We know that WHAT we eat matters. But does WHEN we eat make a difference?
Fasting is fast overtaking dieting as a health trend. But is fasting really a new idea or is it just calorie restriction in disguise? Is it as healthy as the pundits claim or could you be doing yourself harm by not eating for extended periods?
ABC radio host Cathy Border asks for the facts on fasting.
To listen to our conversation click here.
Below are some key takeaways.
What exactly does fasting entail (not in a religious context but a health context)? Is it just dieting by another name?
Fasting is not the same as dieting.
Fasting means not eating anything or eating no more than 600 Calories per day for one or two days per week or even just one or two days per month.
It’s important to maintain fluid intake. However, when fasting, this only includes water, green or black tea or black coffee. Adding sugar or milk to your tea or coffee will break the fast.
The second way that people fast is what’s more accurately called Time Restricted Feeding (TRF).
In my experience this is the simplest, easiest and most effective way to start shedding excess body fat. All you need to do is to leave as long a gap as possible between dinner and breakfast – at least 12 hours. This allows your body to switch from burning carbohydrates for fuel to burning fat for fuel. And the switch from carb to fat burning happens after 12 hours of not eating. So the longer you delay breakfast, the more fat you will burn. The optimal benefits seem to come from a 16 hour gap but anything beyond 12 hours is beneficial and you can slowly work your way to 16 hours.
As mentioned above, during your 12 to 16 hour break from eating, you can only have water, black or green tea, or black coffee.
Studies have shown that even if you eat the same number of calories in a day, if you restrict your eating to a smaller feeding window like 8 hours, you will shed much more body fat than if you eat the same food – with the same calories – over the course of 12 or more hours.
What are the health benefits of fasting?
- Fasting and TRF allow your body to stop producing insulin during the hours that you’re not eating. This is the number one way to prevent type 2 diabetes, heart disease and a range of other chronic illnesses. Insulin is a hormone that promotes fat storage. Therefore turning off insulin allows your body to release stored fat. This is why people shed body fat even if they’re eating the same number of calories.
- Fasting improves bowel function because your bowels get into a better rhythm when they aren’t constantly having to deal with food.
- It promotes the growth of good gut bacteria.
- It reduces oxidative damage and inflammation.
- It slows down ageing of our cells and tissues.
- It switches on a number of cellular repair genes which means it has the potential to reduce the risk of cancer.
- It prolongs life in mice but we haven’t done the research on humans so we don’t know if that would also apply to us. I suspect it would.
Are there any psychological benefits of fasting?
- People tend to become more aware of their body. They get better at recognising whether or not they’re actually hungry or just reaching for food out of habit.
- People become more attuned to their body’s nutritional needs.
- Fasting makes us realise it’s OK to skip meals. It’s OK to feel hungry. You don’t have to grab the nearest fast food item that’s available.You learn to wait until you can have something that’s worth eating.
- Fasting teaches people to be more mindful when they eat. It’s a great way to enhance our appreciation of food.
Are there any dangers to fasting?
There are times when fasting is not recommended.
Please do not fast if:
- You’re a child or teenager – it can affect bone growth and onset of menstruation
- You’re pregnant or breastfeeding
- You’re trying to fall pregnant – it may reduce fertility
- You’re about to have surgery or recovering from surgery – don’t fast for a month either side of surgery because healing consumes a lot of calories. Therefore fasting may slow your recovery.
- You’re on medications that need to be taken with meals
- You’re on blood thinning medications like warfarin – it can increase your INR ie you will bleed too readily
- You’re a type 1 diabetic or a type 2 diabetic on insulin
- You have a fever, infection or are feeling unwell
- You’re underweight
- You have a history of an eating disorder like anorexia, bulimia or binge eating. There is a risk that fasting could trigger your past illness.
Please forward this Health-e-Byte to anyone who wants a simple way to boost their health.