Feast and fast = The cycle of life Have you ever questioned the benefit of eating three meals a day – or three meals and two snacks? Your circadian rhythms naturally govern your behaviours and hormones (such as growth hormones, cortisol, or insulin). Meal timing impacts the circadian rhythms through the body’s peripheral clocks. Now is a great time to ask when you should eat beyond what you should eat.
Fasting is the voluntary abstinence from solid food and stimulants for a limited time and the ability to meet energy requirements mostly or exclusively from the body’s energy reserves without endangering health. You are already fasting every night. Fasting or Time Restricted Eating (TRE) is not a diet but an eating pattern. This approach involves changing WHEN you eat instead of WHAT you eat.
The Purpose of Fasting
1. Waistline and blood sugar regulation:
Switching from food to stored energy for energy production . Your digestive system requires a minimum of 5 hours to process a meal. Your body first runs on dietary glucose to produce energy. Over the next 10 to 15 hours, it progressively processes glucose stored in the liver (glycogen) followed by fatty acids, to sustain this energy production. When you eat around the clock, this adaptive mechanism, called metabolic flexibility, is lost over time.
Fasting promotes healthy insulin regulation and weight loss by maintaining metabolic flexibility.
2. Digestive rest and microbiome relief:
The digestive rest that occurs when you practise TRE or Intermittent Fasting will promote microbial diversity in your gut. Intermittent fasting can also reduce inflammation, improving your digestive health.
3. Mental health and relationship to food:
Fasting is a new physical, mental and spiritual experience. For most of us, our biggest issue with fasting is mind over matter. However, your thought process can change over a few weeks. A recent meta-analysis also shows the benefits of fasting for stress, anxiety and depressive symptoms.
4. Ageing and oxidative stress
Many of the body’s usual processes produce reactive chemical molecules called free radicals. These molecules generate oxidative stress when the body’s antioxidant defence mechanisms are overwhelmed with increased environmental toxicity, poor digestion or blood sugar dysregulation. Oxidative stress leads to tissue and cellular damage. If not controlled, oxidative stress may induce both chronic and degenerative diseases. During fasting, your body responds by significantly increasing its antioxidant defence mechanisms, preserving cellular function and promoting longevity
Fasts can range from twelve hours to ten days or more. You can fast once a week, once a month or once a year. Shorter fasts are generally done more frequently. Longer fasts are typically 24-36 hours. Fasting has no standard duration, and no single schedule will work for everybody all the time. Prolonged fasting requires supervision.
Fasting Window Length
Who is it for?
12 hour fasting window
Overnight fasting to improve blood sugar and sleep
Metabolic health benefits are slower to show
16 hour fasting window
Fits into most lifestyles. Easy to manage while providing noticeable benefits
Can be a long fasting time if you are new to fasting
For beginners of TRE
20 fasting window
Suits a busy lifestyle with a condensed eating time
Requires a balanced diet
If you have experience in TRE
Intermittent fasting relates to any fasting pattern over 24 hours and involves cycling between eating and fasting periods.
Who is it for?
OMAD or 24 hour fast
One meal a day
Food preparation is easy to fit into a busy schedule
Can start to look like chronic calorie restriction. May lower your resting metabolic rate over time8
Works best if you have tried some TRE first. Recommended once or twice weekly
2 days = 0-25% of normal calorie intake 5 days = eat "normally"
No long period of food abstinence
Counting calories over 2 days
For those daunted by the idea of going without food for long periods
Feast and fast – can you eat what you want?
There’s a little myth that says you can eat whatever you want during TRE/ IF. This is simply not true. As you reduce your eating window, you need to put as many nutrients on your plate as possible from whole, unprocessed foods. This starts with eating plant foods in abundance. Processed foods are empty calories and come with blood sugar spikes and crashes which can leave you feeling tired, foggy and hungrier during your fasting window. You will be far less likely to stick with fasting when you feel this way. And the effects of these foods that are felt in the longer term (sleep disturbances, bloating, constipation, and exhaustion) won’t exactly make your next fasting window easy, either.
To make fasting easy and enjoyable:
• Apply the fundamentals of a healthy diet.
• Plan your meals ahead of time.
• Watch what you drink. Replace soft drinks and caffeinated drinks with water and herbal tea. Keep your hydration optimum. Mixed signals for hunger and thirst can happen because they’re interpreted in the same part of your brain.
The Mediterranean Diet provides ample vitamins, minerals and healthy fats to stabilise your blood sugar levels, help you feel satiated and prevent symptoms like dizziness. Think about avocado, green leafy vegetables, wild fish, nuts, seeds and extra virgin olive oil. Aim to fill half of your plate with non-starchy vegetables.
Stock nutritious meals in your fridge at the beginning of the week and clear your cupboards of convenient, calorie-dense/nutrient-poor foods. Planning can make all the difference in your fasting results.
Choose the schedule that suits your lifestyle and the eating window you feel more at ease with.
A sample day on a 16:8 Fast
Example for a 10am – 6pm eating window:
1. From waking up to your eating time, start with lemon in water, indulge in dandelion root tea or any other herbal tea and a moderate amount of black coffee.
2. Split your eating window into two or three meals –
10am: Make the first meal the largest of the day. E.g. a “Buddha Bowl” composed of lentils, kale, spinach & poached eggs sprinkled with pumpkin seeds
2pm: Second meal - if you choose to have it – is light. E.g. a salad based on greens, tomatoes, olives, avocado, quinoa & seeds
6pm: Last meal is light. E.g. a small portion of salmon with roasted vegetables
3. After your last meal, indulge in water, and herbal tea.
What breaks your fast?
When practicing TRE, focus solely on non-caloric beverages during your fasting window. Water will be your best friend and an essential component of your fasting window. Keep in mind you will need additional water to compensate for food-driven hydration. You can add some lemon juice to your water for a fresh taste and some additional electrolytes. Coffee used in moderation may benefit your fast. Ensure you drink black coffee without sugar or milk and have a glass of water with any coffee. Limit your consumption to one or two cups a day.
What supplements break your fast?
A fast is broken by anything that stimulates an insulin response. Protein powder and multi vitamin gummies will surely break your fast, as well as prebiotic fibres. When taking supplements, examine the excipient list - maltodextrin and pectin contain sugar and calories that could break your fast. Sugar alcohols such as myo-inositol can also affect your blood sugar levels. Stevia or monk fruit do not, but can trigger your hunger signals. Electrolytes are beneficial during your fasting window as long as the supplement does not contain sweeteners or other calories. Some supplements won’t break your fast but are better taken with food. Fat soluble vitamins and omega-3 fatty acids are best absorbed when the digestive system is stimulated. Some people become nauseous when they take zinc on an empty stomach; and chromium may cause your blood glucose to go too low during your fasting window. It is always best to contact your practitioner for specific advice on the impact of supplements on fasting and vice versa.
A tip I give all my clients for medication that needs to be taken in the morning or before bed - have a spoonful of full fat yoghurt or cream - the fat will signal a lower insulin response than a carbohydrate snack.
Body Signs and Symptoms to be aware of when you start fasting
You may experience light headedness when you stretch out your fasting time.
First, check you are not dehydrated. As mentioned, hydration comes from food, and you may have missed regular water during your fasting window. If the light headedness happens because your body has lost its metabolic flexibility, then consider returning to a 12-hour fasting window, assess the quality of your diet by avoiding simple sugars and increase your fasting window progressively.
If you feel nauseous or sluggish, ensure you have regular bowel movements prior to opening your fasting window. When you are constipated, your body holds onto toxicity. It makes the fasting window more difficult to tolerate
If you feel fatigued, don’t stop moving. Scale back on intensity if needed, get up and move. Movement will increase your energy demands and force your body to burn stored fat at a higher rate to refuel your system quicker.
Always listen to your body. If you feel unwell, break your fast. There is always tomorrow to try again.
1. Eat well for fasting = you will get better results and comfort during your fast. Think about a traditional Mediterranean diet.
2. If you don’t feel good with one fasting schedule, look for support and try another one.
3. No one schedule fits anyone all the time.
4. 16:8 is what I recommend to my clients to begin with, to help regulate hormones and clear their skin.
I hope this information has helped any confusion surrounding Fasting and it benefits and drawbacks. If you would like more guidance on how to fast or if it is right for you, book in for an appointment here.
If you would like more information on my program that helps women regulate their cycles, gain clear, glowing skin and feel vibrant in their body, you can read more by clicking the link below.