|
Insulin: The Good and the Bad
What's the first thing that comes to mind when you hear the word insulin?
Maybe it's diabetics, fat gain, or a number of other things. The truth is it's
these things and much more. In this article I will discuss what insulin
is and how it works, and why diets try to control it. I will also compare the
glycemic and insulin index to see how we can use these tools.
Lastly I'll explain insulin's effects on the brain and the dreaded low-carb
limp, plus list some points of interest.
What insulin is and how does it work
Insulin is a hormone produced by the beta cells of the pancreas in
response to raised blood glucose (sugar) levels. Its whole purpose is to
regulate the metabolism of glucose and other nutrients.
When your body goes without food for a time you develop a sensation of hunger,
which generally leads you to consume a carbohydrate (or any macro
nutrient) meal. These carbohydrates become converted to sugars in the
blood, which causes the release of insulin. The insulin
allows sugars to leave the blood and enter the cells of the body; this leads to
a change in brain chemistry and this change generates a feeling of satisfaction.
Over the course of hours, the insulin-to-blood sugar ratio will once more
change and brain chemistry will again cause a sensation of hunger.
For a more illustrated and in-depth look, let's say you eat an apple. Glucose (a
simple form of carbohydrate, converted form the complex carbohydrates
in the apple) will pass through your small intestines and into your blood (now
called blood glucose). Your body will sense this raise in blood glucose and will
signal your pancreas to release insulin, which allows and helps carbohydrates,
proteins and fats to enter cells.
This is necessary because cell membranes are made up of a fat matrix.
Along this fat matrix are small door-like portals called protein carrier
molecules. Through these "doors" insulin carries the nutrients
into cells in a process called facilitated diffusion. With this basic
knowledge we can now look at how diet affects blood glucose levels and learn how
to use insulin to our advantage.
Why try to control insulin through diet?
The pancreas secretes insulin, with the highest levels peaking
around 6 a.m. The pancreas also releases insulin 50 percent faster
in the morning. This means that even if you eat the same foods at different
times of the day, the amount of insulin you secrete varies. In
fact, a morning insulin shot reduces glucose 40 percent more than
an afternoon one. (Though I don't recommend it, this is something to keep in
mind for bodybuilders who choose to supplement with insulin).
The first question should be "why would we want to manipulate insulin?"
Permit me to explain. As shown above in the preceding paragraphs, insulin
is what "carries" nutrients into our cells. For example, imagine drinking a meal
replacement after working out and not having insulin. This would
cause high levels of blood glucose (hyperglycemia), as the nutrients
could not pass through the fatty matrix cell membrane without their "carrier."
Eventually the blood glucose would be excreted through the urine and wasted.
Therefore your cells would not receive fuel and wouldn't grow end of story and
end of life (hence the need of diabetics to inject insulin). Of
course the more nutrients that enter the cell the larger it will grow, be it a
muscle or fat cell.
If you read any of the diet books on the shelves of your local super market
you'll see that they all revolve around the principle of reducing insulin.
Why would someone want to do this? The theory is, by reducing insulin
through changes in diet, less insulin will be released and less
fat stored. Think of the portals on your cell membranes as an intersection, and
insulin as the stoplight. While insulin is present
it's a green light for nutrients to enter the cell and a red light for stored
energy to leave the cells. Therefore nutrients are either going in or going out.
This is why most find it very difficult to gain size and lose fat at the same
time, hence the need for bodybuilders to bulk up and then cut or
vice-versa.
Glycemic index
Most if not all of us have heard about the insulin index.
Countless books have been written about it and are some of the best sellers on
the market. The premise behind it is that certain foods cause blood sugar to
rise higher and faster than others. The thought is that if you avoid these high
glycemic foods, blood glucose levels won't rise as high, making you
releases less insulin, allowing you to store less fat. This
looks great on paper but what many of us don't know is how they obtain these
ratings. Here's how it's done. An amount of food containing 50 grams of
carbohydrate is given to a volunteer to eat. For example, to test boiled
spaghetti, the volunteer would be given 200 grams of spaghetti, which supplies
50 grams of carbohydrate. The volunteer's response to spaghetti (or
whatever food is being tested) is compared with his or her blood sugar response
to 50 grams of pure glucose.
Do any of you find this a little unusual? Who eats 50 grams of only one food at
a time? Most have tomato and meat sauce with their spaghetti, so now what is the
glycemic index of the meal?
It's also advised to avoid carrots because their glycemic index is so high. I
want to know who eats 50 grams of carbohydrates worth of carrots without
ranch dip, or anything else for that matter. Oddly enough a snickers candy bar
is allowed because it has a lower glycemic response. Interesting to think that
carrots are bad and snickers are good.
Graham crackers filled with partly hydrogenated soybean oil (trans fats) and
sugar are better for you than whole grain oat cheerios; milk chocolate loaded
with saturated fat and sugar is better for you than nonfat yogurt and
coca cola is better for you than Gatorade. Like I said, great on paper but
ridiculous when applied literally to your diet.
In case you cared
Though I'm not a big fan of the glycemic index, it's not totally useless. For
that reason I'll list the blood glucose responses of commonly eaten foods that
are thought to be healthy but are wolves in sheep's clothing.
Food Plasma Glucose, mg/100ml
Cheerios At 45 minutes after ingestion, over 100
Quaker Instant Oatmeal Peaches and Cream At 30 minutes after ingestion, nearly
120
These two foods are listed to show you how a food that looks good for you may
actually be harmful. Cheerios is touted as toasted whole grain oat cereal,
�part of a heart healthy diet, and we are told that the soluble fiber
in cheerios can reduce your cholesterol!
Heres what they dont tell you. The first problem is that the major ingredient
of cheerios is modified cornstarch! Of course they hid this in the ingredients
under whole grain oats (hardly). Secondly, of the 22 grams of carbs, 3 are
dietary fiber. Of those 3 only 1 gram is soluble fiber. One measly gram! It
takes at least 3 grams (according to the small fine print on the cheerios box)
to help with heart disease. You might as well just eat a sheet of paper and get
more fiber.
Bagel At 30 minutes after ingestion, 115
Bagel w/peanut butter At 45 minutes after ingestion, 100
Here we see how bad a bagel can be. It looks like if we add peanut butter we
lower blood glucose levels by 15mg/100ml and delay its time to peak for 15
minutes. The only problem is its effects on insulin levels. As will be explained
below, adding fat with carbohydrates increases insulin secretion even though
plasma glucose response is reduced!
Insulin index
The insulin index score is a ratio based on insulin
levels found over 2 hours after consuming 1000 calories of the
test food to 1000 calories of white bread. Now we are talking
calories to calories (though that much bread is an unrealistic
representation of a meal). On some foods tested, the glycemic index was higher
than the insulin score, while on others the insulin
score was higher than the glycemic index. For example: pasta, rice, and potatoes
have glycemic indexes far greater than insulin scores, yet beef
and fish have insulin scores far higher than their glycemic index.
What does this tell us? It tells us that our blood sugar level isn't the only
thing that determines the amount of insulin released.
Protein rich foods produce a low blood glucose response but it
does not follow that there is a correspondingly low insulin
response. The glycemic index does not consider concurrent insulin responses,
only blood sugar responses. For example, protein rich foods or the addition of
protein to a carbohydrate rich meal can stimulate a modest rise in
insulin secretion without increasing blood glucose concentrations. Adding fat to
a carbohydrate rich meal also increases insulin secretion even though plasma
glucose response is reduced. So protein and fat rich foods also induce
substantial insulin secretion despite producing relatively small blood glucose
responses.
Insulin on the brain
When you go into ketosis your body reacts as if it's starving and switches over
to releasing fat stores for fuel. This sense of starvation acutely suppresses
reproductive function by inhibiting the release of gonadotrophins. This occurs
because of reduced neuron signaling by insulin in the brain. (Note: it was
thought that the brain was insulin insensitive because its ability to use
glucose does not require insulin. Research however demonstrates that insulin is
transported across the blood brain barrier and that insulin receptors are
concentrated in brain areas involved in energy and hormonal homeostasis. More on
this later.)
The low carb limp'
So now we see why low insulin diets are very popular these days. Just look what
diet book is the highest seller and you will see that it's the Atkins Diet.
All of us know at least one person that is on or was on the low-carb road, and
we probably saw a tremendous loss of body fat occur. These diets, like most, are
usually accompanied by thermogenics of some type mostly ephedrine and caffeine.
An interesting phenomenon that some will experience on a low-carb diet in
conjunction with thermogenics is what we call the low-carb limp. Those that
have experienced this know exactly what it means. It seems that the more
sexually attractive you become by dieting low-carb, the less you can sexually
function. Throw in a thermogenic stack and erections are almost non-existent.
It appears that an increase of calories in one's diet does raise anabolic
hormones such as insulin-like growth factor one (IGF-1) and testosterone. Now
while on a low-carb diet many will notice a loss of appetite. This means a
decrease in calories. Could this possibly bring with it a decrease in
testosterone? Well, higher levels of testosterone are found with greater
carbohydrate intake than with protein. In fact, replacing carbohydrates with
protein has shown to decrease testosterone levels!
Now what happens when you cut your carbohydrates? You increase your protein.
This decrease in carbohydrates coupled with a lower appetite and higher protein
intake equals less calories and lower amounts of insulin-stimulating foods.
Thus, less insulin crosses the blood-brain barrier, and less insulin in the
brain signals the body that it's starving. This turns off the release of
gonadotrophins.
You are now producing less testosterone; this in and of itself can affect
erections (though it has been shown that some hypogonadal men can achieve
erections just as easily as normal functioning men can). On top of producing
less testosterone, add a thermogenic stack. Not only does this further reduce
testosterone levels but also the ephedrine stimulates alpha-receptors. When this
happens your body goes into a fight or flight response and all non-necessary
functions for immediate survival shut down. In regards to insulin, ephedrine and
caffeine decrease insulin sensitivity. This causes reduced brain insulin
signaling and further inhibition of gonadotrophins. So, long-term use of
low-carb diets can significantly reduce testosterone levels, which can in turn
lower training tolerance and sex drive.
Points to remember
Insulin is good, not bad. It's not something you want to suppress, just control.
Though it can increase fat storage, if you work out and manage your diet
correctly you can store the majority of your calories in muscle tissue.
The glycemic index is not realistic in regards to how we eat. Though the insulin
index is not perfect either, it's much better and tells us what we really need
to know.
Insulin does cross the blood-brain barrier and affects energy and hormonal
balance in a positive way.
Low carbohydrate diets are effective, but have the ability to reduce the release
of gonadotrophins (i.e., testosterone).
Ephedrine and caffeine are also effective, but have the ability to reduce
testosterone and increase insulin resistance.
What to do about it
The role of diet
Fats:
Research has shown a strong connection between the intake of essential fatty
acids (GLA and DHA) and reduced insulin resistance. Both human and animal
studies show that a dietary intake of EFAs increases the unsaturated fatty acids
in membrane phospholipids and makes the individual more insulin sensitive.
Prostaglandin E1 makes insulin work more effectively. GLA increases this
beneficial prostaglandin. The richest known source of GLA is borage oil (23% GLA).
Gamma-linolenic acid (GLA) is also found in hemp oil and evening primrose oil.
A high fat diet is not necessarily bad, provided it contains a sufficient
proportion of EFAs. Similarly a low fat diet is not necessarily good if it does
not provide the body with a sufficient amount of essential fatty acids. A
fat-restricted diet will actually lead to an unwanted stimulation of lipid per
oxidation and formation of pro-inflammatory substances, involved in the
development of chronic degenerative diseases such as arteriosclerosis and
rheumatoid arthritis.
Not only do we need a sufficient amount of EFAs, we also need the right EFAs in
a balanced proportion (two parts of omega-6 to one part of omega-3). In short,
we need to reduce the intake of omega-6 oils, except GLA, and increase omega-3
fatty acids, particularly DHA (DHA is plentiful in cold water fish, such as
salmon, mackerel, herring and tuna that feed on DHA-rich micro-algae).
Protein:
When amino acids are administered simultaneously with carbohydrate, they
strongly potentate the glucose stimulus for insulin secretion. Thus, athletes
should consider ingesting both nutrients within a given meal, particularly
following a bout of exercise. This may serve to enhance glycogen re-synthesis
and favorably impact protein turnover.
The importance of Exercise
Resistance training:
Enhances muscle glucose uptake.
Enhances insulin sensitivity; this may persist 12-24 hours post-exercise but
begins to decline in as little as 1 to 2 days without exercise.
It has been shown by a number of papers that resistance training for insulin
resistance is better than aerobic training. There are a variety of other reasons
too. Resistance training is referring to muscular exercises. If you just do a
biceps curl, you immediately increase the insulin sensitivity of your biceps.
Just by exercising you are increasing the blood flow to that muscle. That is one
of the factors that determine insulin sensitivity. It has been shown
conclusively that resistance training will increase insulin sensitivity.
It has been found that several months of resistance training leads to a much
greater increase in insulin sensitivity than seen in patients who engage in
aerobic training. This is attributed to an increase in glycogen storage.
It has been shown that bodybuilders, who traditionally employ a high volume
style of training, favorably alter glucose tolerance and insulin sensitivity.
A quick warning: Beware of excessive eccentric training:
Muscle damage impairs insulin stimulation of IRS-1, PI3-kinase, and Akt-kinase
in human skeletal muscle. Del Aguila, Luis F., Raj K. Krishnan, Jan S. Ulbrecht,
Peter A. Farrell, Pamela H. Correll, Charles H. Lang, Juleen R. Zierath, and
John P. Kirwan.
To quote their findings:
In summary, the physiological stress associated with muscle damage impairs
insulin stimulation of IRS-1, PI3-kinase and Akt-kinase, presumably leading to
decreased insulin-mediated glucose uptake. Although more research is needed on
the potential role for TNF-alpha inhibition of insulin action, elevated TNF-alpha
production after muscle damage may impair insulin signal transduction.
Quasi-legal drugs
Metformin
Though controversial, it has been proven in studies that as people gain weight,
they develop more fat cells.
Metformin works by increasing the number of muscle (and possibly
adipocyte [fat cell]) insulin receptors and the attraction for the
receptor. It does not increase insulin secretion, it only increases
insulin sensitivity. Therefore, Metformin is not associated with causing
hypoglycemia. This activity reduces insulin levels by
increasing the sensitivity of peripheral tissues to the effects of insulin by
restoring glucose and insulin to younger physiological levels that
may cause weight loss and most certainly a decrease in the body�s total fat
content.
Metformin has been shown to cause a reduction in total cholesterol, appetite,
weight, and the body�s total fat content.
Parlodel (Bromocriptine)
Stimulator of dopamine receptors, inhibitor of prolactin secretion.
Inhibits the secretion of the anterior pituitary hormone prolactin without
affecting normal levels of other pituitary hormones.
Has a beneficial effect on clinical symptoms and on glucose tolerance.
Restores a normal pattern of LH secretion.
Reduces the size and number of nodules of the breasts and alleviates the breast
pain often associated with such conditions by normalizing the underlying
progesterone/estrogen imbalance.
At the same time it reduces prolactin secretion in patients with elevated
levels.
Indications: hyperprolactinaemia in men- prolactin- related hypoganadism.
Antidepressant properties.
After reading that list tell me if bromo is not one of the greatest unknown
drugs out there. For almost all of the problems steroids cause, Bromocriptine
can help solve them. For example, it inhibits prolactin secretion which could
solve the problems of gyno caused by deca and/or tren (though its still
debatable if either cause prolactin secretion), does not effect other pituitary
hormones, has a beneficial effect on glucose tolerance (some steroids cause
insulin resistance), restores normal LH secretion (ala clomid, nolvadex, HCG),
reduces size and number of breast nodules (anti-gyno properties [even in already
developed nodules]) and alleviates breast pain associated with
progesterone/estrogen imbalances (no more itchy, prickly nipples), treats
hyperprolactinaemia, hypogonadism and has antidepressant properties (in some
users, steroids cause depression).
Clearly this is a supplement all who are on should be using.
One last trick up the sleeve
Patients used a hot tub for 30 minutes a day, six days a week, for three weeks.
During the three-week period, the patients weight decreased by a mean of
1.7-2.7 kg. Their mean fasting plasma glucose level decreased form 182 mg per
deciliter to 159 mg per deciliter, and their mean glycosylated hemoglobin levels
decreased form 11.3 percent to 10.3 percent. They also reported improved sleep
and an increased general sense of well-being. Most likely the benefits resulted
from increased blood flow to skeletal muscles.
by Glen Neilson
Books and Courses
|
Great Websites
|
Excellent Stores
|
Recipe Cook Books
|
|
|
