Nutrition is absolutely paramount to achieving any sustained level of wellness. If wellness were a house, nutrition would be the foundation. Many of us already accept this to be true, yet most of us remain generally confused by what we should be eating. This is understandable as results from nutritional studies are often paraded around news outlets and blogs without going into any depth about the study’s design, context or its limiting factors.
Unlike other scientific experiments which focus on uncovering causative relations via double blind, randomly controlled trials, nutritional studies often fall short because of the inherent difficulty in accurately tracking what people eat. Additionally, to truly understand chronic disease formation, long term longitudinal studies are needed. These are both costly and ripe for inaccuracies as they often rely on self reported and survey data. As a result, many nutritional studies focus on epidemiological studies which can only uncover correlations and pose problems for limiting confounding variables and accounting for individual genetic differences.
Knowing this, is it any wonder we see such conflicting study results in the news? One study supports a low carbohydrate high fat diet while another supports the exact opposite. One study suggests cholesterol and saturated fat are perpetrators of chronic disease while another claims it’s refined carbohydrates and sugar. We’re pulled in every which direction because many of us don’t have a strong grasp on the basics of nutrition and the biochemistry of the human body.
The goal of this blog post is to start at ground zero. To revisit the basics of nutrition to help give you a more solid footing so you’re better equipped to handle the health headline storms. We won’t be tackling what you should be eating just yet, as we’ll save that advice for a later date. For now, let’s buckle up and dive into some nutrition 101.
All the food we eat is comprised of micronutrients and macronutrients. Macronutrients are the structural and energy-giving caloric components of our foods that most of us are familiar with. They include carbohydrates, fats and proteins. Micronutrients are comprised of vitamins and minerals which are required in small quantities to ensure normal metabolism, growth and physical well‐being.
These are essential organic nutrients, most of which are not made in the body, or only in insufficient amounts, and are mainly obtained through food. An organic compound contains carbon. When an organism (living thing) cannot produce enough of an organic chemical compound that it needs in tiny amounts, and has to get it from food, it is called a vitamin.
Sometimes the compound is a vitamin for a human but not for some other animals. For example, vitamin C (ascorbic acid) is a vitamin for humans but not for dogs, because dogs can produce (synthesize) enough for their own needs, while humans cannot.
When intake is inadequate, vitamin deficiency disorders are the consequence. Luckily, we don't live in 18th century America anymore and none of us suffer from vitamin deficiencies like scurvy. Although vitamins are only present and required in minute quantities, compared to the macronutrients, they are as vital to health. There are 13 known vitamins today.
Water Soluble Vs Fat Soluble Vitamins
Vitamins can be further broken down into two categories: those that are water soluble and those that are fat soluble. Water soluble vitamins (Bs and C) are vitamins that our bodies do not store. These vitamins dissolve in water when they are ingested, then go into the bloodstream.
The body keeps what it needs at that time, and excess amounts are excreted in the urine. Since they can’t be stored, everybody needs a continuous supply of water soluble vitamins in order to stay healthy.
The fat soluble vitamins (A, D, E and K) are soluble in lipids (fats). These vitamins are usually absorbed in fat globules (called chylomicrons) that travel through the lymphatic system of the small intestines and into the general blood circulation within the body. These fat soluble vitamins, especially vitamins A and E, are then stored in body tissues.
Fat soluble vitamins, once they have been stored in tissues in the body, tend to remain there. This means that if a person takes in too much of a fat soluble vitamin, over time they can have too much of that vitamin present in their body. Conversely, those on low fat diets need to make sure they are getting enough fat to aid vitamin absorption.
As athletes, vitamins are particularly important because vitamins C and E serve as the body’s primary source of antioxidants. Antioxidants help repair cells from free radical damage which is induced from strenuous exercise.
These are inorganic nutrients that also play a key role in ensuring health and well‐being. They include the trace elements copper, iodine, iron, manganese, selenium and zinc together with the macro elements calcium, magnesium, potassium and sodium. As with vitamins, minerals are found in small quantities within the body and they are obtained from a wide variety of foods.
Fun fact. Because matter can be neither created nor destroyed, the calcium in your bones and the iron in your blood has been reused and recycled by millions of other organisms since the formation of planet. Said differently, the same calcium in your bones was once the calcium in dinosaurs. Yes, you are made of the same shit as dinosaurs. Now, don't ever question your ability to get radical in the gym.
As athletes, minerals are particularly important as they aid in transportation of nutrients from our bloodstream to our cells. Electrolytes, which are added into every sports drink ever, are nothing more than charged minerals.
No single food contains all of the vitamins and minerals we need and, therefore, a balanced and varied diet is necessary for an adequate intake.
As mentioned above, macronutrients provide our bodies with energy. They also power a whole host of vitally important biochemical systems. All three are equally important and required for a healthy body.
So, how exactly does our body utilize each macronutrient once we eat it? Before answering that question, let’s first understand what each macronutrient does at a high level.
Carbohydrates, stored in our muscles and liver as glycogen, is what powers our cells. Our bodies can convert proteins and fats to glucose, but the process is inefficient. Carbs are our primary energy source and comprise our greatest caloric needs. Additionally, carbs fuel the brain and central nervous system which helps aid in coordination, balance and memory. Our bodies have limited capacity for storing carbs, which is why we need to consume them frequently.
1 gram of Carbohydrates = 4 Calories
Proteins are the building blocks of our bodies. Protein consists of combinations of structures called amino acids that combine in various ways to make muscles, bone, tendons, skin, hair, and other tissues. In fact, over 10,000 different proteins are in the body. Proteins are also vital to regulating our hormonal, metabolic and transport systems. Finally, proteins are involved in maintaining the correct acid/base balance inside the body.
1 gram of Protein = 4 Calories
Fats serve three main purposes in the body. First, as a reserve energy source when our muscle glycogen is depleted, our bodies convert fat to glucose via a process called gluconeogenesis. Secondly, fat helps insulate the body, maintaining a consistent body temperature and protecting vital organs from sudden impacts. Finally, as mentioned above, fat aids in vitamin absorption for specific vitamins (A, D, E and K).
1 gram of Fat = 9 Calories
From the moment a bite of food enters the mouth, each morsel of nutrition within starts to be broken down for use by the body. In fact, amylase, an enzyme in our saliva, goes to work immediately, breaking down starch to glucose before the food even hits our stomachs. This process of converting food into components that can be used for the body's basic processes is called metabolism and it encompasses a whole series of chemical reactions. Proteins, carbohydrates, and fats move along intersecting sets of metabolic pathways that are unique to each major nutrient. Fundamentally, if all three nutrients are abundant in the diet, carbohydrates and fats will be used primarily for energy while proteins provide the raw materials for making hormones, muscle, and other essential biological equipment.
Proteins in food are broken down into pieces (called amino acids) that are then used to build new proteins with specific functions, such as catalyzing chemical reactions, facilitating communication between different cells, or transporting biological molecules from here to there. When there is a shortage of fats or carbohydrates, proteins can also yield energy.
Fats typically provide more than half of the body's energy needs. Fat from food is broken down into fatty acids, which can travel in the blood and be captured by hungry cells. Fatty acids that aren't needed right away are packaged in bundles called triglycerides and stored in fat cells.
The carbohydrates in food are digested into small pieces, either glucose or a sugar that is easily converted to glucose (fructose or galactose) that can be absorbed through the small intestine's walls. After a quick stop in the liver, glucose enters the circulatory system, causing blood glucose levels to rise. The body's cells gobble up this mealtime bounty of glucose more readily than fat.
Once the cells have had their fill of glucose, the liver stores some of the excess for distribution between meals should blood glucose levels fall below a certain threshold. If there is leftover glucose beyond what the liver can hold, it can be turned into fat for long-term storage so none is wasted. When carbohydrates are scarce, the body runs mainly on fats. If energy needs exceed those provided by fats in the diet, the body must liquidate some of its fat tissue for energy.
Understanding the body’s metabolic process and how it utilizes micro and macro nutrients should give you a stronger foundation for assessing health claims. In the next blog post, we’ll dive into energy creation within the body and what you should be eating to fuel athletic success!