Not specifically a diet per se, intermittent fasting is a pattern where you restrict your eating to certain time periods of your day or implement strategic brief periods of fasting.
The aim here is to give your body a ‘break’ from eating, however – is the weight worth the wait?
What is Intermittent Fasting?
There are many different ways to try intermittent fasting, however they are all based around the idea of fasting for certain periods whilst eating at other periods. This can be done through methods such as restricting your eating window or restricting caloric intake.
In most cases, caloric restriction is also a result of narrowing your eating window. After a certain amount of time without food, your body runs out of the glucose (from your last consumed meal) that it uses for its primary fuel source which results in switching to burn fat for energy.
Here are a couple of different approaches to consider when thinking about trying intermittent fasting.
1. The Daily Approach
The daily approach means that you are consistently fasting on a daily basis. Some popular time windows include 12:12 (fasting for 12 hours and eating for 12) or a slightly more intense 16:8 (fasting for 16 hours and eating for 8).
These options can be good for beginners, especially if you are someone who is not hungry for breakfast.
A daily meal plan for this approach may look like (using the 16:8 as an example):
- 8AM: Black coffee (adding milk or sugar would be breaking the fast!)
- 12PM: Breaky bowl with quinoa, sauteed greens, poached eggs & smoked salmon
- 3PM: Raw ball & a banana
- 7PM: Chicken curry with brown rice.
- 8PM: Herbal tea
2. Fasting for 2 days per week
Also named the 5:2 diet, this approach is centred around eating regularly for 5 days of the week whilst limiting the other two days to one small meal (approximately 500-600 calories). For example, eating normally most days then eating one small meal on Tuesdays and Thursdays.
3. Alternate Day Fasting
This method involves fasting every other day, including either a small meal (up to 500 calories) or a complete abstinence from food altogether. This is certainly an affective form of fasting for the goal of weight loss, however long-term maintenance may be unsustainable.
4. Flexible Meal Skipping
This is probably the most maintainable approach for beginners. The flexible meal skipping approach simply focuses on the fact that sometimes you may not be hungry for a meal, despite it being a regular meal time. It allows for individuals to respond to their individual hunger and fullness cues and is perhaps a more natural way for individuals to implement fasting into their routine.
5. Extreme Fasting
The Warrior diet or 20:4 diet is an extreme type of fasting where you fast for 20 hours of the day and eat for 4 hours in the evening. This type of fasting is generally only advised under the guidance of a health professional and only if you have tried another type of fasting before.
It is designed to mimic ancient warrior eating patterns – where people spent their days actively hunting and gathering before a large evening feast. However, the long period of fasting may potentially come with an array of side effects, is difficult to sustain and may promote a poor relationship with food and/or binge-eating behaviours.
The Benefits…
As you can see, the intensity of fasting differs immensely in its implementation. However, the benefits have been proven amongst many studies for an individual’s body and brain.
• Improves Healthier Blood Levels
Achieved in a simple night fast, blood glucose and insulin levels are lowered which is associated with an overall lower risk of chronic disease such as certain cancers and coronary heart disease (1).
• May fast-track Weight Loss
Weight loss is probably the most common reason for intermittent fasting, if not any diet! I mean it makes sense – eating in a smaller window of time will make you eat less, right? Well, lower caloric consumption isn’t the only reason for this. Once your body uses up all the fuel from its last meal, it begins burning the glucose and fat stored in your body. Meaning, intermittent fasting supposedly helps at both sides of the calorie equation – boosting your metabolic rate (calories in) whilst reducing the amount of meals consumed (calories out) (2).
• Cognitive Benefits
Research suggests that intermittent fasting improves cognition, memory and may even slow ageing processes in the brain (3).
• Quicker Healing & Reduced Inflammation
Intermittent fasting may enhance the body’s resistance to oxidative stress and help to fight inflammation (4). In addition to this, the cells in the body initiates autophagy which involves cells breaking down dysfunctional proteins that accumulate in cells over time. The combination of these factors mean that the cellular processes in the body are constantly rejuvenating themselves, which in turn gives more energy to healing processes and maintaining optimal health.
But, is it safe for everyone?
Intermittent fasting is not for everyone. Certain individuals may not be suitable for intermittent fasting, including:
- Pregnant or breastfeeding women
- Those with a history of eating disorders
- The elderly
Females in general should be hesitant to try intermittent fasting, as it may disrupt female hormones. Although the research isn’t clear on this as of yet, it is important to note that female hormones are sensitive to low caloric intake. This means that the key functions related to ovulation, reproduction, metabolism, and mood could potentially be blunted.
Particularly, intermittent fasting may decrease oestrogen which has an array of side effects to the female body including decreased bone density, increased appetite and an increased propensity for fat storage. However, this may be overhauled as long as appropriate calories are consumed.
In any case, it is always a good idea to talk to a doctor or nutrition professional for anyone prior to implementing any kind of intermittent fasting.
So, should you try intermittent fasting?
Look, intermittent fasting is not a magic pill – nor is any other diet. It is still important that you follow a healthy, balanced diet whilst following the protocol. Eating junk food and excessive calories on the days or hours that you aren’t fasting will not result on the benefits stated.
Considering that you are not on the ‘unsafe’ list mentioned above and are serious about trying intermittent fasting, I would advise proper research and/or adequate guidance from a health professional. As a holistic nutritionist, I aim to provide you with the tools and knowledge to make informed decisions about your diet so that you can take your health into your own hands. If you are eager to take the next step, click here to book an Initial Nutrition Consultation.
Written by:
Mollie Caughey-Wade,
Clinical Nutritionist (BSc).