Metabolic Health in Perimenopause: Blood Sugar, Weight, and Insulin Resistance Explained
Metabolic changes in perimenopause affect weight, blood sugar, and energy. Learn the hormonal drivers and how to protect your metabolic health.
What Happens to Metabolism During Perimenopause
Many women in perimenopause report that their metabolism feels broken. They are eating and moving as they always have, yet weight is accumulating, particularly around the middle, in ways that resist any intervention. This is not a psychological perception. Measurable metabolic changes occur. Oestrogen plays a central role in insulin sensitivity, the efficiency with which cells respond to insulin and take up glucose. As oestrogen declines, insulin sensitivity reduces, and the body needs to produce more insulin to process the same amount of glucose. Elevated insulin promotes fat storage, particularly visceral fat. Resting metabolic rate also declines with muscle loss, since muscle is the body's primary calorie-burning tissue at rest.
Understanding Insulin Resistance in Perimenopause
Insulin resistance is a physiological state in which cells become less responsive to insulin's signal to absorb glucose. Blood glucose remains elevated longer after meals, the pancreas secretes more insulin to compensate, and chronically elevated insulin drives fat storage and inflammation. Left unaddressed, insulin resistance can progress to prediabetes and type 2 diabetes. Symptoms include persistent fatigue after carbohydrate-heavy meals, energy crashes mid-morning or mid-afternoon, difficulty losing weight despite controlled eating, and carbohydrate cravings. A fasting blood glucose and HbA1c test, routinely available through a GP, establishes whether blood sugar regulation is within a healthy range.
The Role of Visceral Fat
The shift in fat distribution during perimenopause, from hips and thighs to the abdominal area, is not merely cosmetic. Visceral fat, which accumulates around internal organs, produces inflammatory molecules that worsen insulin resistance, raise blood pressure, and promote systemic inflammation affecting joints, blood vessels, and the brain. Waist circumference is a more meaningful indicator of metabolic risk than body mass index: above 80 centimetres in women is associated with increased cardiovascular and metabolic risk. The hormonal shift of perimenopause actively promotes visceral fat accumulation, making it harder to manage through caloric restriction alone. Resistance training, sleep optimisation, and stress management are more effective than calorie restriction at shifting this pattern.
Dietary Strategies for Metabolic Health
What and when you eat significantly affects blood sugar regulation. Reducing rapidly absorbed carbohydrates, including refined grains, sugar, and ultra-processed foods, reduces the glucose and insulin spikes that drive fat storage. Choosing slower-digesting options such as whole grains, legumes, vegetables, and whole fruit helps maintain stable blood sugar. Protein has a minimal effect on blood glucose, supports muscle maintenance, promotes satiety, and requires more energy to digest. Including a meaningful protein source at every meal stabilises blood sugar across the day. Healthy fats from nuts, seeds, avocado, and olive oil support satiety. Eating the majority of calories earlier in the day, when insulin sensitivity is higher, aligns food intake with the body's metabolic rhythms.
Exercise and Its Metabolic Effects
Exercise is the most powerful tool available for improving insulin sensitivity. A single session of resistance training or brisk walking improves the ability of muscle cells to take up glucose for 24 to 48 hours after the session. This is why exercise frequency matters: doing something active most days keeps insulin sensitivity continually elevated. Resistance training builds muscle, and each additional unit of muscle mass increases resting glucose disposal and basal metabolic rate. High-intensity interval training has a particularly strong and efficient effect on insulin sensitivity. Zone 2 aerobic training improves mitochondrial function and fat metabolism over time. A programme combining both forms alongside resistance work provides comprehensive metabolic support.
Sleep, Stress, and Blood Sugar
The connection between sleep, stress, and blood sugar regulation is more direct than most people realise. A single night of poor sleep reduces insulin sensitivity the following day by a measurable amount comparable to gaining several kilograms of body fat. Chronic sleep disruption from night sweats has a sustained negative effect on metabolic health independent of diet and exercise. Cortisol, the primary stress hormone, directly raises blood glucose by triggering glycogen release from the liver. Chronic psychological stress therefore worsens blood sugar regulation and promotes visceral fat accumulation. Addressing sleep disruption and managing stress through exercise, mindfulness, and social connection are central to metabolic health, not optional extras.
Monitoring Metabolic Health and When to Seek Help
Perimenopause is an important time to be proactive about metabolic health. Annual fasting blood glucose, HbA1c, a lipid panel, blood pressure, and waist circumference measurement give a meaningful picture of metabolic trajectory. If results are trending in an unhealthy direction, early intervention with lifestyle changes and if appropriate medication is far more effective than waiting until diabetes has developed. HRT has been shown to improve insulin sensitivity and reduce the risk of type 2 diabetes in postmenopausal women. Tracking energy, food responses, sleep, and exercise in an app like PeriPlan helps you understand what is helping and provides a clear record for healthcare conversations. Small, consistent changes during perimenopause compound into significant long-term health outcomes.
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