Do you know what macronutrients are? The primary nutrients and energy provision for fitness enthusiasts – muscle-building nutrition for the weak, thin, and elderly.
The nutrients we consume are broken down in the body to produce specific amounts of energy, commonly referred to as calories. Calories are provided by macronutrients, micronutrients, vitamins, and minerals consumed in the diet. Today, let’s focus on macronutrients, while micronutrients encompass various aspects that we will delve into later.
Macronutrients: Just like macroeconomics in economics, macronutrients, also known as major nutrients, refer to a category of foods that need to be consumed in large quantities in the diet. These are the carbohydrates, proteins, and fats that are commonly eaten, widely known, and universally present. In equal quantities, carbohydrates yield 4 kilocalories of energy, proteins yield 4 kilocalories, and fats yield 9 kilocalories. Additionally, fat tissue derived from the conversion of carbohydrates to fat can yield 3.27 kilocalories, while alcohol yields 7 kilocalories. It’s important to note here: carbohydrates and proteins yield the same amount of energy, while fats and alcohol yield the highest amount of energy.
Did you know? One molecule of glucose can generate 36 adenosine triphosphate (ATP) energy molecules, while one molecule of fatty acid can produce 129 ATP energy molecules? Despite providing more energy than glucose, the process of metabolizing fatty acids into ATP energy is slower and less efficient. Although fatty acids are present in higher concentrations in skeletal muscle, their uptake only increases when the supply increases. So, glucose can provide you with energy at a rapid rate, while fatty acids can only provide you with long-term and endurance-based energy.
Energy balance is assessed by comparing total calorie intake over a 24-hour period with total energy expenditure. For fitness and nutrition professionals, a straightforward indicator of this balance is changes in body mass. Weight gain indicates an excess calorie intake compared to expenditure, while weight loss indicates fewer calories consumed than expended. Weight loss management should pay attention to total calorie intake.
Carbohydrates, a macronutrient, can be as perplexing as fats for many. They provide a significant energy source for the body but require balance with other macronutrients for a healthy diet. There are two main types: simple carbohydrates (sugars) and complex carbohydrates (starch).
During the digestion process, simple carbohydrates are broken down into monosaccharides and disaccharides. The primary monosaccharides found in food include glucose and fructose. Glucose is widely present in fruits, sweet corn, corn syrup, specific roots, and honey. Fructose is predominantly found in fruits and table sugar. Although both are common monosaccharides in the diet, they serve as unique energy sources. Glucose is rapidly and efficiently utilized by muscles, while fructose undergoes slower metabolism, requiring conversion in the liver.
Glucose is one of the most common monosaccharides in the diet and directly affects blood sugar levels depending on the type of carbohydrates consumed. Unlike glucose, fructose does not cause rapid changes in blood sugar levels, making it more popular. Before being utilized by most cells, fructose must be converted into glucose in the liver, which is why blood sugar rises more slowly after consuming fructose. During low blood sugar and exercise, a rapid energy boost requires timely replenishment of glucose. For diabetic patients, consuming slowly metabolized fructose and starchy polysaccharides is necessary to gradually increase blood sugar levels.
Disaccharides play a role in providing energy within the human body. They are broken down into monosaccharides during the digestion process, absorbed into the bloodstream, and supplied to various cells for energy metabolism and sustaining life activities. Disaccharides are found in many foods, especially those rich in carbohydrates. Common food sources include fruits, vegetables, grains, and dairy products. For example, sucrose is found in sugarcane, sugar beets, and sugar oranges; maltose is present in barley, malt, and beer; lactose is found in dairy products such as milk, yogurt, and cheese.
Complex carbohydrates are carbohydrates formed by the chemical bonding of multiple monosaccharide molecules. They are primarily found in many natural foods, including grains (such as rice, wheat, oats), legumes (such as soybeans, lentils, peas), root vegetables (such as potatoes, carrots), starches, and some fruits (such as bananas, apples).
After being digested and absorbed in the human body, complex carbohydrates gradually release monosaccharide molecules, providing sustained and stable energy supply. They are one of the main sources of energy for the body and also provide dietary fiber, which helps promote digestive system health. Due to the slow release of monosaccharides, complex carbohydrates can also regulate blood sugar levels, lower cholesterol, and prevent the occurrence of diseases such as obesity and diabetes, which is why people are advised to consume them more.
Proteins, comprising macromolecules and polypeptides are built from amino acids linked by peptide bonds. Essential for cell growth, maintenance, and repair, as well as enzyme and hormone production, proteins make up most of the dry weight of body cells.
Amino acids, categorized by dietary necessity, include essential, non-essential, and conditional types. Essential amino acids must be obtained from diet, while non-essential can be synthesized by the body. Conditional amino acids are vital in specific situations. Although a balanced diet typically provides all necessary amino acids, muscle growth can be limited by a shortage of certain amino acids, such as leucine, even with adequate overall protein intake. For individuals with dietary restrictions or vegetarians, they need to obtain the deficient amino acids in their diet through other means.
For example, a client consumes 100 grams of protein per day, with all the essential amino acids in equal amounts. Their body will use a percentage of leucine for energy during a tough training session which reduces the amount of leucine available for growth and repair of muscles after training. Even if the body has access to adequate amounts of the other amino acids, this diminished leucine supply limits muscle growth. When the leucine supply runs out, protein formation will be negatively affected because leucine is an essential amino acid.
THE QUALITY OF PROTEINS：Not all proteins are nutritionally equal. Some include more essential amino acids and are better suited for growth and muscle development.
Proteins also play a crucial role in cellular communication, present in both plant and animal cells. While plants contain protein, some may be bound in cellulose, limiting human digestion and protein accessibility. Fitness enthusiasts, individuals with weak physique, those who are lean, and elderly individuals should consume a balanced diet rich in meat-based protein to increase muscle nutrition and reduce muscle atrophy.
Fats, also known as lipids, this macronutrient plays an important role in human physiology and is just as important as proteins and carbohydrates.
There are two main types of nutritional fats: saturated and unsaturated. Saturated fats, found in solid form at room temperature, can raise LDL cholesterol levels and are often associated with increased risk of heart disease. Unsaturated fats, derived from plants, remain liquid at room temperature and play vital roles in cell structure, growth, and hormone production.
Fatty acid length affects metabolism, with shorter chains being easier to metabolize for energy. Fats also contribute to hormone production, influencing processes such as human reproduction through the synthesis of prostaglandins and steroid hormones from cholesterol and fatty acids. Here’s a reminder for sisters and brothers: Being too lean without adequate fat protection can affect sexual function, reproductive capacity, and the ability to resist diseases in old age.
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