is a slow release of simple sugars from the larger carbohydrate molecule and these simple sugars are then absorbed into the intestinal absorptive wall. This allows for a nice steady release of glucose into the blood system (after it passes through the capillaries, hepatic portal vein, and liver).
With a nice release of glucose into the blood stream, insulin can be released at a nice steady rate and therefore it can deal with the glucose at a calm and steady rate and is usually able to get the majority of glucose into muscle cells, as opposed to fat cells (this of course depends on current glycogen stores in the muscle cells). But it is a general rule that you consume complex carbohydrates in order to regulate the release of glucose into the blood stream and therefore allow your insulin to deal with lowering blood glucose levels in a calm and orderly fashion.
Ultimately, this will lead to good insulin sensitivity and will help prevent fat gain and promote fat loss. Why? Check out what happens when simple carbohydrates are consumed:
So as opposed to the large molecule that needs to be worked on for a while to be digested and will digest gradually and calmly into the blood stream, the simple sugars are much faster.
Why? THEY ARE ALEADY IN THE SIMPLE SUGAR FORM AND REQUIRE LITTLE OR NO DIGESTION IN ORDER FOR THEM TO BE ABSORBED INTO THE INTESTINAL ABSORPTIVE WALL AND THEREFORE ENTER THE BLOODSTREAM FAST. THIS CAUSES AN INSULIN SPIKE.
An insulin spike is when blood glucose levels are increased rapidly and the homeostasis is thrown out of balance greatly and this causes a strong response from the pancreas and it releases a lot of insulin to deal with the dangerously high glucose, hence, an insulin spike.
Basically, the insulin goes nuts on getting the dangerously high blood glucose back to normal and tries to shove it into any nearby cells. So here we have the muscle cells and the insulin is beating down on their insulin receptors and the muscle cells can only accept so much glucose. But, because there is such a large amount of insulin, due to the insulin spike, the insulin keeps beating on the insulin receptors, regardless of whether or not the cell can take more glucose.
To get the blood glucose levels down, insulin works on insulin receptors of fat cells and therefore, glucose enters the fat cells too; here are some of the reasons:
1) Mainly because the blood glucose is high and it has to eliminate this threat fast and it cannot store all the glucose in muscle cells fast enough so glucose will go to fat cells too.
2) Muscle cells fill up with the glucose and therefore the glucose has to go somewhere else: fat cells.
3) Also, the muscle cells may be insulin resistant and the fat cells are still insulin sensitive: this leads to fat cells taking in glucose.
So the problem with simple carbohydrate consumption is two factors:
1) Insulin resistance from the insulin constantly beating down on the insulin receptors of muscle cells
2) Fat storage due to the said reasons.
The conclusive message: You will want to consume complex carbohydrates for almost all meals with the exception of post workout meals, as you will see. This is to promote healthy insulin sensitivity and to prevent dangerous blood glucose levels, prevent insulin resistance, and prevent fat storage.
NUTRITIONAL VALUE OF CARBOHYDRATES = 4 calories per 1 g of carbohydrate
Example: Dave eats 1 cup of oats which contains 60 g of carbohydrates. Therefore:
60 g of carbohydrates x 4 calories = 240 calories from carbohydrates
Fats, scientifically known as lipids, are a component in the body that are often said to be bad and told to be left out of the diet. If someone says this to you, they're an idiot. That is not to say that you should eat a ton of fats, as some fats are definitely bad for you, but there are also good fats that are essential (Essential Fatty Acids [EFA], we will learn more about this later on). Fats, when digested are broken down into fatty acids. Fatty acids play many key roles in our biology.
Fats serve many purposes such as:
-Some vitamins are fat soluble
-They provide a lot of dense energy
-They make you feel fuller
-Are a major component of cell membranes
There are three types of lipids in the body:
1) Triglycerides - 95% of lipids within foods and humans are triglycerides.
2) Phospholipids - These are a major component of cell membranes.
3) Sterols - Yes, cholesterol is a fat/lipid.
Triglycerides are the main type of fat found in humans and food. Adipocytes, or fat cells, are filled with triglycerides; the more triglycerides you have, the fatter your fat cell. It is also important to note here: 18-24 months after birth, our body stops making fat cells. Thus, fat cells only can get bigger as they gain more and more triglycerides (or smaller as they lose more and more triglycerides).
Triglycerides are basically structured like this:
-1 glycerol molecule
-3 fatty acids
(Hence tri(3 fatty acids) and glyceride(glycerol))
Fatty acids are composed of chains that are 8 - 22 carbons in length. At one end of the fatty acid there is a methyl group (CH3) and at the other end there is an acid group (COOH). The rest of the carbons form bonds with hydrogen and bonds with each other.
WHETHER A FATTY ACID IS SATURATED, MONOUNSATURATED, OR POLYUNSATURATED DEPENDS ON HOW MANY BONDS CARBON MAKES AVAILABLE FOR HYDROGEN ATOMS TO BOND TO (EXCLUDING THE METHYL AND ACID GROUPS).
NOTE: If you don't know your chemistry, read this anyway, you can still grasp the concept.
Saturated Fatty Acids are fatty acids where the carbon atoms have made all their bonds (aside from the methyl and acid groups) available for hydrogen bonds, hence, it is completely saturated with hydrogen atoms where possible. Basically, the maximum amount of hydrogen is being attached to the fatty acid.
Saturated fats (fats that contain saturated fatty acids) are solid at room temperature and can be found in foods such as animal meat. Ex: fat on a steak.
SATURATED FATS are important in the production of testosterone.
Monounsaturated Fatty Acids are fatty acids where ONE double bond is formed between two carbons (called the point of unsaturation) and since the bond is being used between two carbon atoms, this makes it so the maximum amount of hydrogen cannot attach to the fatty acid. (C=C)
Polyunsaturated Fatty Acids are fatty acids where double bonds are formed between TWO OR MORE carbon pairs. This makes the fatty acid even less saturated than the monounsaturated fatty acid. Therefore, the amount of hydrogen atoms able to attach to the fatty acid is further reduced. (C=C-C=C)
Unsaturated fats (fats with unsaturated fatty acids) are liquid at room temperature and are often called oils. Example: Fish oils and vegetable oils.
ESSENTIAL FATTY ACIDS are fatty acids which we must get from our diet or cannot make in sufficient quantities (similar to essential amino acids). EFA help with the body's immune system, help regulate blood pressure, reduce infection, manage blood lipids, and helps with the creation of blood clots.
Two essential fatty acids are:
Linoleic acid (omega-6 fatty acid) (polyunsaturated fatty acid)
Linolenic acid (omega-3 fatty acid) (polyunsaturated fatty acid)
Note: "omega-x" just describes the chemical structure of the fatty acid but is negligible in importance for this article.
Sources of essential fatty acids:
-fish and fish oil
-I do not recommend using flax seed oil because a conversion must take place to achieve the essential fatty acids. However, fish oil already has its essential fatty acids and does not require conversion.
TRANS-FATTY ACIDS are fatty acids that are chemically produced and rarely found in nature. What is the difference between these and other fatty acids? They are usually chemically produced in a process called hydrogenation where carbon bonds are freed up and hydrogen atoms join. This causes the fatty acid to become saturated. So is this just a saturated fat? NO! Saturated fats have a 'cis' structure (bent structure) while the trans-fats have a 'trans' structure (straight structure). So is straightening out the fatty acid a big deal?
Trans-fatty acids are something you always want to look out for on nutrition labels and are often used in deep frying. You will definitely want to avoid trans-fatty acids as they have been shown to have many negative effects such as increase bad cholesterol and decrease good cholesterol and furthermore it may cause coronary heart disease.
Examples of sources of trans-fats:
-Pretty much anything that is deep fried
Phospholipids help in the formation of cell membranes and are materials for special functions such as the eye and nerve sheath. The phospholipids will not be focused on for this article.
Cholesterol is a sterol and it helps in the production of steroid hormones (like testosterone!), and also is used in the synthesis of bile and vitamin D.
Examples of sources of sterols, mainly cholesterol:
Fat Digestion will not be addressed in this article; Carbohydrate digestion is of the most significance.
NUTRITIONAL VALUE OF FAT = 9 calories per 1 g of fat
Example: Dave consumes a whole egg that contains 5.3 g of fat. Therefore:
5.3 g of fat x 9 calories = 47.7 calories
Water is so important and yet so many people avoid it. Why? Probably because they don't like having to use the bathroom all the time, but believe the athletic community: it is highly anabolic. Water has many benefits and this article will not address each and everyone but some important ones as they pertain to athletic performance.
clears out toxins
Makes supplements like creatine more effective because creatine pulls water into muscle cells and, for this, you'll need ample water.
Many vitamins are water soluble so you need water to make the vitamins function properly.
for every gram of glycogen stored in cells, 3-4 grams of water will be stored. This can cause some serious cell volumization.
helps to regulate body temperature.
Recommended Water Intake:
Daily: 4-8 L (1-2 Gallons)
Game: 1-2 L
WATER NUTRITIONAL VALUE = Does not contribute calories.
Conclusion to Part II: Carbohydrate digestion and metabolism is extremely important in achieving your goals. Now that you know the science behind the macronutrients, you are now ready to build your diet - but that will have to wait until next time! Until then, make sure to stay determined, dedicated, and disciplined and say no to that chocolate bar, ice cream, etc. because you now you know what will happen! In Part III we will be revealing the secrets of how to build the perfect diet to promote strength, explosiveness, mass increments, power and more. Have a great day and thank you for your time