Decoding Your Metabolism: Why Weight loss is More Than Just Calories

It is time to shift the narrative away from the idea that weight is solely a reflection of willpower. If you’ve been struggling with your weight, I want you to take a deep breath and let the guilt go. Sometimes, you can do "everything right" and still not see the scale move because of things you can’t see happening under the surface. Science has made it clear that changes in body weight, or difficulty reducing weight, is often the result of complex physiological factors that are beyond your conscious control.

To understand weight management from an evidence-based, naturopathic perspective, we have to look beyond the "energy in vs. energy out" model. The rate at which we burn that energy and the signals that tell us to store it are governed by complex biological systems.

There are many factors influencing metabolism and weight, and as a naturopath, I understand that each person has their own individual biochemical blueprint that determines how they process nutrients, manage stress, and store energy.

Factors Affecting Weight Loss

Insulin Sensitivity

Insulin is your primary fat-storage hormone. When cells become resistant to insulin, the body must produce more of it to manage blood sugar. High circulating insulin levels inhibits lipolysis (the breakdown of fat cells). Research shows that high baseline insulin sensitivity is associated with better retention of lean muscle mass during weight loss, which is crucial for maintaining a healthy metabolic rate. Obesity and insulin resistance are bi-directionally linked; obesity generates resistance, while resistance promotes further adipose (fat) storage.

The Gut Microbiome

Your gut bacteria play a significant role in the amount of calories your body absorbs from the food you eat. Research has found the gut microbiome can predict an individual's success on a calorie-restricted diet with 80% accuracy.

Sleep Architecture & Circadian Rhythms

Sleep is a metabolic necessity. When sleep is disrupted, the hormones regulating hunger (ghrelin) and satiety (leptin) become dysregulated, and glucose metabolism is altered. There is evidence that sleeping 5 hours or fewer per night is associated with an increased risk of obesity and higher BMI.

Chronic Stress

Cortisol, a hormone produced during the stress response, is a major driver of abdominal (visceral) fat. Unlike subcutaneous fat (under the skin), visceral fat is metabolically active and inflammatory. Elevated long-term cortisol levels are correlated with higher BMI and waist circumference.

Environmental Obesogens

Emerging research identifies specific environmental toxins, known as obesogens, that disrupt the endocrine system and alter fat cells. Many chemicals, including BPA (plastics), phthalates, and certain pesticides, have been identified as having significant evidence of obesogenic effects. These chemicals can interfere with the number and size of fat cells altering the basal metabolic rate (BMR) by mimicking or blocking natural hormones.

From a clinical perspective, managing weight is essential for health because it reduces systemic inflammation and hormonal disruptions that increase the risk of chronic disease. But let's balance this with some self compassion <3

How can I help...

Jodie works with her patients to investigate and treat the underlying cause of weight gain. Treatment with evidence-informed strategies are individual to each patient, and may include herbal medicine, nutritional strategies and/or supplementation, and lifestyle strategies.

Jodie can collaborate with your GP to ensure nutritional recommendations safely complement any existing medications or medical treatments for weight loss.

Find out more about Jodie here or book a Nutrition Strategy Session here

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Micić, D., Polovina, S., Micić, D., & Macut, D. (2021). Enocrine Disrupting Chemicals and Obesity: The Evolving Story of Obesogens. Acta endocrinologica (Bucharest, Romania : 2005), 17(4), 503–508. https://doi.org/10.4183/aeb.2021.503