From Fat to Fuel: Understanding the Energy Conversion Process

How is fat turned into energy to be used as fuel for individuals working to improve their health and physical abilities?

Fat Into Energy Conversion

Fat is an essential component of a diet that fuels physical activity, work, exercise, etc. Its calorie density is the highest of all nutrients, and fat’s unlimited storage capacity makes it the body’s largest energy reserve. Fat is essential for longer, slower, lower-intensity endurance physical activities and exercises like walking and cycling.

What Is Fat?

Everything eaten is made up of:

Macronutrients

• Protein
• Carbohydrates
• Fat

Micronutrients

• Vitamins
• Minerals

These are converted to energy, helping to fuel all bodily functions.

Dietary fat has been blamed for various health problems, but it is an essential nutrient for optimal health. The adipose tissue/stored fat provides cushion and insulation to internal organs, protects nerves, circulates vitamins A, D, E, and K through the body, and is the largest stored energy reserve. Stored body fat is different from dietary fat. Body fat is only stored when more calories are consumed than used from all foods, not just from dietary fats. There is an optimal level of body fat for health and regular physical and athletic activity.

Types

Researchers and scientists are learning more and more about body fat/adipose tissue and its roles in the body. Two well-known types are white fat and brown fat.

• Brown fat helps regulate body temperature. (Richard AJ. et al., 2020)
• White fat is responsible for energy storage and metabolic functions like insulin sensitivity.
• White fat can transition to brown fat under certain cold temperatures. (Rabiee A. 2020)
• Beige fat is another type that scientists are still learning about.

When Fat Is Burned

When fat is used as fuel, the fatty acids inside the fat cell are broken down and released into the system as water and carbon dioxide. (MacLean P. S. et al., 2015) The body uses the water for hydration, and the carbon dioxide is exhaled through the lungs. The remaining fat cell shrinks as it is depleted of its fatty acids. The fat into energy conversion also produces heat.

Fat for Fuel

Fat is the main fuel source for long-duration, low—to moderate-intensity physical activities and exercise like endurance sports. Even during high-intensity activities and training, where​ carbohydrates are the main fuel source, the body still needs fat to help access the stored carbohydrates or glycogen. Using fat to fuel activity includes three key components which include:

Digestion

• Fat is slow to digest and convert into a usable form of energy.
• The process can take up to six hours.

Transportation

• After the body breaks down the fat, it needs time to transport it to the working muscles before it can be used as energy.

Conversion

• Converting stored body fat into energy takes increased oxygen, requiring decreased physical activity and exercise intensity.

This is why timing when and how much fat is consumed is important for its full potential. Eating foods high in fat immediately before or during intense physical work activity or exercise is not recommended. First, the job, chore, or workout will be done before the fat can be used as energy. And second, it can cause uncomfortable gastrointestinal symptoms like nausea, vomiting, and diarrhea.

Fat Loss Optimization

For individuals trying to alter body fat composition, the most important thing is to adopt a safe and effective physical activity and exercise routine and to eat a balanced diet of nutrient-dense foods that provide adequate amounts of macronutrients, including dietary fat.

Macronutrient

Low-carbohydrate and high-fat diets, like the ketogenic and Paleo diets, all work on the same premise: Lower carbohydrate intake, high fat intake, and moderate to high protein intake lead to burning body fat as the primary fuel source while engaging in physical activity or exercising. There is some scientific evidence that long-term low-carb/high-fat diets are safe and may help improve metabolic risk factors for chronic disease. Some studies on these diets have shown them to be beneficial for performance in endurance sports, but several months of adaptation to a low-carb/high-fat diet are required for metabolic changes to occur. (Chang C. K., Borer K., and Lin P. J. 2017))

High-Intensity Interval Training

High-intensity interval training is an efficient way to convert fat to energy. In a study, overweight individuals were able to convert body fat to energy in half the time using HIIT vs. aerobic activity alone (Zhang H. et al., 2017). HIIT specifically converts visceral fat, typically white adipose tissue, often found in the midsection. (Mittal B. 2019) HIIT also helps increase muscle mass and resting metabolism. (Thyfault J. P. and Bergouignan A. 2020) However, any exercise regimen that helps increase muscle mass provides these beneficial effects.

Injury Medical Chiropractic and Functional Medicine Clinic

At Injury Medical Chiropractic and Functional Medicine Clinic, we focus on what works for you to relieve pain, restore function, prevent injury, and better the body. Through research methods and total wellness programs, individuals can condition themselves to excel in physical activity or sports through proper fitness and nutrition. Regarding musculoskeletal pain, specialists like chiropractors, acupuncturists, and massage therapists can help mitigate the pain through spinal adjustments that help the body realign itself. They can also work with other medical professionals to integrate a treatment plan to resolve musculoskeletal issues.

Integrative Medicine and Chiropractic Care

References

Richard, A. J., White, U., Elks, C. M., & Stephens, J. M. (2000). Adipose Tissue: Physiology to Metabolic Dysfunction. In K. R. Feingold, B. Anawalt, M. R. Blackman, A. Boyce, G. Chrousos, E. Corpas, W. W. de Herder, K. Dhatariya, K. Dungan, J. Hofland, S. Kalra, G. Kaltsas, N. Kapoor, C. Koch, P. Kopp, M. Korbonits, C. S. Kovacs, W. Kuohung, B. Laferrere, M. Levy, E. A. McGee, R. McLachlan, M. New, J. Purnell, R. Sahay, A. S. Shah, F. Singer, M. A. Sperling, C. A. Stratakis, D. L. Trence, & D. P. Wilson (Eds.), Endotext. www.ncbi.nlm.nih.gov/pubmed/32255578

Rabiee A. (2020). Beige Fat Maintenance; Toward a Sustained Metabolic Health. Frontiers in endocrinology, 11, 634. doi.org/10.3389/fendo.2020.00634

MacLean, P. S., Higgins, J. A., Giles, E. D., Sherk, V. D., & Jackman, M. R. (2015). The role for adipose tissue in weight regain after weight loss. Obesity reviews : an official journal of the International Association for the Study of Obesity, 16 Suppl 1(Suppl 1), 45–54. doi.org/10.1111/obr.12255

Chang, C. K., Borer, K., & Lin, P. J. (2017). Low-Carbohydrate-High-Fat Diet: Can it Help Exercise Performance?. Journal of human kinetics, 56, 81–92. doi.org/10.1515/hukin-2017-0025

Zhang, H., Tong, T. K., Qiu, W., Zhang, X., Zhou, S., Liu, Y., & He, Y. (2017). Comparable Effects of High-Intensity Interval Training and Prolonged Continuous Exercise Training on Abdominal Visceral Fat Reduction in Obese Young Women. Journal of diabetes research, 2017, 5071740. doi.org/10.1155/2017/5071740

Mittal B. (2019). Subcutaneous adipose tissue & visceral adipose tissue. The Indian journal of medical research, 149(5), 571–573. doi.org/10.4103/ijmr.IJMR_1910_18

Thyfault, J. P., & Bergouignan, A. (2020). Exercise and metabolic health: beyond skeletal muscle. Diabetologia, 63(8), 1464–1474. doi.org/10.1007/s00125-020-05177-6