Why do I need to know about insulin?
Insulin has a direct effect on both fat storage and the release of fat as energy. For some it can be a cause of energy levels crashing after eating. This can lead to drowsiness and hunger and sugar cravings that can cause you to snack and put on weight. It also effects different people to a different extent. Once you know how and why insulin works, you can both lessen its impact and manipulate it to your advantage. On the other hand, left unchecked, if your body gets to the point it can no longer regulate insulin properly you will become diabetic. Without medical intervention the condition will become fatal. In the large majority of cases, diabetes (type 2 diabetes that is - not type 1) is fully preventable simply by not being overweight and not carrying too much visceral fat.
What is insulin?
Insulin is an important hormone and protein secreted into the blood by the pancreas to regulate blood sugar (glucose). Too much blood sugar is fatal to the body. It is directly linked to carbohydrates intake (and to a lesser extent protein), as carbohydrates are the main source of providing blood sugar. There should always be a low fluctuating amount of insulin in your blood to regulate normal levels of blood sugar. A normal fasting (no food for eight hours) blood sugar level is between 70 and 99 mg/dl. A normal blood sugar level two hours after eating should be less than 140 mg/dl. Blood sugar levels continuously higher in these circumstances indicate increasing insulin resistance and health problems developing.
What does insulin do?
Insulin is a powerful anabolic protein. It preserves body cells both preventing muscle tissue break down, and restricting fat being used as an energy source. And in doing so, performs its primary role of keeping blood sugar levels inside a normal range very logically and efficiently.
When blood sugar levels rise, after eating carbohydrates for instance, insulin is secreted from the pancreas to signal to cells that they need to open their gates to store all the extra blood sugar. First stop, the muscles and liver to store the excess blood sugar as glycogen. Second stop, after the muscles and liver are full, storing it in adipose tissue as body fat. The more sugar you consume in your diet (carbohydrates), the more insulin is needed to be produced.
Insulin is like a switch that docks onto the surface of the body cells, preserving them, and telling them to open their gates to blood sugar and protein. By restricting the release of energy from fat and muscle stores, insulin allows the excess sugar in the blood to be used temporarily as the bodies main fuel source, whilst also storing it as quickly as possible as potential energy, in the form of glycogen in the muscles and liver, or body fat in adipose tissue. This returns the blood sugar levels back to safe levels as quickly as possible.
So insulin is what allows the vital process of sugar to be used as immediate energy, and stored as potential energy in two ways. Firstly as glycogen in the muscles and liver, and then as body fat. And in doing so, insulin detoxes your blood, prevents muscle loss, and preserves your energy stores at the same time. That's good right? So why all the bad press?
The main issue with insulin is insulin sensitivity. Insulin sensitivity is genetically different for everyone.
If you have a high insulin sensitivity (low insulin resistance), this is good. Your cells respond quickly, with no resistance, to the insulin 'switch' and happily open up to store blood sugar as glycogen, and more of it. The excess blood sugar and insulin are all cleared from your system quickly as insulin's job is done fast. Less insulin is also required to get the job done. This also means that less fat is stored and less fat is restricted from being released as energy.
If you have a low insulin sensitivity (high insulin resistance), this is not good, and can be very dangerous. Your cells respond poorly to the insulin 'switch' and require a lot more insulin in the blood to open up to store blood sugar as glycogen. And they store less of it, leaving more of the excess blood sugar to be stored as fat. As a result of a person's resistance to insulin, the higher levels of blood sugar and insulin take a much longer time to clear from their system. This has the adverse effect of their blood sugar and insulin levels staying high with insulin continuing to restrict the release of fat as energy and store more energy as body fat.
Although you can dramatically improve your insulin sensitivity with exercise, insulin sensitivity can vary greatly genetically from person to person. However, relative to your own insulin sensitivity, your body is always most sensitive (this is good) to insulin first thing in the morning and with in the 60 minutes after exercise. This is because your glycogen levels will have been depleted either from the 5 to 8 hours overnight fast whilst asleep, or from the exercise. The higher your exercise intensity, the greater your insulin sensitivity will be post workout as your body will have a greater need to refill those glycogen stores and stop them depleting any further. HIIT routines have been proven to massively improve insulin sensitivity. Not only do they help to rapidly burn away the visceral body fat that actively increases your resistance to insulin, they make your muscles stronger and more efficient, and are powered mainly from burning glycogen, adapting them to take in and store more glycogen, and at a faster rate as you become fitter. This is what you want, for your body to prefer to store excess sugar as future energy stores in the muscles and liver, rather than as body fat. And it's exercise, in partcular HIIT and intensive resistance based training, that will achieve this for you the best.
An insulin spike is a sudden rush of insulin produced into the blood to deal with a large amount of sugar entering the blood. On a graph showing blood insulin levels over time, it would appear as a sudden spike, with the magnitude of the spike dependant on your insulin sensitivity and the amount of sugar that entered the blood at that time. Depending on your insulin sensitivity, an insulin spike will clear out the majority of the glucose in the blood, directing it into muscle and fat cells. Insulin spikes can often cause your blood sugar to drop too low after the blood sugar is dealt with by the insulin, causing that drowsy sensation that makes you feel hungry and crave more sugar.
Small doses of insulin dealing with small doses of blood sugar (ie from slow release low glycemic foods and low glycemic loads) will get used as energy or stored in the muscles and liver as glycogen. An insulin spike, a large dose of insulin dealing with a large dose of blood sugar at once (ie from high glycemic loads), will use what it can for energy and restoring glycogen levels, and store the surplus as fat for later. Your insulin levels raise every time you eat carbohydrates and to a lesser extent, protein, as they are converted into blood sugar. So after a main meal you can always expect a spike to some degree. This is partly why it's considered better to have 5 to 6 smaller meals spread throughout the day rather than 3 huge meals as they will create a much smaller insulin spike, as regardless of what they consist of, simply by being smaller portions they will have a smaller glycemic load and therefore result in lower insulin spikes that will clear quicker, and theoretically allow for less energy to be stored as fat after meals. As well as smaller portions, dietary fibre massively helps to prevent insulin spikes, by slowing down the digestion of all food, making you feel fuller for longer and allowing a much slower release of sugar into the blood.
Even with insulin spikes, it's the level of excess sugar/insulin in the blood that is the problem here, and the frequency of it being in excess, not the fact that sugar and insulin is in the blood. Insulin spikes can be used to good effect first thing in the morning and post workout when your body is most sensitive to insulin. Generally speaking however, especially when it comes to snacking, insulin spikes are best avoided or kept minimal as they can lead to that low blood sugar drowsy sensation that makes you feel hungry and crave more sugar. Also, frequent spikes cause your blood sugar and insulin levels to remain high for a longer period of time which, if done throughout the day everyday, can lead to accelerated body fat gain and health problems in the long run. The important thing is to try to minimise spikes brought on from continuous snacking on junk foods throughout the day. They have a very high glycemic load and are very high in calories serving you the perfect recipe for weight gain. They do little to appease hunger and if anything they just make you crave more of the same.
Exercise routines, such as The 4 Minute Max Outs, and a healthy diet, increase your insulin sensitivity and make you less prone to the adverse effects of insulin spikes and continuous high blood sugar.
Diabetes is a potentially fatal, rapidly growing illness in the western world. It comes in two forms, type 1 and type 2. Type 1 is genetic bad luck. The rapid growth in diabetes is exclusively in type 2 diabetes. This is due to the rapid and continual rise of obesity in the world. Obesity is caused by lack of the right kind of exercise and poor dietary choices over time in modern life. In other words, in the vast majority of cases, type 2 diabetes is fully avoidable.
If insulin sensitivity becomes too low (insulin resistance is too high) then type 2 diabetes occurs. This is when your cells can't utilise the insulin being produced efficiently and your pancreas cant produce the right amount of insulin to balance out the overly high levels of sugar in the blood. You are more susceptible to type 2 diabetes if you have high levels of visceral fat around your organs, the kind that makes your waistline expand and gives you that apple or beer belly shape. Fortunately, the condition can be lessened by the factors that would have prevented it in the first place, such as exercise and a healthy active lifestyle with less sugary processed foods. However, prevention, by eating healthily and doing HIIT routines such as The 4 Minute Max Outs to burn away that visceral fat and improve your insulin sensitivity before developing it, is always the best strategy.
Type 1 diabetes, whereby your pancreas stops producing insulin altogether, is much more unfortunate as it is not preventable. If you have type 1 diabetes, you will need to take insulin injections for life and make sure that your blood glucose levels stay balanced by eating a healthy diet, performing regular exercise and taking blood tests regularly.
Insulin and weight loss.
The other issue why insulin gets a bad press, is to do with weight loss. As said, high levels of insulin restrict the release of fat as energy whilst preserving and potentially increasing the levels of stored fat at the same time. To a certain degree, this is actually a good thing, as it enables it to perform its task of leveling blood sugar as efficiently as possible. However, it's bad if you eat way too much sugar and keep spiking your insulin as it will lead to too much fat being preserved and will cause blood sugar to be stored as fat at a much faster rate. As said, what is too much sugar for one can be fine for another depending on a persons insulin sensitivity and activity levels. But with this in mind you can see how people with a lower insulin sensitivity may find that eating too many carbohydrates makes it not only harder for them to lose body fat but also easier to gain it. But notice the word 'may'. Cut out high added sugar processed foods to reduce your blood sugar levels and do some high intensity exercise to use your blood sugar levels and create a healthy calorie deficit. You will likely still see a rapid difference in your body and a positivie change to your insulin sensitivity. If you use healthy nutritious carbohydrates to fuel HIIT routines, such as The 4 Minute Max Outs, or weight sessions, this is much less of a concern. These kinds of exercise allow your muscles to take in more blood sugar as glycogen, both relative to their size and as they grow in size, improving your insulin sensitivity massively at the same time. It's the level of excess sugar/insulin in the blood that is the problem here, and the frequency of it being in excess, not the fact that sugar and insulin is in the blood. Both blood sugar and insulin perform crucially important roles in your body and are not just desirable, but needed to be healthy.
Insulin is a metabolic switch that you turn on and off with what you eat and when you eat it. You control the switch. This is where the Glycemic Index and Glycemic Load of food play their part in creating a healthy balanced diet that can and should contain plenty of slow burning carbohydrates with fast burning carbohydrates consumed at the optimal times for your body. Breaking your food intake up into 5 to 6 smaller meals per day, as opposed to 3 larger meals, will also help keep insulin levels lower after each meal. Carb cycling, described further down, can also help reduce the fat storing effects of insulin too on days where you may not be training as hard.
Cutting out high added sugar processed foods is one of the best things you can do to lose weight as it will not only reduce your blood insulin levels considerably, but your calorie intake too, setting the scene for weight loss. Increasing your bodies insulin sensitivity is a key factor in losing weight long term. One of the best ways to do this is performing high intensity exercise, such as The 4 Minute Max Outs. Then as your weight drops from the calorie deficit created by your exercise and your muscles use and take in more glycogen, your insulin sensitivity will increase further again, allowing your weight to drop more and your muscles to use and take in more glycogen, improving your insulin sensitivity again and so forth, starting a positive cycle of good health.
You can use the effects of insulin to your advantage at key points of the day. Eating a higher glycemic load of carbohydrates first thing in the morning and post workout can make excellent use of insulin, although any carbohydrates are good also. Ensure you take some protein with it for best results. When you get out of bed and post workout is when you are most insulin sensitive as your glycogen levels will have depleted somewhat, particularly after an intense work out. The insulin spike signals your body cells to absorb all nutrients, blood sugar, and protein, helping refuel your glycogen stores as quickly as possible. You are virtually impervious to the negative side effects of insulin spikes at these times as your body sucks up all the much needed energy like a sponge. This is a great technique for speeding up recovery time. So when used strategically, insulin is actually a great tool for assisting muscle growth.
Depending on your size, taking in about 40 to 80 grams of carbohydrates as soon as you get out of bed will boost insulin and quickly restock your glycogen levels stopping any overnight muscle catabolism that may have set in. Given that a pint of milk has approximately 25 grams of carbohydrates and 20 grams of protein, and 2 slices of brown bread contain around 30 grams of carbohydrates, you may already be doing something along these lines with your morning breakfast.
Post workout, again depending on your size, around 40 to 80 grams of high glycemic load carbohydrates foods will spike your insulin, and along with 25 to 30 grams of protein will speed carbohydrates and protein into your muscles. Again, given that a jacket potato has around 60 grams of fast burning carbohydrates and a high GL, and that a tin of tuna has around 25 grams of protein, you may already be doing this simply by having your dinner soon after a workout.
Throughout the rest of the day, it is best to keep your glycemic load low to prevent insulin spikes and help keep insulin blood levels, and your energy levels, stable.
Carb cycling is a method of timing your consumption of carbohydrates in relation to your workouts to manipulate the effects of insulin wisely. Rather than stick to a static food ratio every day, carb cycling uses days of high, medium, and low carbohydrates to maximise fat loss. For instance, on rest or cardio days, you wont need as much energy so you can eat a lower percentage of carbohydrates and proportionately raise the percentage of fats and protein. On HIIT and strength training days you will need more energy so you can eat a higher percentage of carbohydrates and proportionately lower the percentage of fats accordingly.
On workout days, if you still needed to be low carb, you could also ensure you only eat carbohydrates at breakfast, pre workout and post workout when your insulin sensitivity is at its highest. This is something a body builder would do in the cutting phase whilst keep their training plan just as intense, and is not a diet plan to live off. Eating a high protein pre workout meal with slow burning carbohydrates around an hour before your workoutwould ensure your glycogen levels were stocked. Then eat a post workout meal with fast burning carbohydrates and protein within 30 minutes after the workout to maximise the use of insulin and improve your recovery time. 50 grams at each of these three meals would be just 150 grams per day and still help to prevent catabolism, power your workouts, and aid recovery, just by timing the consumption right. This is a temporary weight loss measure, not a healthy diet plan to live off.