If you read articles about intermittent fasting on the net you'll quickly realise that it is regarded as a valuable tool for improving health with benefits like: increased longevity, weight loss, reduced blood pressure/cholesterol, controls eating habits, builds muscle tissue, shifts the body to fat burning and so on. Have a look at Dr Mercola's take on intermittent fasting here.
How Does Fasting Work?
Energy requirements entirely depends on the individual and factors like lifestyle, sex, age, health etc but the body may take around 12-24+ hours to use up glycogen stores within the liver for energy. Glycogen is the storage form of glucose found in the muscles and liver and is the preferred source of fuel for the body's energy needs. When the body has used up its glycogen stores then the next line of fuel is to break down and utilise fat stores for energy. So one of the ideas of fasting, is to give the body enough of a break from eating so that it can shift into fat-burning mode. Most modern day eating patterns do not leave this length of break from eating.
There are Lots of Styles Of Intermittent Fasting - It's confusing
There are so many styles and variations of intermittent fasting based on the number of fasting days in the week. This is known as weekly intermittent fasting, of which there are many variations:
- 1 fasting day in the week (continuous 24 hours), leaving 6 non-fasting days in the week
- 2 fasting days in the week, leaving 5 non-fasting days in the week (fasting days are usually spaced out with eating days). Also known as 5:2 diet
- 3 fasting days in the week, leaving 4 non-fasting days in the week (fasting days are usually spaced out with eating days). Also known as 4:3 diet
- 4 fasting days in the week, leaving 3 non-fasting days in the week (fasting days are usually spaced out with eating days).
Then there are also variations of daily intermittent fasting, which are based on fasting for 14-18 hours in the day leaving a non-fasting window of 6-8 hours in a 24 hour period. This is typically achieved by eating the last meal in the evening and then fasting, skipping breakfast and making lunch the first meal of the day.
During Intermittent Fasting is there a Complete Abstinence from Food and Drinks?
Intermittent fasting is not usually a dry fast (no liquids). During fasting periods, water and other non-calorific drinks are consumed like herbal teas, tea and coffee. I personally don't like the ideas of using caffeine-containing stimulants like tea and coffee to boost blood sugar levels. This may lead to too much adrenal stimulation and may lead to imbalances with adrenal functioning. Some people also include zero-calorie sugar-free drinks in the fasting period. Sugar free but sweet-tasting sweeteners like aspartame containing drinks, sugar-alcohols like xylitol etc trick the brain and body into thinking it is digesting a carbohydrate, with the expectation of glucose release for energy. Aspartame has many associated health risks and xylitol may contribute to IBS.
What is Consumed during Non-Fasting Periods?
Again in the allowed eating window, there is a huge variation of what to eat like ingest a 'normal daily calorie intake', ingest a 'reduced' calorie intake, 'eat what you want', 'fruits/vegetables', 'vegan', 'low carbs', ' high fat/protein', 'paleo', 'clean-foods' and so on. I think that an individual's health, energy needs and lifestyle should always be factored in to plan out a sensible eating plan.
Are There any Precautions and Contraindications?
Contra-indications for intermittent fasting have been found for individuals who have issues with blood sugar like hypoglycaemia, adrenal fatigue and diabetes. Also women may not do as well as intermittent fasting may overdrive their stress hormones and interfere with sleep and menstrual cycles. Another issue is that intermittent fasting may also encourage disordered eating/obsessive and compulsive behaviours for certain individuals. Also, if you are pregnant or nursing then fasting should not be done.
My personal feeling is that as there are lots of variations of fasting styles and differing opinions of what to eat during non-fasting periods. this means there is the potential for it to be a bit hit and miss depending on what sources you read. At best intermittent fasting could be a positive tool with many health benefits and at worst it could negatively impact health and well being. So if it's not worked for you, please don't see it as a failure on your part, it may need tweaking to suit your individual metabolism, life style, emotional makeup and so on.
I do however think there are a lot of positives to intermittent fasting, so I've come up with some guide lines, if you want to give it a go.
- If you have blood sugar issues, like hypoglycaemia, diabetes, chronic fatigue, adrenal fatigue and so on then this needs to be supported before considering intermittent fasting. You should seek the help of an experienced health practitioner and realise that it may still be contraindicated. However gentler approaches of the intermittent fasting may be considered but again seek advice and help.
- During the fasting period, if you are finding it hard then try drinking a small glass of coconut water (good source of electrolytes) or take a teaspoon of virgin coconut oil (good energy source which may be metabolised by the brain as an alternative energy source to glucose)
- During the fasting window, consider fluid intake wisely. Do not over drink water as it may stimulate a loss of essential electrolytes. As a general guideline around 1 medium cup/glass of water in an hour should be ok. Consider drinking mineral-rich low calorie drinks like bone broth, vegetable and/or seaweed based broth, green leafy vegetable juices, celery juice, cucumber juice, nettle tea etc. Mineral-rich drinks will help reduce headaches and will support blood sugar and help prevent it from dropping.
- Exercising during the fasting period may be beneficial too, so consider incorporating exercise like walking, yoga etc. Studies have shown that it helps to shift the body to fat-burning mode.
- During the eating window, consume easy to digest foods, clean foods. So stay away from junk/processed foods and foods containing sugar, refined salt, highly processed vegetable fats/oils and so on. See this as an opportunity to eat health-promoting foods.
- Also in the eating-window, spread your meals out, which helps stabilise your blood sugar. Make sure you are not going to bed on a full stomach, by abstaining from eating a minimum of 2 hours before going to bed.
Finally, really listen to your body and use nutrition to support your individual health needs.