Food becomes energy when your body breaks it down into sugars, fats and amino acids and burns them to recharge ATP (adenosine triphosphate), the molecule that actually fuels every cell. Carbohydrates recharge ATP fastest, fat releases far more energy but slowly and only with plenty of oxygen, and protein contributes very little.
Optimizing fat burning while simultaneously building muscle should be the goal of any effective exercise program; the critical linkage between exercise and the food we eat is ATP. This article describes the importance of understanding what ATP is, and how different foods are converted to ATP, and when different fuels (protein, carbohydrate, or fat) are used for energy. Understanding these concepts provides the blueprint for the Live Health Protocol diet and exercise guidelines.
I frequently talk to patients about the foods they eat, and how it impacts their health. I think it’s very important to understand that converting food to usable energy is far more than simply chewing big pieces of food, which are digested into small pieces, and used directly by the cells. Your body does not directly take the food particles it consumes and transfers them to your cells for metabolism. It converts these particles to fundamental substrates, which are then converted to ATP (adenosine triphosphate), which is the actual fuel for your cells.
(Other substrates are used for structural growth and for cofactors, as well as immune recognition purposes; but the apple you eat does not become a little apple that your cells consume, it instead converts to sugars, proteins, and fats which are metabolized to ATP, which power your cells.)
The universal currency for life is ATP, the energy-carrying molecule found in the cells of all living things. ATP functions like a tiny battery debit card. An ATP molecule consists of adenosine and three negatively charged inorganic phosphate groups when it is fully charged and ADP (adenosine diphosphate) when it has released its energy and has only two phosphates.
Recharging ADP to ATP requires fuel substrates, which is the converted food that you eat, whether it be protein, carbohydrate, or fat. The exact recharging is coupled to the molecular destruction of Carbon bonds, similar to gasoline combustion in your car.
The recharging of ADP to ATP is what couples the food you consume to usable energy, the discharging of ATP to ADP transfers energy to usable cellular function for either chemical or mechanical reactions. Available ATP (and Phospho Creatine- a related Phosphate storage bank in muscle) is depleted within 15 seconds of vigorous exercise.
Which foods does your body turn into energy?
There are three significant fuel sources or substrates of energy to reform ATP from ADP.
How do carbohydrates become energy?
Carbohydrates are metabolized to glucose, which quickly regenerates ADP to ATP through a process called glycolysis. Consumed carbohydrates are directly available as glucose, or excess consumed carbohydrates are stored in muscle and liver as glycogen for later reconversion to glucose. (Excessive carbohydrates in the presence of insulin are also converted to fat in fat cells.) Use of carbohydrates for energy does not require large amounts of oxygen and can occur even during anaerobic conditioning. Production of lactate and lactic acid occur with use of carbohydrates for fuel. Available carbohydrates provide energy to recharge ATP for the first 45-60 seconds of high intensity therapeutic exercise.
How does fat become energy?
Fat is a slow energy release form, typically stored in fat cells. Lipolysis is the term used to describe the breakdown of fat (triglycerides) into the more basic units of glycerol and free fatty acids, which then undergo beta-oxidation. Combustion of fatty acid molecules produces significantly more ATP, compared to glucose molecules. However, because fatty acids consist of more carbon atoms than glucose, they require more oxygen for their combustion. Fatty acids are oxidized by most of the tissues in the body; except, the brain, red blood cells, and the adrenal medulla. It is a huge storage reservoir, but is too slowly released for immediate energy utilization. Lipolysis provides energy after the first 60 seconds of exercise, but only effectively in the presence of large amounts of oxygen.
Does protein give you energy?
Protein can also be used as an energy source, but it must first be broken down to amino acids before being converted to glucose. Protein is thought to make only a small contribution (< 5%) to energy production, but up to 18% of total energy requirements during long strenuous activity, sometimes characterized as rhabdomyolysis.
Frequently asked questions
What foods give you energy immediately?
Carbohydrates. They break down to glucose, which recharges ATP fastest through a process called glycolysis and does not need large amounts of oxygen. The ATP already stored in your muscles runs out within about 15 seconds of vigorous exercise, and available carbohydrates then carry you through the first 45 to 60 seconds of high-intensity effort. Fat takes over after that, but only when plenty of oxygen is available.
Is food a form of energy?
Food holds energy in its carbon bonds, but your cells cannot use it directly. The apple you eat does not become a little apple your cells consume. Your body converts it to sugars, fats and amino acids, then breaks those carbon bonds, much like gasoline burning in a car engine, to recharge ATP. ATP is the fuel every cell actually spends.
What foods don’t give you energy?
Protein gives the least. It must first be broken down into amino acids and then converted to glucose before it can recharge ATP, so it supplies less than 5% of your energy under normal conditions. During long, strenuous activity that share can climb to 18%. Carbohydrates and fat do the real work of refueling your cells.
