Taking care of women in midlife – what I hear from my patients so often is a sense of genuine confusion: they are eating and exercising the same as they always have, yet they are suddenly gaining weight. What’s happening here?  As you move into perimenopause, your estrogen levels begin to fall, triggering a significant and sometimes frustrating internal shift.

Now, it is important to understand that this drop in estrogen doesn’t happen in a vacuum; it actually leads to higher levels of cortisol and an increased sensitivity to that stress hormone. The combination of falling estrogen and rising cortisol sensitivity is what drives an increase in insulin resistance and elevations in cholesterol levels. This shift may also explain why so many women experience a change in their body composition. Research shows that during the two years before and after your last period there is a doubling in fat acquisition accompanied by a simultaneous decrease in muscle mass. This isn’t a failure of willpower; it is a physiological response to the lack of estrogen and the higher cortisol environment your body is now navigating.

To improve your resilience to change during this transition, I recommend focusing on two foundational areas:

  • Fasting for metabolic resilience
  • Meditation and breathwork for emotional/neurological resilience

 

Strategic Fasting and Timing

Fasting is perhaps the most significant intervention for influencing your metabolism and longevity over time. It helps your body initiate a “metabolic switch” from glucose burning to fat burning (ketosis).

  • The 12-Hour Foundation: For general longevity, I recommend at least a 12-hour overnight fast between dinner and breakfast.
  • Weight Loss Windows: If weight loss is the goal, you can extend that window to 14 or 16 hours, though this is meant to be a tool for a season rather than a lifelong rule.
  • The 5-Day Fasting Mimicking Diet: Periodic longer fasts, like the five-day Prolon program, can trigger autophagy, a “cellular spring cleaning” where your body breaks down old “zombie cells” for energy. I typically suggest doing this twice a year, or once a month for three months if you are working on specific goals like lowering cholesterol, losing weight, improving glucose levels.
  • Menstrual Cycle Timing: If you are still getting periods, focus your more intense fasting on the first two-three weeks of your cycle when you are more resilient. Avoid long fasts the week before your period, as your body is more sensitive to cortisol then, and high cortisol can actually signal your body to retain fat.

I go more in depth into these topics in my previous blogs: Intermittent Fasting – Is it Right For You?  and Prolon Fasting Mimicking Diet with Bronwyn Fitz.  My two favorite resources for this topic are Valter Longo, longevity and fasting researcher, and Mindy Pelz, a nutritionist and author.

 

Managing the Cortisol Connection

The hormonal shifts in midlife are very stressful on the body. We cannot talk about metabolism without talking about stress. Chronically elevated cortisol makes it very difficult to lose weight. This is why I am passionate about incorporating breathwork and meditation, because they exercise the parasympathetic nervous system- the “rest and digest” mode. They have been shown to reduce stress, depression, anxiety, and improve overall wellbeing.

There are many styles of meditation (breath focused, mantra, loving kindness, sitting, walking, etc).  There are also many forms of breathwork (4-7-8 breathing, box breathing, cyclic sighing).

Try a cyclic sigh right now:

  • inhale deeply through your nose over 2 seconds
  • take one extra “sip” of air to really expand your lungs to the max
  • exhale slowly through your mouth over 6-8 seconds

Even one to five minutes a day of these practices can improve your stress response. Best of all, these practices are free and readily accessible to you at any place and time of the day.

So where does this leave us? The bottom line is that your 40s and 50s require a different approach than your 20s. By using these tools to build metabolic and neurologic flexibility, you aren’t just fighting weight gain; you are building resilience for a new and amazing phase of life.

Dr. Bronwyn Fitz is double board-certified in Obstetrics and Gynecology and Integrative Medicine. If you would like to learn more about her practice or make an appointment, please visit her website and click on the “Get started” tab to set up a free 15-minute discovery call.