If you’re someone who often struggles with weight management, low energy, brain fog, or sleep imbalances, improving your metabolic flexibility may be the game-changer you’re looking for.
Metabolic flexibility is the ability of the mitochondria, your cells’ powerhouses, to efficiently switch between using carbohydrates and fats as fuel sources depending on their availability and your body’s energy demands.
This adaptability is crucial for consistent energy levels, weight control, and overall metabolic health. Metabolic flexibility addresses the root cause of many health issues [1], offering a whole-body approach to wellness. Unlike quick-fix diets, it’s a sustainable way of life focused on balance, not perfection.
Everyone’s metabolism is unique, so understanding yours will help you integrate healthy habits to improve your health and set yourself up for long-term success. This powerful shift will stay with you for life, transforming your overall well-being.
Metabolic inflexibility is when the body cannot efficiently switch between using carbs or fats for fuel [1].
Being metabolically inflexible can lead to weight gain, low energy levels, brain fog, and an increased risk of metabolic syndrome like insulin resistance.
When you are metabolically inflexible, your body can become overly dependent on carbohydrates as a primary energy source rather than switching to fat burn when needed.
Constantly relying on carbs for energy can cause frequent spikes in blood sugar after meals, releasing more insulin. Over time, the cells can become desensitized to insulin, leading to insulin resistance [2]. When cells become insulin resistant, glucose can’t enter cells easily, leaving high glucose levels in the bloodstream. The body continues to rely on carbs while fat stores remain untapped.
Both metabolic inflexibility and insulin resistance can lead to weight gain, especially around the abdomen, as the body stores excess fat and struggles to burn it.
Here are 7 key benefits of metabolic flexibility, according to our Lumen metabolic coaches.
Metabolic flexibility facilitates weight loss by optimizing your mitochondria’s use of stored fat as an energy source. This efficiency is partly due to improved mitochondrial health, which is central to switching between fuel sources.
When your body is metabolically flexible, it can easily access fat stores during periods of fasting, exercise, or low carbohydrate intake [1]. This ability to burn fat is essential for weight loss, as it helps reduce body fat while providing sustained energy without the need for constant eating or snacking.
Metabolic flexibility enhances athletic performance by allowing the body to efficiently shift between fuel sources depending on the energy demands of the activity. Boosting metabolic flexibility to shift to carb burn when needed could help you lift heavier weights and build more muscle.
Moreover, by improving how the body accesses and utilizes stored carbohydrates like glycogen, athletes can experience reduced fatigue and improved stamina, ultimately leading to better overall athletic performance [3].
Metabolic flexibility also helps the mitochondria to move from carb burn to fat burn overnight. Because the mitochondria’s preferred fuel source during rest is fat burn, this helps with getting quality sleep and properly recovering after workouts, which helps prevent injuries and improves athletic performance.
Switching smoothly between burning carbs and fats for fuel ensures steady energy all day. This prevents fatigue and energy crashes, often associated with poor metabolic function and unstable blood sugar levels. Balanced cortisol levels and an in-sync circadian rhythm further support stable energy levels.
Metabolic flexibility is associated with a lower risk of insulin resistance, obesity, type 2 diabetes, and cardiovascular disease [4]. This protective effect is mainly due to the body’s improved ability to regulate blood sugar levels and reduce inflammation, outcomes that are influenced by the interplay between improved mitochondrial function, insulin sensitivity, and the anti-inflammatory effects of the antioxidant CoQ10 [4].
A flexible metabolism also plays a crucial role in reducing systemic inflammation, a major contributor to obesity and metabolic disorders. When fat cells become hypertrophied due to excess fat storage, they attract macrophages that release proinflammatory cytokines, such as IL-6 and TNF-α [5].
These cytokines promote insulin resistance and contribute to the development of atherosclerosis [5]. By encouraging fat burn and improving insulin sensitivity, metabolic flexibility helps to reduce the infiltration of these inflammatory cells, lowering systemic inflammation and decreasing the risk of type 2 diabetes, cardiovascular diseases, and certain cancers.
Metabolic flexibility is critical for brain function, as brain cells primarily rely on carbohydrates for energy [6, 7]. With enhanced insulin sensitivity, metabolic flexibility ensures that glucose is efficiently processed and delivered to the brain, supporting cognitive functions like memory, focus, and decision-making.
Moreover, a steady supply of carbs helps prevent mental fatigue and brain fog, which can occur when blood sugar levels are unstable [6]. By maintaining consistent energy levels, metabolic flexibility promotes mental clarity, alertness, and better cognitive performance.
During sleep, fat is your mitochondria’s preferred fuel source [8]. By effectively balancing your energy throughout the day, eating your carbs earlier, and not having a late dinner, your mitochondria will be able to transition from carb burn to fat burn overnight. Additionally, stable blood sugar levels, often a product of metabolic flexibility, help prevent overnight blood sugar crashes that can wake you up.
Metabolic flexibility is essential for longevity, as it supports health factors that contribute to a long, healthy life. Efficient mitochondrial function promotes sustained energy levels, preserves muscle mass, strengthens the immune system, helps you maintain a stable weight, and supports sharp cognitive abilities [1].
These factors work together to improve overall health and quality of life. By optimizing metabolic flexibility through nutrition, exercise, sleep, and stress management, you can enhance your mitochondrial health and, in turn, increase your chances of living longer.
Improving metabolic flexibility is a long-term lifestyle approach that involves more than temporary diet or exercise changes. It's about creating balance by supporting the body's natural rhythms and understanding your unique metabolism and how your daily choices can influence it.
By adjusting your habits to support healthy mitochondria, optimize insulin sensitivity, balance glycogen stores, increase muscle mass, manage cortisol levels, and align with your circadian rhythm, you can boost your metabolic flexibility, which pays dividends in energy, vitality, and longevity.
Remember, everyone's path to metabolic flexibility is unique, underscoring the importance of personalized nutrition plans and lifestyle adjustments based on real-time metabolic measurements.
The information Lumen provides is for educational and informational use only. You should seek the advice of your physician or other healthcare providers with any questions regarding your health.
[1] Goodpaster, B. H., & Sparks, L. M. (2017). Metabolic Flexibility in Health and Disease. Cell metabolism, 25(5), 1027–1036. https://doi.org/10.1016/j.cmet.2017.04.015
[2] Martins, F. O., & Conde, S. V. (2022). Impact of Diet Composition on Insulin Resistance. Nutrients, 14(18), 3716. https://doi.org/10.3390/nu14183716
[3] Murray, B., & Rosenbloom, C. (2018). Fundamentals of glycogen metabolism for coaches and athletes. Nutrition reviews, 76(4), 243–259. https://doi.org/10.1093/nutrit/nuy001
[4] Smith, R. L., Soeters, M. R., Wüst, R. C. I., & Houtkooper, R. H. (2018). Metabolic Flexibility as an Adaptation to Energy Resources and Requirements in Health and Disease. Endocrine reviews, 39(4), 489–517. https://doi.org/10.1210/er.2017-00211
[5] Song, D. K., & Kim, Y. W. (2023). Beneficial effects of intermittent fasting: a narrative review. Journal of Yeungnam medical science, 40(1), 4–11. https://doi.org/10.12701/jyms.2022.00010
[6] Mergenthaler, P., Lindauer, U., Dienel, G. A., & Meisel, A. (2013). Sugar for the brain: the role of glucose in physiological and pathological brain function. Trends in neurosciences, 36(10), 587–597. https://doi.org/10.1016/j.tins.2013.07.001
[7] Palmer, B. F., & Clegg, D. J. (2022). Metabolic Flexibility and Its Impact on Health Outcomes. Mayo Clinic proceedings, 97(4), 761–776. https://doi.org/10.1016/j.mayocp.2022.01.012
[8] Zhang, S., Tanaka, Y., Ishihara, A., Uchizawa, A., Park, I., Iwayama, K., Ogata, H., Yajima, K., Omi, N., Satoh, M., Yanagisawa, M., Sagayama, H., & Tokuyama, K. (2021). Metabolic flexibility during sleep. Scientific reports, 11(1), 17849. https://doi.org/10.1038/s41598-021-97301-8
Marine is a registered dietitian (RD) with extensive experience in clinical nutrition and a deep passion for well-being, health, and metabolism. With her background as a clinical dietitian and private practice owner, Marine has helped patients from diverse backgrounds improve their health through personalized nutrition. Currently, Marine serves as a customer success nutritionist at Lumen, where she provides expert nutrition support to clinics using Lumen’s technology to enhance their clients’ metabolic health. Marine is dedicated to empowering individuals to improve their relationship with food and achieve their health goals.