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Five ways to kick-start fasting to improve your cognitive fitness
It's daunting to contemplate how to get started with intermittent fasting. It has become synonymous with keto and faddish diets and has elements of a cult - which turns people off. That's unfortunate because intermittent fasting can keep our brain functioning better for longer.
Here's how to get started, without having to "go keto" or remove yourself from family dinners.
The reluctance to make fasting part of our lifestyle is not helped by the fact that until this year (2020), intermittent fasting was yet to be assessed in a rigorous clinical trial. The publication of a small "rigorous clinical trial" - just 58 subjects - reported "weight loss and improved cardiometabolic measures".
Intermittent fasting (IF) diets fall generally into two categories: daily time-restricted feeding, which narrows eating times to 6-8 hours per day, and so-called 5:2 intermittent fasting, in which people limit themselves to one moderate-sized meal two days each week.
It's all about our brain
Why bother? We're doing this primarily for the potential benefits in slowing the aging of our brain.
Intermittent fasting may improve health and extend longevity (as mentioned above, still to be proven). Experts propose that health benefits from fasting occur by making the body switch to fat cells for energy. Fasting is also believed to induce nutritional stress that speeds up cell repair and renews metabolic function. This repair and renewal applies to the brain as well.
Dr Mark Mattson, a neuroscientist who recently retired from the National Institute on Aging, studied intermittent fasting for decades. A couple of studies in the 80s revealed that alternate-day fasting in mice extended their life spans by 30 per cent.
That finding made researchers wonder if there might be a connection between alternate-day fasting and brain function. Mattson tested this idea and found that intermittent fasting enhances the ability of nerve cells to cope with and resist the kinds of stress that lead to their degeneration.
Intermittent fasting also aids in the production of BDNF (Brain-derived neurotrophic factor) which is known to be critical for learning and memory. Which means that fasting does not just reduce physical degeneration of the brain but also improves its functioning.
In a nutshell, it seems that by putting our body through short-term stress we teach it how to use energy more efficiently and recover quickly. This requires "metabolic flexibility" - which requires training our body to use different food sources.
What is metabolic flexibility?
Within our cells, energy is provided by oxidation of foods such as carbohydrates, fats, and proteins, however, the rate of metabolisation of these nutrients can vary significantly.
Metabolic flexibility is our ability to switch back and forth between fat and carbohydrates based on their availability. In other words, it is our body’s capacity for adapting fuel demand (fats/carbs) to fuel availability (what we eat).
We can all switch between different fuel sources, but we favour those types of energy sources which we feed our system e.g. carbohydrates. Just like exercise, when there is no need to do it then the body becomes lazy.
We slouch on the couch, or we just keep absorbing what comes by in our bloodstream - whatever is easiest. That makes us inflexible, and metabolically our system becomes inflexible. This inflexibility is what makes it hard to adjust to intermittent fasting because the body struggles to adapt. It takes time, and we can have headaches and feel weak as adjustments work through our system.
Our body uses three sources of energy - carbohydrates, fats, and proteins:
There are 2 key factors involved in determining our degree of metabolic flexibility:
Individuals with great metabolic flexibility can readily burn both carbohydrates or fats when they eat them. Whereas metabolically-inflexible individuals struggle to efficiently use fats or carbs, which can lead to an excess of those in the body in the form of fat.
Little by little developing better metabolic flexibility allows our body to switch efficiently and quickly between different food sources.
Intermittent fasting is the process we use to train and to maintain our metabolic flexibility. And, in turn, metabolic flexibility allows us to adapt to intermittent fasting and to derive the benefits for our brain health.
Five kick-starter intermittent fasting ideas
Here are five ways to start to build intermittent fasting into your life, and hopefully help you to live longer better with a brighter brain.
To make this a lifestyle choice, and not a punishment, don’t try to make too big a change. You need to ensure that your daily eating window gives you enough time to consume a healthy variety of fruits, vegetables, legumes, nuts and plant oils, whole grains and protein.
For example, vegetables contain carbs, but there is no need to restrict vegetables or fruit in the changes you apply to gain metabolic flexibility. The main focus is timing, and a secondary focus to improve the nutritional quality of your diet.
You don't have to fast often in the beginning either. You may be more comfortable breaking in slowly with 2-3 fasts a week at first. Add additional days of intermittent fasting as you become more comfortable with this style of eating.
Intermittent fasting is not a diet. It is a timed approach to eating.
Kick starter #1 - Morning exercise before eating
If you walk or exercise in the morning, first thing, then consider having just water or a cup of black tea or coffee (no sugar) and nothing to eat beforehand. I do this before walking 5km or run 5km every morning. Then I hold off on having anything other than water until it becomes inconvenient for work or my day's calendar.
Doing this, and especially if you try not to eat after 8 pm, will create a longer fasting time between your last evening meal and your morning meal. It has the added benefit of your body needing to call for energy during your exercise and hence pushing your metabolism towards burning more fat.
Be on the lookout for side effects such as dehydration, irritability, mood changes, fainting, hunger, a lack of energy and being unable to focus. If these are happening then you may need to exercise less intensively or eat a carrot or orange or apple 15 minutes before exercising.
Kick starter #2 - Skip breakfast a couple of times a week
I'm a breakfast eater, so this one does not suit me. But if you are not a breakfast eater then get a routine going whereby you skip breakfast totally a couple of days a week. Make it fit your lifestyle. You probably don’t want to do it on the weekend, and if you meet friends on the way to work that's probably not a good day either.
By the way "skipping breakfast" means eating no carbs until lunchtime, especially it means no sugar with coffee for example, and no snacks. Keep training your body to switch to fat burning.
I follow the idea that our body processes food more easily in the morning due to the insulin cycle. When you eat a meal, you have what's called a thermogenic response, where your body produces a little bit of heat. You do that more readily in the morning than you do at night.
This is because insulin works really really well in the morning, and then it starts to not work so well in the afternoon, and it doesn't work so well at night. In other words, our bodies seem set up to process food more favourably in the morning than at night.
So although I am a fan of exercising fasted first thing in the morning, I do like to have a good protein and healthy-fat-oriented (avocado) breakfast each day.
Related: Why Skip Breakfast When You Can Eat This And Improve Your Health?
Related: Skipping Breakfast May Make You More Likely To Develop Diabetes — Research
Kick starter #3 - Eliminate most carbs twice a week
Bearing in mind that you can eat as many vegetables as you want, try having two protein and healthy-fat-dominant days twice a week - two in a row is good.
Eat eggs, meat, fish, tofu, eggs, avocado, with vegetables. You can eat a lot of vegetables before reaching 20 grams of carbs, and add some colourful peppers and tomatoes. Here is Dr Diet Doctors Low Carb Diet For Beginners.
Maintaining this, if it is different from your normal diet, will kick your metabolism into a new gear. You may feel tired, and get a headache. That's a good thing, it shows that your metabolism needs to tune itself up.
Kick starter #4 - 12 hour fast twice a week
12/12 intermittent fasting is simple, safe and sustainable.
If you are comfortable with fasting for 12 hours, then kick-off two days a week. Work out a pattern of not eating for 12 hours on two days, which suits your lifestyle. Typically people start from the night and go through until lunchtime the next day. You'll find a myriad of advice on how to do this - just remember to keep drinking fluids, without added sugar.
Others opt to eat between, say 6 a.m. and 6 p.m., which allows plenty of time for a healthy breakfast, a normal lunch around noon and a light early dinner or snack around 5 p.m. before starting your fast.
Kick starter #5 - One meal a day
The OMAD plan is as simple as it sounds. Pick the mealtime that you enjoy the most, and have a healthy nutrient-dense meal and make it that one meal for the day.
You can have vegetables others times, like a fresh carrot. Liquids without added sugar are fine.
You can choose to do OMAD for one or two days a week, and then over time, you may add more days.
Progressions - where to from here?
What you do next depends on how you feel when you try these various types of intermittent fasting. Remember, these are all kick-starter tips to get you used to the feeling of fasting, and to how your metabolism reacts. Each of us reacts to fasting is very different, so you need to feel it out for yourself.
You might want to do more of the same, more often. You might want to mix it up. You might be emboldened to go hard-core and do a full 5:2 five-days on 2 days off regime.
Whatever you choose, you have made progress in stimulating your metabolic flexibility, and in kick-starting your journey to a healthier brain.
> More posts to help you with EXERCISES
> More posts to help you with DIABETES
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Since I was diagnosed at 50 with Type 2 diabetes I've been learning how to do bone-building fitness training which lowers my age. You can too. It's your choice. Walter