Metabolism: The Many Factors That Contribute To It
Metabolism, Hormones, Blood Sugar and More!
What are some buzz words that come to mind when you think of metabolism? Do thoughts of less than pleasant diets and exercise regimes come to mind? As a matter of fact, science shows that metabolism is controlled by a variety of factors, including lifestyle, diet and hormones. Age also plays a role in metabolism as our need for a high caloric diet decreases each decade we become older. Additionally, our basal metabolic rate decreases, which is influenced by thyroid hormone. Physical activity effects the amount of calories utilized through thermogenesis, and may decrease based on factors outside of our control, such as injury, chronic pain and age related disability. In addition to thyroid hormone; estrogen, progesterone and cortisol are all hormones that effect the rate of our metabolism.
Each of the hormones mentioned above impacts our metabolism in an unique way. Thyroid hormone (in the forms of T4 and T3), is known as the “master hormone” and is produced by a tiny gland that sits below the larynx. It is the hormone most directly responsible for metabolism, or the rate at with food is broken down into energy. Numerous studies have indicated that there is a high correlation with BMI and impaired thyroid function. Many obese individuals have been found to have subclinical thyroid dysfunction, and improve with proper treatment (4). Hormonal imbalances leading to estrogen dominance may lead to increased abdominal, or visceral obesity. Finally, cortisol has been shown to contribute to abdominal obesity, increase blood sugar levels and impair the function of the thyroid gland, all of which have serious long term health consequences (1).
In addition to ensuring enough physical activity and optimal hormonal health, glycemic control is an important factors to address for healthy metabolism as we age. Blood glucose pays an important role in weight control as glucose can be converted to triglycerides and stored as fat when not used as energy or stored as glycogen. If insulin levels elevate over time, an enzyme that helps break down body fat to be burned is suppressed called hormone sensitive lipase.
The glycemic index is a measurement of the extent at which various foods escalate blood glucose after a meal. High fiber, low index foods have been associated with a healthy weight and feelings of satiety. Some low glycemic, high fiber foods include pearled barley, other whole grains, green leafy vegetables and legumes. The Linus Pauling Institute provides a comprehensive guide to understanding the glycemic index: https://lpi.oregonstate.edu/mic/food-beverages/glycemic-index-glycemic-load (2).
Consuming a nutrient rich diet with a variety of fresh fruits and vegetables is essential to a healthy metabolism and overall longevity. Healthy fats such as olive oil, avocado oil and omega 3 fatty acids should be chosen over trans fats or hydrogenated oils. Reducing intake of sugar and avoiding processed carbohydrates such as white bread, rice and pasta and increasing high quality, lean proteins help maintain healthy blood sugar and insulin levels. Finally, choosing meals with color variety, particularly of vegetables and fruits, has been shown to not only increase the nutrient content and variety of meals, but also lead to better taste! (3). At Wholehearted Naturopathic, we offer a variety of services to help you meet your goals that relate to metabolism and hormonal concerns. Please visit our home page or contact page to find out more about our services, ask us a question or book online with us.
Sources:
Abraham, S., Rubino, D., Sinaii, N., Ramsey, S., & Nieman, L. K. (2013). Cortisol, obesity, and the metabolic syndrome: A cross‐sectional study of obese subjects and review of the literature. Obesity, 21(1), E105-E117.
“Glycemic Index and Glycemic Load.” Abstracted from: https://lpi.oregonstate.edu/mic/food-beverages/glycemic-index-glycemic-load
König LM, Renner B. Boosting healthy food choices by meal colour variety: results from two experiments and a just-in-time Ecology Momentary Intervention. BMC Public Health. 2019;19(1):975. doi:10.1186/s12889-019-7306-z
Mullur, R., Liu, Y. Y., & Brent, G. A. (2014). Thyroid hormone regulation of metabolism. Physiological reviews, 94(2), 355-382.
