Fats vs Carbs vs Proteins
The three macronutrients, their building blocks, and what makes fat unique.
You've heard a lot about fats, carbs, and proteins in nutrition. Let's break down what both food and you are made up of:
Sugars are single units (monosaccharides such as glucose, fructose and galactose) or pairs (disaccharides such as sucrose, table sugar, which is glucose + fructose, and lactose, milk sugar, which is glucose + galactose).
Starch is a plant's storage form: hundreds to thousands of glucose units linked together, which we digest back down into glucose. Note that animals store their own glucose as glycogen rather than starch.
Fiber is made of links our enzymes cannot cut, so it passes intact into the large intestine, where gut bacteria ferment it — producing, among other things, short-chain fatty acids.
Vitamins are organic molecules (carbon-based, made by living things) that we mostly cannot synthesize ourselves. Thirteen are considered essential, split by how they dissolve. The four fat-soluble vitamins — A (Retinol), D, E (Tocopherol) and K — travel with lipids and can be stored in the liver and fatty tissue. The nine water-soluble vitamins — C and the eight B vitamins — are not stored in any meaningful quantity and must be replenished regularly.
Minerals are inorganic elements. Unlike vitamins, they cannot be built or broken down by any living thing, so every atom of calcium or iron in your body was eaten. They are divided by the amount required: · Macrominerals, needed in gram quantities: calcium, phosphorus, potassium, sodium, chloride, magnesium and sulfur. · Trace minerals, needed in milligram or microgram quantities, most of them metals: iron, zinc, copper, manganese, iodine, selenium, molybdenum, chromium and cobalt.
Protein sizes: Average Human Protein: Measures around 375 to 450 amino acids in length. Peptides are essentially short chain or small proteins, consisting of 2-50 amino acids. One of the larger known proteins is Titin, found in our muscles, at around 34,350 amino acids.
Protein Action: Proteins are essentially mechanical machines. They have very specific geometric shapes, and can fold and unfold to perform specific tasks. Some proteins can even perform mechanical rotations. Proteins can combine to perform even more complex mechanical tasks, such as pumping.
Protein creation: An adult synthesizes roughly 300-400 grams of protein per day, demonstrating the sheer volume of protein synthesis occurring constantly — though most of that is built from amino acids recycled out of the body's own worn-out proteins rather than from food, since we only eat 50-100 grams a day. Every cell can create protein. The DNA contains genes which store sequences of Adenine (A), Thymine (T), Cytosine (C), or Guanine (G). These sequences define how the amino acids are placed together to create proteins. The DNA sends out messenger mRNA molecules with this information to the cell's ribosomes — the molecular machines that read the sequence and assemble the amino acid chain. Ribosomes float freely inside the cell, or attach to the cell's “endoplasmic reticulum” organelle, which handles proteins destined for export or for the cell's membranes.
Fats
Fats are mostly made up of fatty acids. However, fats can also include non-fatty acid lipids such as cholesterol molecules, fat-soluble vitamins including Vitamins A (Retinol), D, E (Tocopherol) and K, and hormones such as testosterone, estrogen, and cortisol. This project will focus on fatty acids.Carbs
Carbohydrates are molecules built from carbon, hydrogen and oxygen, and they come in three main forms: sugars, starch and fiber. All three are made of the same simple sugar building blocks — what separates them is how many units are chained together and whether our digestive enzymes can break those chains apart.Sugars are single units (monosaccharides such as glucose, fructose and galactose) or pairs (disaccharides such as sucrose, table sugar, which is glucose + fructose, and lactose, milk sugar, which is glucose + galactose).
Starch is a plant's storage form: hundreds to thousands of glucose units linked together, which we digest back down into glucose. Note that animals store their own glucose as glycogen rather than starch.
Fiber is made of links our enzymes cannot cut, so it passes intact into the large intestine, where gut bacteria ferment it — producing, among other things, short-chain fatty acids.
Nutrients
The body requires a set of vitamins and minerals in far smaller quantities. They act as the tools and switches that let the other molecules do their work.Vitamins are organic molecules (carbon-based, made by living things) that we mostly cannot synthesize ourselves. Thirteen are considered essential, split by how they dissolve. The four fat-soluble vitamins — A (Retinol), D, E (Tocopherol) and K — travel with lipids and can be stored in the liver and fatty tissue. The nine water-soluble vitamins — C and the eight B vitamins — are not stored in any meaningful quantity and must be replenished regularly.
Minerals are inorganic elements. Unlike vitamins, they cannot be built or broken down by any living thing, so every atom of calcium or iron in your body was eaten. They are divided by the amount required: · Macrominerals, needed in gram quantities: calcium, phosphorus, potassium, sodium, chloride, magnesium and sulfur. · Trace minerals, needed in milligram or microgram quantities, most of them metals: iron, zinc, copper, manganese, iodine, selenium, molybdenum, chromium and cobalt.
Water
Water is the single largest component of both food and the human body, and by molecule count it is not close: about 99 out of every 100 molecules in you is a water molecule, because water is tiny next to a protein or a fat. By weight, it makes up about 60% of an adult male's body weight and 55% of an adult female's, rising to around 75% in a newborn. That water is not evenly spread — blood plasma is about 90% water, muscle about 75%, the brain about 75%, bone about 30%, and stored fat only 10-20%, which is why leaner bodies hold a higher percentage of water. About two-thirds of it sits inside cells, and the remaining third surrounds them and fills the bloodstream.Proteins
Proteins are long chains of amino acid molecules arranged into specific shapes. There are potentially over 100,000 different types of proteins in the human body, with each type having specific roles and actions to perform. Protein roles include:- Structural: Provide shape and support (e.g., collagen in skin, bone).
- Enzymatic: Speed up chemical reactions (e.g., digestion).
- Hormonal: Act as chemical messengers (e.g., insulin).
- Transport: Carry molecules (e.g., hemoglobin carrying oxygen).
- Contractile: Enable movement (e.g., actin and myosin in muscles).
- Defensive: Protect against disease (e.g., antibodies).
- Receptor: Receive signals on cell surfaces.
- Storage: Store nutrients (e.g., ferritin storing iron).
Protein sizes: Average Human Protein: Measures around 375 to 450 amino acids in length. Peptides are essentially short chain or small proteins, consisting of 2-50 amino acids. One of the larger known proteins is Titin, found in our muscles, at around 34,350 amino acids.
Protein Action: Proteins are essentially mechanical machines. They have very specific geometric shapes, and can fold and unfold to perform specific tasks. Some proteins can even perform mechanical rotations. Proteins can combine to perform even more complex mechanical tasks, such as pumping.
Protein creation: An adult synthesizes roughly 300-400 grams of protein per day, demonstrating the sheer volume of protein synthesis occurring constantly — though most of that is built from amino acids recycled out of the body's own worn-out proteins rather than from food, since we only eat 50-100 grams a day. Every cell can create protein. The DNA contains genes which store sequences of Adenine (A), Thymine (T), Cytosine (C), or Guanine (G). These sequences define how the amino acids are placed together to create proteins. The DNA sends out messenger mRNA molecules with this information to the cell's ribosomes — the molecular machines that read the sequence and assemble the amino acid chain. Ribosomes float freely inside the cell, or attach to the cell's “endoplasmic reticulum” organelle, which handles proteins destined for export or for the cell's membranes.
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