Metabolic Health 2/2: The Factors That Weaken Your Metabolism

This article is the second part of our two-part series on metabolic health. In the first part, we explored what metabolic health actually is, why it matters, and how it can begin to deteriorate well before any diagnosis. Here, we look at the factors that can weaken the metabolic foundation, and at the levers that genuinely move the needle.

Metabolic health is the result of ongoing interactions between physical activity, muscle mass, sleep, stress, nutrition, hormones, inflammation, and body composition. The good news: most of these factors are modifiable, and the most effective levers are not necessarily the most complex ones.

1. Reduced storage capacity: less muscle, less metabolic margin

Muscle is often perceived through an aesthetic or athletic lens. Yet physiologically, it is one of the most important organs in metabolism.

After a meal, a large portion of glucose is directed toward muscle tissue, where it will be used as fuel or stored as glycogen. The greater and more functional the muscle mass, the higher this storage capacity. Conversely, when muscle mass decreases, the body has less tissue capable of efficiently capturing and storing glucose after meals. This progressive reduction in storage capacity can contribute to poorer insulin sensitivity.

What accelerates muscle loss:

• Sedentary behavior

• Lack of strength training

• Insufficient protein intake

• Prolonged caloric restriction

• Aging

• Perimenopause and menopause

What you can implement

• 2 to 3 strength training sessions per week, with regular progression in load or difficulty.

• Include a source of protein at every meal to support muscle mass and recovery.

• Avoid aggressive and repeated caloric restrictions.

• Monitor body composition, not just weight.

2. Progressive accumulation of visceral fat

Not all body fat behaves the same way. Visceral fat, which accumulates around the abdominal organs, is particularly important from a metabolic standpoint. More active than subcutaneous fat, it produces various inflammatory molecules and influences several mechanisms involved in the regulation of glucose, lipids, and energy.

When it increases, it is associated with:

• Poorer insulin sensitivity

• More low-grade chronic inflammation

• Higher cardiovascular risk

• An increased risk of hepatic steatosis

• An increased risk of type 2 diabetes

This is one of the reasons why two people with the same weight can have very different metabolic profiles.

Practical reference points

• Waist circumference ≥ 80 cm in women and ≥ 94 cm in men: thresholds used by the International Diabetes Federation as markers of increased cardiometabolic risk.

• DEXA Scan provides a precise assessment of fat mass distribution and visceral fat.

What can help

• Preserve or build muscle mass.

• Maintain a high level of daily movement.

• Build a diet rich in protein, fiber, and minimally processed foods.

• Optimize sleep.

• Reduce chronic stress load.

The good news is that visceral fat generally responds well to lifestyle changes and is often one of the first fat compartments to decrease when metabolic health improves.

3. Movement: an essential biological signal

Physical activity is often associated with caloric expenditure. Its metabolic role, however, goes well beyond that. Movement acts as a true biological signal that influences the way cells use energy.

When muscles contract, they increase their glucose consumption and improve their capacity to capture and use it. Over the long term, physical activity contributes to improving insulin sensitivity, preserving muscle mass, limiting the accumulation of visceral fat, and supporting cardiovascular health.

A frequently overlooked point: it is possible to train several times a week while remaining very sedentary the rest of the time. Yet the total amount of daily movement matters enormously. Studies show that regular short breaks from prolonged sitting can improve glycemic and insulin responses after meals.

What you can implement

• Walk for 10 to 15 minutes after meals, particularly those highest in carbohydrates.

• Increase your daily movement: take the stairs, use active transportation, take phone calls while walking, take regular breaks when working seated.

• Combine resistance training and cardiovascular activity, according to your abilities and recovery capacity.

4. Sleep and recovery

Metabolism is not built solely during periods of activity. It also depends on the body's ability to recover.

Sleep directly influences insulin sensitivity, appetite regulation, glucose management, inflammation, stress hormones, and muscle recovery. When sleep becomes insufficient, fragmented, or irregular, these systems progressively begin to lose efficiency.

Studies show that chronic sleep restriction is associated with impaired insulin sensitivity, increased appetite, and a higher risk of metabolic dysfunction. The mechanisms involve in particular cortisol, the autonomic nervous system, inflammation, and the hormones involved in hunger and satiety.

What you can implement

• Aim for 7 to 9 hours of sleep per night.

• Maintain relatively consistent sleep and wake times.

• Get exposure to natural light in the morning.

• Limit screen use before bedtime.

• Avoid very large meals just before sleeping.

Sleep is not simply a rest period. It is a metabolic function in its own right.

5. Chronic stress

Stress is part of human physiology. In the short term, it enables the rapid mobilization of energy. The problem arises when this mobilization becomes chronic and recovery periods become insufficient.

In this context, several systems involved in metabolic health can be affected: glucose regulation, appetite, sleep, inflammation, recovery, and body composition. In some people, this can manifest as unstable energy levels, more cravings, slower recovery, increased abdominal fat storage, and persistent fatigue.

The problem is not stress itself. The problem is the absence of recovery.

What you can implement

• Integrate genuine recovery moments into the week.

• Practice heart coherence breathing, slow breathing, or meditation regularly.

• Walk more, particularly outdoors.

The body is designed to tolerate periods of stress. It is far less equipped to function durably in a state of permanent mobilization.

6. Nutrition

When discussing metabolic health, debates often focus on a particular nutrient: carbohydrates, protein, or fat. Yet the scientific literature suggests that the overall quality of the dietary pattern is generally more important than any single isolated nutrient.

The characteristics most frequently associated with better metabolic health are:

• Sufficient protein intake

• High consumption of fiber-rich plant foods

• Low consumption of ultra-processed foods

• High nutritional density

• An energy intake consistent with the individual's needs

Beyond food quality, meal structure also appears to be important. Meals built around protein, fiber, and minimally processed foods generally promote better satiety and a more favorable glycemic response.

What you can implement

• Include a source of protein at every meal.

• Consume more fiber-rich plant foods.

• Prioritize minimally processed foods most of the time.

• Reduce constant snacking when it is present.

• Start meals with vegetables and protein before the foods highest in carbohydrates.

The often underestimated role of micronutrients

Certain micronutrients directly participate in the mechanisms involved in glucose regulation and insulin sensitivity. The most studied include magnesium, vitamin D, zinc, and omega-3 fatty acids. When an insufficiency or deficiency is present, it can limit the effectiveness of the other interventions put in place. This is also why measuring is often more relevant than assuming.

The specific case of women over 40

Perimenopause and menopause represent a major metabolic transition period. The gradual decline in estrogen influences in particular fat mass distribution, muscle mass, recovery, insulin sensitivity, and cardiovascular health.

Many women then observe changes in their body composition despite relatively similar habits. These changes do not mean that metabolic deterioration is inevitable. They simply make certain levers even more important:

• Preserve muscle mass

• Maintain sufficient protein intake

• Continue regular strength training

• Limit sedentary behavior

Perimenopause is probably one of the most important metabolic prevention windows in a woman's life.

Why the same strategies do not produce the same results

Two people can apply exactly the same recommendations and achieve very different results. Why? Because the starting point is not the same. Some people already have low muscle mass. Others have higher chronic inflammation, poor sleep quality, visceral fat accumulation, or certain nutritional deficiencies. These factors directly influence how the body responds to nutritional and lifestyle interventions.

This is also why measuring is often more useful than guessing. Understanding your baseline allows you to identify the most relevant levers, rather than applying the same recommendations to everyone. This is precisely where biomarkers change the picture.

At Lucis, we analyze more than 110 biomarkers, including fasting insulin, HOMA-IR, HbA1c, triglycerides, HDL, hsCRP, vitamin D, magnesium, omega-3s, and several key metabolic markers. The goal: to understand what is truly influencing your energy, body composition, inflammation, recovery, and long-term health.

Key takeaways

Metabolic health does not depend on a miracle food, a supplement, or an isolated strategy. It is built progressively through the accumulation of favorable biological signals: more muscle mass, more movement, quality sleep, better recovery, an appropriate diet, and an environment compatible with the body's needs.

The good news is that these factors remain largely modifiable. And in many cases, improvements appear well before weight changes: more stable energy, better recovery, better-regulated hunger, more favorable body composition, or biomarkers moving in the right direction.

Because when it comes to metabolic health, the goal is not only to live longer. It is also to preserve, for as long as possible, the energy, mobility, and adaptive capacity that characterize a healthy body.

Listen to the podcast

If you want to go further, listen to our latest episode in which Anaïs Gautron welcomes David D'Hont, an expert in micronutrition, to explore the mechanisms behind insulin sensitivity, metabolic flexibility, and metabolic health as a whole.

Disclaimer

The information contained in this article is provided for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before modifying your lifestyle habits or medical follow-up.

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