Eat What’s Right for Your Body Type

Although there are government guidelines regarding the recommended quantity of macronutrients that we all should be eating, there are actually three different macronutrient recommendations one could choose to follow, depending on how your body burns.

If your body tends to store fat easily, you will need to eat a different amount of carbs, protein and fat to someone else who burns their food slowly and rarely stores fat.

During the process when food is broken down, oxidation occurs, converting carbs into glucose. This is released in the blood, stimulating the pancreas to release the hormone insulin to mop up the glucose(sugar) from the blood. This sugar is not being utilised by the body for energy and it needs to be stored in the cells as fat.

Depending on our body types, we oxidise foods in different ways. This can explain why certain diets work on celebs or our friends but not on us.

To eat correctly for your body type, it is important to understand which type you are. This can help you consume the optimum nutrients to achieve maximum results.

Fast oxidisers store fat easily. This is because the nutrients in their food are broken down very so rapidly that the carb content is broken down to glucose and released into the blood almost at once. This sudden increase in blood sugar quickly causes vast amounts of insulin to be released to mop up the extra glucose, which the body then stores as fat in the cells.

The more carb content in a fast oxidiser’s food, the more energy will be available to the body right away, and so more fat is stored.

The hormone insulin works quickly to remove the glucose from the blood, causing a dramatic rise and inevitable fall in blood sugar levels that result from fast oxidation. This is called a sugar crash. For a fast oxidiser, foods with high carb ratios will therefore cause fatigue, carb cravings and fat storage.

Fast oxidisers would benefit from consuming meals with more proteins and fats in order to slow down their rate of oxidation and insulin release, and to better promote stable blood sugar and sustained energy levels.

On the other end of the scale, slow oxidisers burn through the nutrients in their food slowly and do not release the glucose from carbohydrates into the blood quickly enough, which means that they do not get converted into glucose, and energy production and availability are delayed. They will be less likely to store fat.

The presence of protein and fat in the meal will slow down the rate of oxidisation even further, so a slow oxidiser should eat a higher ratio of carbs in order to gain an increase in energy as storing fat is far less of an issue.

As you have probably guessed, balanced oxidisers fall right in between the two. Ideally meals should contain equal quantities of protein, fat, and carbs in order to obtain the maximum amount of nutrients and energy from the foods.

The three main body types are shown below with the ideal macronutrient percentage of your total daily food intake, and per meal.

1. Fast oxidisers: 20%carbs, 50% protein, 30%fat.
2. Slow oxidizers: 60%carbs, 25%protein, and 15%fat.
3. Balanced oxidizers: 40%carbs, 30%protein, and 30%fat

Insulin Spikes

The hormone insulin is secreted by the pancreas in order to reduce sugar levels in the blood. An insulin spike is created when you eat foods with a high glycemic index (GI),that is a large amount of simple sugar. The simple sugars enter the bloodstream and insulin is needed to store the sugars as glycogen in the liver and the muscles. Insulin also stops protein breakdown after a workout and increases amino acid uptake into the body.

Muscles have a high demand for glucose and utilise an enzyme called hexokinase. This is found in skeletal muscle and promotes glucose uptake independently of blood glucose levels. Hexokinase has a high affinity for glucose, which allows muscle to take up glucose from the blood even when blood glucose levels are low. When the glucose reaches the muscle, it remains there and is not released back into the bloodstream. Thus skeletal muscles do not need insulin in order to obtain much needed glucose, however any insulin secreted will cause additional glucose to be taken up.

Another enzyme called glucokinase found in the liver works when levels of glucose in the blood rise. Unlike skeletal muscle, the liver can release glucose when the cells require it. This enzyme only acts in the presence of high blood glucose levels.

Exercise, especially resistance training, has been shown to increase glucose uptake for skeletal muscle in the absence of insulin, so that you do not necessarily need to consume simple sugars in your post workout meal in order to cause an insulin spike so that your muscles will uptake glucose.

While insulin will certainly enhance the anabolic response of a meal post workout, glucose is not actually needed since skeletal muscle is already able to uptake glucose in the absence of insulin after a workout.

For optimum results however, consuming a meal post workout with simple sugars and protein, will bring glucose into the muscles and allow an increase the uptake of amino acids into the body.

Insulin not only controls the uptake of glucose into cells but also has an impact on fat oxidation and storage. When blood glucose and insulin levels are low, fat is the main fuel burned for energy. This is why a low intensity cardio workout on en empty stomach before breakfast can be so effective at tapping into the fat stores when glucose and insulin levels are low. But when blood glucose and insulin levels are high, fat burning is blunted and glucose oxidation is elevated.

When the body senses there is glucose in the bloodstream, it wants to return blood glucose levels back to a homeostatic level. In order to do this the body must get rid of the glucose, which is accomplished by increasing glucose oxidation and storage.

Since the body is focusing on storing nutrients, it would not make sense for fatty acids to be released from adipocytes because they would not be burned. Therefore it is important that blood glucose levels return to normal quickly so the oxidation of fat can once again become the primary source of energy. This can be done by controlling your carbohydrate intake and controlling your insulin secretion by consuming less high GI foods; simple sugars, and more slow release low GI complex carbohydrates.

In the presence of high blood glucose and insulin, hormone sensitive lipase (HSL), the enzyme that catalyzes the liberation of fatty acids from fat cells) cannot act on stored fat. Therefore, fatty acids cannot be liberated from fat cells and fat oxidation is put on the backburner while glucose oxidation and storage is made a priority. Insulin is termed an anti-lipolytic hormone because it blocks lipolysis – the breakdown of stored triglycerides fat into fatty acids.

In addition to blunting fat oxidation, insulin secretion stimulates fat synthesis in the liver and increases fat uptake by fat cells.

Insulin spikes can also be caused by prolonged periods of sitting, such as in an office environment. Studies show that a short walk to the bathroom or the water cooler can alleviate this by getting away from your desk every 20mins after one hour of sitting still.

As useful as insulin spikes are at aiding the uptake of amino acids into the body, a large number of spikes throughout the day can cause the storage of fat and decrease fat oxidation. Regular exercise and a diet consisting of complex carbohydrate allows the body a steady flow of glucose without spiking the blood and increasing fat storage.

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