For someone who’s life revolves around food & eating, I’ve always been a bit resistant to the concept of fasting. Growing up and throughout most of my life working as a dietitian & sports dietitian, the mainstream belief was that the ideal way of eating to maintain good health was to have 3 meals a day, starting with a good breakfast. Within this, there was a number of years where ‘grazing’ frequently over the day was encouraged, particularly for children and active people. Almost every meal plan I wrote for my athletes encouraged eating every 3 – 4 hours with at least 2-3 snacks a day suggested. Fasting was only a consideration for religious reasons, prep for surgery or blood tests, or alternative hippy retreats.
Fast forward to the last 5 or so years, and my perspective on how often we need to eat has definitely changed. Studies looking at intermittent fasting (having a very low kJ intake on alternating days or 2 days/week) and time restricted eating (eating within a limited time period each day – usually less than 8-10 hours) have shown a number of health benefits including improvements in insulin sensitivity and risk factors for heart disease, as well as body fat reduction in overweight people. It appears that during periods of not eating, the body is able to activate pathways that allow our cells to repair and regenerate. This can have long lasting health effects and may be a key to improving our metabolism, enhancing our immunity and slowing down the ageing process.
There is little doubt that many people in the western world overeat, usually mindlessly, often without hunger cues, and frequently food that is heavily processed playing havoc with our hormonal and gut health. In fact, the more processed the food we eat, the more food we tend to eat!
Different styles of fasting can offer an opportunity to allow us to connect with and appreciate food when we are eating, and to realise that we can go periods of eating quite safely, with a number of physical and mental benefits. Fasting has been shown to improve cognitive function and may even be useful in treating a number of neurological disorders.
What’s the best way to try fasting? Like most nutrition interventions, one size does not fit all, and it’s about finding an eating regime that works best for you at any particular time. Whilst longer periods of fasting (1-7 days) works for a number of people, many find that intermittent or time restricted approaches are easier to implement and maintain, and still provide the desired results.
It is interesting to note that much of the research on fasting has been carried out on men (which is not uncommon) and there is evidence that women need to look at this health hack a little differently. Women in their reproductive years are designed for fertility and reproduction, and fasting signals to the body that it’s not a good time to reproduce. Intermittent fasting can disrupt estrogen balance which in turn affects metabolism, weight control, mood, anxiety, energy levels, bone density and cognitive function. This doesn’t mean that women before menopause can’t incorporate fasting however it may mean that time restricted eating (e.g starting with a late breakfast and having an early dinner so that for around 14-16 hours you are not having any food) is a better option as it is more in harmony with the body’s natural circadian & hormonal rhythms.
Again, personal experimentation is the key to discovering what helps you feel good, and perform at your best. For example, many very active people & athletes may find that fasting is only useful at times when training is low as it is too difficult to meet high energy requirements otherwise. Fasting is not recommended or appropriate for children & adolescents, pregnant & breastfeeding women, underweight individuals or those with, or predisposed to, an eating disorder.
Personally, I have found that time restricted eating is easier to achieve than I thought it would be, and works for my active lifestyle. I can do early morning activity (surf, run, walk, gym) and then eat anywhere from 9 – 11 am. A snack around 2 – 3 pm will keep me going until we have an early dinner around 5- 6 pm. A few things I’ve learnt from doing this is that I am really ready to eat by mid morning and after the initial few weeks, the hunger pangs (ghrelin hormones) generally only start to kick in then, and this meal is really enjoyable. I also find that keeping my carbohydrate intake relatively low – particularly avoiding very processed and refined sources of carbohydrate – helps control fluctuating energy and hunger levels and makes this new eating pattern more comfortable to maintain. I’m finding this way of eating helps me maximize my mental and physical performance over the day, and I sleep better at night after not eating for 3-4 hours prior to bed time. Not every day works out this way, but I usually manage at least 4-5 days a week unless we have visitors staying or I’m travelling, or out of my usual routine.
I would like to think that I could do a fast for several days at some stage … but right now doesn’t feel like the right time for me – let’s face it, there’s just too much good food in our house!