This is by far the most confusing food group due to the amount of choices in our supermarkets, which contain carbs in many guises e.g sugars, wheat flour, other flours and starches. By choosing the right type of carbs (allowing for treats), in the right amounts and ideally at the right time, you can use carbs to your advantage in weight control and optimum health.
Why do carbs need to be controlled?
When you eat a big meal, which is loaded with carbohydrates (carbs), e.g. pasta, rice, bread, potatoes etc, it sends your blood sugar soaring. The body immediately releases the hormone insulin whose job is to move the sugar out of the bloodstream; sugar (glucose) is toxic in the blood; hence the reason why the body, with the help of insulin moves it from the bloodstream and transports it into body tissues e.g. muscle cells and the liver.
NB Carbs get broken down mainly into glucose, regardless of the type.
Insulin escorts glucose into muscle cells for immediate energy, but when the muscle cells don’t need it (e.g. you don’t burn enough energy through exercise and daily activity), it gets shuttled into the fat cells. That is why insulin is also known as the “fat storing hormone”.
NB Some glucose gets stored in the muscles and liver as glycogen for emergency needs. However the glycogen “tank” can only store so much, then the excess glucose gets coverted to fat and then stored, often referred to as “fat spiilover.”
Insulin does its work with the help of an enzyme called lipoprotein lipase (LPL), which is the “fat storing enzyme.” LPL takes triglycerides from the bloodstream, divides them into smaller parts (fatty acids), and then promptly helps store these fatty acids in your fat cells.
If insulin remains in the bloodstream, it effectively locks the doors to the fat cells; they won’t open up and you won’t burn fat until insulin levels come back down. Of course, the more you continue to eat the same high carb diet, the less your insulin levels go down. Now you can see how it is impossible to burn fat when you have high insulin levels in your blood.
How do you burn fat?
Insulin has a sister hormone, namely glucagon and it’s a critical component of your fat burning biochemistry.
When you need more energy and food isn’t available, glucagon is secreted from the pancreas. Its purpose is the exact opposite of insulin; glucagon enters the cells and signals the release of fat and does so with the help of a fat burning enzyme, namely hormone sensitive lipase (HSL).
Much like glucagon is the opposite of insulin, HSL is the opposite of LPL, the fat storing enzyme mentioned above. HSL breaks down triglycerides, the form of fat stored in your cells into fatty acids and glycerol, allowing them to be released into the bloodstream and burned for energy or excreted. This glucagon/HSL axis is what is called the “fat burning switch”.
Fat burning and weight loss/control won’t take place unless the fat burning switch, glucagon/HSL is turned “on”. The fat burning switch is in the “off” position as long as insulin levels are high. Insulin levels are high whenever blood sugar is high, and blood sugar is typically high in response to not only highly refined carb meals, but also high carbs in general.
Keep blood sugar in a nice, moderate range (a combination of fats and proteins does this) where it won’t trigger excess insulin. By keeping blood sugar and insulin down, you allow glucagon/HSL aka the “fat burning switch”, to work its magic.
If you want to trigger your “fat burning switch”, you have to learn to eat in a way that won’t trigger excess insulin. Fortunately, that isn’t that hard to do as the simple and tasty ideas are included in this book.
So when you do eat carbs, choosing the right types of carbs, in the right amounts and ideally at the right time, will allow you to use carbs to your advantage in weight control and optimum health. Let’s look at all three factors below.
The type is important due to insulin response, calories and level of nutrients. For example grains for the most part have a higher insulin response (risking fat storage) than most other carbs, they are calorie laden, which in itself is not the be all and end all; however they have little nutrition and actually contain opiod peptides, which makes them mildly addictive. Hence the term “carb cravings”. They also have low satiety i.e they don’t keep you feeling full for long compared to fats and proteins.
For the best types of carbs to eat, see under “carbohydrates” in the “Foods to eat” section above. Similarly for the worst carbs to eat, see under the “Foods to avoid (or keep to a minimum)” section above.
Amounts are important due to the fact that the average human can only use so much glucose (depending on energy expenditure) per day and store so much glucose (as glycogen) per day in the muscle and liver tisues. Once these two options have been exhausted, the body has no option other than to store the excess glucose as fat, often referred to as “fat spillover”.
In terms of the proportion of macronutrients in your diet, at least 23 high quality studies have confirmed that a high healthy fat diet (about 55%) with a moderate quantity of protein (about 25%) and lowish amounts of carbohydrate (about 20%), will give optimal results for health and weight control.
The daily carb amounts below are a rough guide to your overall ability to regulate your weight and attain optimal health. Obviously exact amounts depend on activity levels and metabolic differences.
You can also cycle your carb intake to coincide with your activitiy levels e.g. on a workout day, you could have 200g of carbs and on a non workout day, you could titrate down to 50g. For an explanation on why this is an effective way to eat for weightloss and/or weight control, see “Timing” below.
NB We are not talking about grams per weight of food type e.g 100g (by weight) of sweet potato contains 20g of carbs, so a medium sized sweet potato is about 350g and would contain 70g of actual carbs. See the “Carb values for common foods” table at the end of the book.
- 20g to 50g is akin to a ketogenic diet; hard to maintain, but you will burn lots of fat.
- 50g to 100g represents the weight loss sweet spot; you will find fat loss fairly easy.
- 100g to 150g will give you (in most cases) effortless weight maintenance; you will maintain body composition.
- 150g to 300g will cause insidious weight gain; you will store more fat, leading to obesity.
- 300g and above represents an immediate danger to your health.
It is best to eat the bulk of your carbs post workout or on active days, since your insulin senstivity is at it’s highest i.e. your body will process carbs more efficiently, allowing them to be used for immediate fuel and glycogen (stored glucose), lowering the chance of fat storage.
For example on workout days, you opt for a meal with sweet potato and on non workout or inactive days, you would be better opting for fibrous vegetables in place of starchy carbs with your protein e.g. chicken or salmon with broccoli (lots of) or fish with cauliflower cheese (lots of).