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Intermittent Fasting



A couple of years ago, I wrote about fasting in a blog during Advent, since this is traditionally a time of fasting in the lead-up to Christmas (similar to Lent in the lead-up to Easter). I looked at the different kinds of fasts people have done in the past, from intense fast of 40 days drinking only water (although this is physically possible, I don’t recommend it!) to more manageable fasts in which you skip one meal during the day. You might like to read over the blog here.

I said it would take a whole extra blog to deal with this topic properly…and, as promised, here it is! This time it is summer, but I think it is a good time to revisit this topic because if you are anything like me, you probably eat a bit less during summer when the hot weather makes smaller portions of food and liquids more appealing!


Intermittent Fasting

First of all, let me say that this blog will focus on one kind of fasting in particular which seems to give the most benefits with the least hassle or inconvenience. Let me introduce you to intermittent fasting. You may have heard of it!

There are two main ways to incorporate intermittent fasting into your life:

  1. Intermittent fasting each day. This is also called the 8-16 diet because it is based on eating for 8 hours of the day and fasting for 16 hours.
  2. Intermittent fasting each week. This is called the 5:2 diet because it is based on eating normally for 5 days and eating heavily restricted calories for 2 days.

I personally find the 8-16 diet easier because it fits into my life without too much disruption, but everyone is different and what suits me may not suit you! It is worth talking it through with me in your consultations to find out what will work best for you.


How does intermittent fasting affect your body?

Intermittent fasting changes your body in fascinating ways. As you fast, blood levels of insulin drop significantly and your body begins to burn more fat. During long fast periods, your body will go to its fat stores for energy, and fatty acids called ketones will be released into the bloodstream. Ketones promote positive changes in the structure of synapses that are important for overall brain health. Your growth hormones will increase to facilitate fat burning and increase muscle mass. Your cells will work harder to remove waste material and show an increase in cellular repair processes. Overall, a range of animal and human studies show intermittent fasting can result in reduced oxidative stress, reduced inflammation and a reduction in blood sugar levels and insulin resistance. Who would have thought such a simple change could pack such a punch?!


What are the benefits of intermittent fasting?

Let’s look at how your body benefits from these changes:

  1. Repair and regeneration! First and foremost, intermittent fasting gives your body a break from the hard work of digestion and gives it a chance to focus more on repairing itself. This is good news for our gut bacteria as well because intermittent fasting gives beneficial bacteria a chance to rest and recover! In 2015, a study on mice showed that fasting may rejuvenate the immune system, reduce the risk of cancer and improve brain function, concluding that in humans it could reduce the risk of age-related diseases.[1] In 2016, another animal study found that intermittent fasting reduced inflammation and autoimmunity generally, as well as the symptoms of MS in particular.[2]
  1. Decreased appetite! Many people who incorporate intermittent fasting into their lives are surprised at how easy it is to sustain. They also report that they have less desire to eat large meals or consume unhealthy snacks. A study published in the British Journal of Nutrition in 2013 found that men who worked out without eating breakfast (ie, exercising on an empty stomach) burned more fat than men who ate breakfast before exercising. Furthermore, they did not experience increased hunger or consume more calories later in the day.[3]
  1. Healthy brains! Intermittent fasting has been shown to protect brain functionality and slow down disease processes in the brain. In animal studies, intermittent fasting results in the growth of new nerve cells in the brain and studies suggests that intermittent fasting protect against brain damage due to strokes and against neurodegenerative diseases such as Parkinson’s and Huntington’s disease.[4] In 2014, a series of case reports showed that daily short-term fasts were able to significantly improve Alzheimer’s symptoms in 9 out of 10 patients.[5]
  2. Long life and good health! Studies show intermittent fasting can enhance the body’s resistance to oxidative stress and help fight inflammation.[6] In one animal study, rats that fasted alternate days lived 83% longer than rats who did not fast at all.[7]


It makes sense that intermittent fasting could help you live a healthier and happier life and it is a simple, easy change you can make without spending lots of money or creating too many difficulties for yourself. I have found it simplifies my life quite a lot whenever I choose to delay my breakfast until after midday: I have one less meal to think about that day! After my morning coffee, I find I can easily work through the morning until lunchtime when I eat normally. Interestingly, restricting my calories in this way also helps me sleep better at night!

If you would like to explore intermittent fasting more, please talk to me about it. I would love to hear your stories if you already do this on a regular basis!


Every blessing,



Emma Maitland-Carew – Registered Nutritional Therapist

Dip.ION, mBANT, CHNC Registered Practitioner,

Metabolic Balance® Coach, HeartMath Coach.


Further Reading

 For more about intermittent fasting you might like to read Kate Harrison’s The 5:2 Diet (2013) and Jason Fung’s The Obesity Code (2016).

If you are interested in other kinds of fasts you might like to revisit the Horizon TV documentary Eat, Fast and Live Longer with Michael Mosley from 2013.[8]

You might also like to read about one man’s experience of a long 6-day fast.

You can also read further in these recent studies:

Effect of Alternate-Day Fasting on Weight Loss, Weight Maintenance, and Cardioprotection Among Metabolically Healthy Obese Adults: A Randomized Clinical Trial. JAMA Internal Medicine, May 2017.

Intermittent fasting interventions for treatment of overweight and obesity in adults: a systematic review and meta-analysis. JBI Database of Systematic Reviews and Implementation Reports, February 2018.

Metabolic Effects of Intermittent Fasting. Annual Review of Nutrition, August 2017.

Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes. Cell Metabolism, May 2018.

Impact of intermittent fasting on health and disease processes. Ageing Research Reviews, October 2017



[1] Brandhorst, S. et al., 2015. A Periodic Diet that Mimics Fasting Promotes Multi-System Regeneration, Enhanced Cognitive Performance, and Healthspan. Cell Metabolism, 22(1), pp.86–99.

[2] Choi, I.Y. et al., 2016. A Diet Mimicking Fasting Promotes Regeneration and Reduces Autoimmunity and Multiple Sclerosis Symptoms. Cell Reports, 15(10), pp.2136–2146.

[3] Gonzalez, J., Veasey, R., Rumbold, P., & Stevenson, E., 2013. Breakfast and exercise contingently affect postprandial metabolism and energy balance in physically active males. British Journal of Nutrition, 110(4), pp.721-732.

[4] Fann, D.Y.-W. et al., 2014. Intermittent fasting attenuates inflammasome activity in ischemic stroke. Experimental Neurology, 257, pp.114–119.

[5] Bredesen DE., 2014. Reversal of cognitive decline: A novel therapeutic program. Aging, pp.707-717.

[6] Mark P. Mattson, Ruiqian Wan, 2005. Beneficial effects of intermittent fasting and caloric restriction on the cardiovascular and cerebrovascular systems, The Journal of Nutritional Biochemistry, 16.3, pp.129-137.

[7] Goodrick C, L, Ingram D, K, Reynolds M, A, Freeman J, R, Cider N, L., 1982. Effects of Intermittent Feeding Upon Growth and Life Span in Rats. Gerontology, pp.233-241.

[8] Mosley, M. & Spencer, M., 2016. Welcome to 5:2 intermittent fasting » The Fast Diet. The Fast Diet. Available at:


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