How Are Macronutrients Metabolized
Nutrient metabolism occurs when nutrients in your diet are absorbed into your blood and tissues to be used for growth, maintenance, or healing of any part of your body. The way these nutrients are organized and how many you eat matter!
Many people get this concept only at meal times because that is where most nutrition studies occur. But beyond eating, our bodies also use certain foods as sources of fuel to function.
Certain foods have a higher proportion of some macronutrients (carbohydrates, fat, and protein) than others. These “source” foods help provide those needed energy to perform activities such as thinking, moving, talking, and functioning socially.
We usually refer to them as “meals” but they can be snacks or anything else that contains enough food to meet your needs for the day. Some examples include carrots, berries, almonds, yogurt, etc.
What if we could improve our overall health by choosing more source-foods? This would mean consuming more vegetables and fruits and less amount of processed carbs and fats. That’s why it’s important to know what happens to carbohydrates, lipids, and proteins after they enter your system.
There are several types of metabolic pathways, or ways cells use to process nutrients. What kind each individual has depends on their genetics and lifestyle habits. Having an understanding of which ones affect health can help you identify potential risk factors and find strategies to promote optimal wellness.
Glycemic index
The glycemic index (GI) is an indicator of how quickly glucose, or blood sugar, is absorbed into your body. There are several different GI scales, but most compare food with glucose as a base and assigns a numerical value to how much glucose the sample contains and how fast it is metabolized.
The higher the number, the faster the absorption and metabolism of the test food. Foods that contain lots of carbohydrates are usually very high in the GI scale.
Carbohydrates found in grains, fruits, and some vegetables make up the vast majority of our daily carbs intake. Because they’re so rich in carbohydrate, they have a high GI.
Conversely, foods that contain little to nocarbohydrate break down more slowly because they don’t raise blood glucose levels as rapidly. These are referred to as low-glycemic-index (LGI) foods.
Studies show that eating LGI foods can help reduce insulin resistance and triglyceridelevels in patients with type 2 diabetes and/or obesity.
Glycemic load
Glycemic index (GI) is a way to classify foods according to their effect on blood glucose. Foods with higher GI’s can increase your blood sugar levels more quickly, whereas low-GI foods may have other health benefits, such as lowering LDL or “bad” cholesterol.
The glycemic index was first published in 1981 by Dr. David Jenkins at the University of Toronto. He assigned numbers to different types of carbohydrate containing foods and measured how much glucose they induced in his research subjects. The GI then becomes a measure of how rapidly carbohydrates in a given food will raise blood glucose levels.
A high GI means that the tested sample raises glucose levels faster than normal – therefore it has a higher value. A white bread product made using refined grains would be higher intensity than an oat meal bar that takes longer to chew and swallow. Both contain about the same amount of carbs, but one could potentially cause a bigger insulin response due to the type of starch consumed.
Cardiovascular disease
Another major cause of death in developed countries is cardiovascular disease (CVD). Heart diseases are very common, with more than half a million people dying each year from heart attacks or strokes.
Many different factors contribute to atherosclerosis, including high cholesterol levels, inflammation, and clotting too much due to excessive blood glucose or insulin.
Atherosclerotic plaques can build up in arteries anywhere within the body where blood flows, limiting or even blocking blood flow and causing tissue damage. If enough damage occurs, it may lead to amputation of limbs or death.
Some studies suggest that eating diets rich in omega-3 fats may help reduce risk by lowering LDL (“bad”) cholesterol and reducing inflammation. Others have not found such benefits, however.
Researchers also suspect fiber may play a role in protecting against CVD.
Metabolic syndrome
People with metabolic syndrome have insulin resistance, which is when your body does not respond well to the hormone called insulin. Insulin helps regulate blood glucose levels in your blood.
When you eat foods that are high in carbohydrates or fat, your pancreas releases more of the hormones needed to process them. This happens because carbs and fats need insulin to be processed in your liver and muscles.
However, people with insulin resistance don’t produce enough insulin, so their bodies cannot use it effectively. When this happens, blood sugar may stay too low, leading to symptoms such as hunger, light sleep (sleepy mode), nervousness and irritability.
Furthermore, individuals who suffer from insulin resistance often get chronic health conditions like hypertension (high blood pressure) or atherosclerosis (hardened arteries). These can lead to heart disease and stroke.
There are several risk factors for developing insulin resistance. Genetics, lifestyle choices, obesity, stress and nutritional deficiencies can all play a part.