Insulin Index - Control Your Sensitivity
Author: Technical Panel
SENSITIVITY AND TESTING
Individual Differences - Are You Sensitive?
In the last section it was recommended splitting six daily meals up into about three protein and carb meals and about three protein and fat meals. This plan works well for most people in terms of maximizing muscle gain while minimizing fat gain when overfeeding. However, just like different training programs are necessary for different individuals, individual responses to nutrition are varied. So rather than telling you that there's one program for all, we hope to give you some tips so that you can determine which eating plan is best for you.
The factors governing your response to different nutritional intakes are pretty diverse, but one major factor that has been focusing on lately is insulin and glucose tolerance. Insulin sensitivity seems to be the most important factor dictating how the body will handle carbs. For those who have high insulin sensitivity, the body responds to carb intake with small insulin surges. Although the insulin surges are small, the cells are very responsive to that little amount of insulin and do a great job of becoming anabolic. Since lots of insulin can inhibit fat loss, the ideal scenario is to become very insulin sensitive so that only small amounts of insulin are required for anabolism and so that those small amounts of insulin don't prevent fat loss.
In most experience, individuals who have high insulin sensitivity maximize their muscle to fat ratio on diets that are high in carbs and lower in fat (50% carbs, 35% protein, 15% fat). Those with moderate insulin sensitivity tend to do best on diets that are more isocaloric (30% carbs, 40% protein, 30% fat). And those with poor insulin sensitivity do best on diets that are low in carbs (50% protein, 35% fat, 15% carbs). This again, correlates well with natural genetic make-up of metabolic typing.
So within the framework of this study on insulin, if you're highly insulin sensitive, more than three of your daily meals would be carb plus protein meals. If your insulin sensitivity isn't so great, more than three of your meals will be protein plus fat.
Insulin Sensitivity - Testing
So the next question is how do you know if you're sensitive or not? The easiest thing to do is just think about what types of diets you respond to best. If low carb diets work great for you, then you're probably insulin insensitive. If you can eat a lot of carbs and not get fat then you're probably insulin sensitive. If you'd like something more concrete than that, read on. It may also be a good idea to complete the questionaire on the metabolic typing page.
Preferred methods that, although more time consuming, are objective would be things such as an oral glucose tolerance test. For this you need to go to your local pharmacy and purchase a glucometer, some glucose test strips, and a standard glucose beverage (ask your pharmacist about this because it has to be a specific kind. Pepsi won't work). A glucometer is a small device that takes pin pricks of blood from the ends of your finger and analyses the level of sugar in the blood. Once you've got the goods, you'll plan your test.
After going at least 24 hours without exercise (do this test after a day off from training), as of course exercise alters blood sugar levels, you'll wake up in the morning (fasted at least 12 hours) and you'll take a blood sample from your finger tip. Write down this number. Then drink your glucose beverage and continue to take blood samples at 15, 30, 60, 90, and 120 minutes. Record all the numbers at each time point. Here's a little chart of what you should expect:
Normal Insulin Sensitivity and Glucose Tolerance
Excellent Insulin Sensitivity and Glucose Tolerance
Fasted Blood Glucose
Peak Blood Glucose
<180mg/dl at peak
Time to Maximum Blood Glucose Level
Time Back to Fasted Glucose Level
The second test that we like to recommend for assessing insulin sensitivity is a fasted glucose and insulin test. For this you need to see your doctor. This test is simply a blood draw in the fasted state. It's easy to do. Just schedule an appointment, the nurse will do a single blood draw, and then the lab will measure the levels of insulin and glucose in your blood at this time. Using one of the following equations, you'll have both an insulin sensitivity score and a pancreatic responsiveness score:
Insulin Sensitivity =
Fasted Insulin (mU/L) / 22.5 x E to the X e-ln(Fasted Glucose (mmol/L))
Fasted Insulin (pmol/L) x (Fasted Glucose (mmol/L) / 135)
Pancreatic Beta Cell Function =
(20 x Fasted Insulin (mU/L)) / (Fasted Glucose (mmol/L)-3.5)
(3.33 x Fasted Insulin (pmol/L) / (Fasted Glucose (mmol/L)-3.5)
If you're not a math whiz or don't own a calculator, have your doctor do the math for you. Remember, you have to go to his office to get the test done in the first place. Once you have these values, compare your numbers to the following to see how sensitive you are:
Lower score = more sensitive
Normal insulin sensitivity: score should be below 2
Excellent insulin sensitivity: score will be around 0.5
Pancreatic Beta Cell Function
Higher = better pancreatic function and insulin release
Normal pancreatic function: score should be about 100
Excellent pancreatic function: score will be above 200
Once you've collected these measures, you'll have a better indication of what type of diet you need to consume. Its recommended doing these tests at least once every few months to see how your diet and training is impacting your insulin sensitivity. Insulin sensitivity can change dramatically very quickly, based upon the quality of your diet. Abusing your pancreas over a short period of time is a sure fire way to contribute to insulin insensitivity. If you catch it in time, you can regain some sensitivity. Over abuse and your likely to have diabetes for good - and its unlikely you will have built a superior physique in the process. Much rather the opposite. You can read more below about how to increase your insulin sensitivity, if you have had the misfortune of abusing it for too long, say with an extended high carb, high calorie, bulking up diet.
How To Increase Insulin Sensitivity
So let's assume that you've done the tests mentioned above and you weren't happy with the results. Or you have an underpinning idea or gut feeling that you may indeed be insulin resistant or insensitive. Well, instead of resigning yourself to a flabby midsection for the remainder of your days there are some things you can do to increase insulin sensitivity. Below is an outline of beneficial things that can promote better insulin sensitivity. Of course eating in a manner as outlined above, and in the metabolic typing section will also improve your insulin responses to food.
Both aerobic and resistance training greatly increase insulin sensitivity through a variety of mechanisms. So include both in your program. It has been seen to have tremendous increases in insulin sensitivity with three to four intense weight training sessions per week lasting 1 to 1.5 hours per session. These sessions should be coupled with at least three or four aerobic sessions lasting 30 minutes per session. To really target insulin sensitivity, you'd want to perform weight training and cardio separately. Remember these are tips to improve insulin sensitivity - they are not targeted perhaps for your own unique individualised goals.
In addition, supplements like omega 3 fatty acids, fish oils, alpha-lipoic acid, and chromium can increase insulin sensitivity. Its typically recommended starting out with 600 mg of alpha-lipoic acid (ALA) and concentrated fish oils containing a total of six to ten grams of DHA and EPA (the most active omega 3 fats in fish oils). Remember how important fish oils are. Have a read of the section on fats to understand more. Needless to say, when you are eating to maintain and improve your insulin response, you should be consuming a number of meals that are protein and fat based only. And the fats should come first choice from fish oils where possible.
On the flip side, stimulants like ephedrine and caffeine can decrease insulin sensitivity due to their effects on metabolism. Furthermore, the low carb, high-fat diets that have become popular can also lead to decreased insulin sensitivity when followed for long periods of time. This can pose potential problems or insulin insensitivity when low to no carb dieting for extended periods for fat loss while simultaneously taking caffeine and ephedrine based stimulant fat loss aids. It is better to cycle these stints into a periodized eating approach or not remain on them for too long a time period.
So if your insulin sensitivity isn't ideal the first time you measure it, try the approaches listed above. Then go back after a month or two and re-test. You'll see that the numbers look much better