Is Intermittent Fasting Destroying Your Hormones?

At Synergised, we’re passionate advocates of intermittent fasting - when it’s done correctly and tailored to individual needs. Without considering key factors like bio-individuality, intermittent fasting can do more harm than good and may even pose risks to certain health conditions.

One critical aspect is gender, as women can face unique challenges with intermittent fasting. Body type is another essential consideration. For example, intermittent fasting often aligns well with the Kapha body type, while those with a Vata constitution should approach it more cautiously. If you’re unsure about your Dosha or body type, we encourage you to explore our guide here to help you identify it.

Ignoring these nuances and the principles of bio-individuality can have significant consequences, including the potential to disrupt hormonal balance. That’s why we emphasise a personalised approach - our health and well-being depend on it.

What Is Intermittent Fasting?

Intermittent fasting involves alternating periods of eating with periods of fasting. A minimum fasting window is typically 12 hours, though many choose longer durations. For most people, we recommend a 12-hour overnight fast, such as finishing dinner by 7 pm and having breakfast at 7 am. This allows your body ample time for digestion and gut recovery, offering benefits like improved metabolic health, reduced inflammation, and enhanced cellular repair.

However, it is essential to consider your unique circumstances, including gender, body type, and any pre-existing health conditions, to determine if intermittent fasting is right for you. For instance, people with hypothyroidism or adrenal fatigue should approach fasting cautiously, as it may exacerbate these conditions.

Intermittent Fasting and Female Hormones

For women, intermittent fasting can have complex implications due to hormonal sensitivity. Women’s bodies are biologically designed to support reproduction, so extended fasting periods may signal to the body that food is scarce and it is not an ideal time for reproduction. This can disrupt levels of essential hormones like estrogen and progesterone.

Oestrogen plays a critical role beyond reproduction, influencing metabolism, weight regulation (especially around the midsection), mood stability, cognitive function, and energy levels. When estrogen becomes imbalanced, it may lead to:

• Weight gain
• Poor cardiovascular health
• Reduced muscle mass and metabolism
• Impaired cognitive function
• Blood sugar dysregulation
• Fatigue and even infertility

Hormones work synergistically, meaning that an imbalance in one can disrupt others. A dip in estrogen may lead to imbalances in cortisol (the stress hormone) and thyroid hormones, potentially causing anxiety, insomnia, sugar cravings, brain fog, irregular menstrual cycles, and more.

Avoid These Intermittent Fasting Mistakes

1. The 16/8 Method
   The 16/8 method, where you fast for 16 hours and eat within an 8-hour window, has gained popularity. While this may suit individuals with strong digestion (e.g., Pitta body types in Ayurvedic terms), it can strain the digestive system for others, particularly those who struggle to consume sufficient calories and nutrients within such a restricted timeframe.

If you’re following this type of fasting, you’re likely only having two meals per day, which isn’t ideal. Larger meal portions can be very heavy on the digestive system, making it harder to process efficiently. Secondly, it’s challenging to meet all your nutrient requirements with just two meals a day. For these reasons, we recommend having three meals spread across your eating window for better digestion and overall nutrient intake.

1. Skipping Breakfast
   Skipping breakfast is a common approach for longer fasting methods like 16/8 or 18/6. While it might yield short-term weight loss, it can backfire in the long term by lowering your metabolism. When you skip breakfast, your body perceives this as stress, triggering a cortisol spike. Elevated cortisol signals the body to conserve energy, lowering thyroid hormone levels and slowing metabolism.

Additionally, breakfast is critical for stabilising blood sugar levels and supporting cognitive and physical performance throughout the day. Scientific studies even show that skipping dinner rather than breakfast is metabolically more efficient, as our circadian rhythms favour stronger metabolism and blood sugar control in the morning.

How to Use Intermittent Fasting Safely

1. Personalise Your Approach

Intermittent fasting should be tailored to your unique bio-individuality. Factors like gender, dosha (body type in Ayurveda), and any pre-existing health conditions must be taken into account. For example:

• Vata body types (slender and prone to stress) should avoid prolonged fasting as it can exacerbate imbalances.
• Kapha body types (sturdy and slower metabolism) may benefit the most from intermittent fasting.

At-home functional medicine tests can help determine how fasting may affect your hormones, thyroid, and overall metabolism.

2. Avoid Skipping Breakfast

Instead of skipping breakfast, consider finishing your evening meal earlier. Breaking your fast with a nutrient-dense breakfast supports stable blood sugar levels and promotes overall metabolic health. Listen to our episode “How Skipping Breakfast Affects Female Hormones” here.

3. Monitor Stress Levels

Fasting is a stressor on the body, and when combined with other stress-inducing activities like high-intensity interval training (HIIT), it can lead to elevated cortisol levels. Women, in particular, should avoid intense workouts on days of prolonged fasting. Opt for lighter activities such as yoga or walking instead.

4. Implement Strategic Extended Fasts

While we caution against prolonged fasting daily, longer fasting periods can be beneficial when done occasionally. At Synergised, we recommend our 21-Day Reset programme for those new to functional medicine detoxes. For ongoing maintenance, the 7-Day Reset every season is ideal to help boost mitochondrial health, enhance cellular clean-up, and support overall wellness.

Final Thoughts

Intermittent fasting is a powerful tool for improving health and longevity, but it must be practised with care. Women, in particular, should pay close attention to how fasting affects their hormones and metabolism. Personalising your fasting routine to suit your body type, health status, and lifestyle is key to reaping its benefits without causing harm.

At Synergised, our integrative approach combines science-backed strategies with ancient wisdom to support your journey to optimal health. 

Your health is unique. Let’s make intermittent fasting work for your body, not against it.