Fasting is popular, but is it effective? Here's my thoughts...

You hear of entrepreneurs and aspiring high performers discuss how they delay breakfast. "It offers a sense of mental clarity, focus and therefore increased productivity". But is this an effective strategy? Should you be doing it?

Other potential advantages reported by the pro-fasting crowd are that it helps with weight loss, as well adding a level of convenience and time saving associated with not having to cook, eat and then clean up.

The general notion is that it is beneficial to avoid food in the morning, delaying it until after you have completed an intense and focused work block and potentially a bout of exercise.

I did a poll on my instagram page this week and as many as 45% said that they do some form of fast!

• 24% said that they do it for focus and concentrating

• 14% said that they do it for fat loss

• 33% do it for convenience and time saving

• 29% said that they simply forget to eat in the mornings

Now, whilst there are reports of intermittent fasting being protective of developing neurological disorders (Parkinson's, Alzheimers, Epilepsy, Multiple Sclerosis), there appears to be no short term positive benefits on cognitive function (Gudden, et al. 2021)

However, this doesn't mean I'm against it. In fact, I'm neither for or against it, I'm somewhere in the middle… because, as usual, "it depends!"

Before you roll your eyes at my cliche answer, allow me to explain and offer you some principles to take away.

Neurons, or nerve cells - unless you're in a ketogenic diet - really thrive on glucose.

Your ability to think, focus and make decisions is actually enhanced, a lot, by having sufficient glucose in your bloodstream and, therefore, brain.

So why do people report a heightened state of mental focus when they are delay their breakfast?

It's simple really…

When we ingest food, there's a shift in our nervous system towards a parasympathetic state. This, ultimately makes you feel more relaxed and can make us feel lethargic, if not, certainly less 'switched on'. Too add, consuming food can also cause blood shunting to our gut which can also reduce our focus and contribute to a varying degree of sleepiness.

Caffeine may also be a little more impactful when consumed in situations where blood glucose levels are lower, also.

Ultimately, fasting doesn't necessarily increase your focus. Instead, it reduces the symptoms of tiredness and sleepiness that comes with eating.

It's worth noting, however, that these symptoms are directly linked with what you eat, and how much.

Key points:

• The larger the portion you consume, the greater the lethargy is likely to be.

• The greater the contribution of carbohydrates to that meal, the more Serotonin your body will produce and therefore push you into that parasympathetic state.

• However, if that carbohydrate consumption elevates your blood glucose levels to or even beyond your ideal baseline, you may see improvements in your focus and concentration.

• The greater your blood glucose rises, however, the more you are likely to experience a crash soon after. It becomes a false economy.

So what's the deal? It all still sounds very confusing and contradictory!

On one hand, your blood glucose being low because of fasting allows you to think and behave in a very concentrated way.

And on the other, having sufficient or slightly elevated blood glucose, allows you think really clearly because your brain is nourished.

Being fasted is great for focus and concentration.

Being fed is terrific for focus and concentration.

The solution lies in what you eat, how much you eat and when you choose to eat it.

If you like to fast, then fast. But be mindful of the size of the meal you consume and to what extent that carbohydrates contribute to the total kilocalories in that meal. Im not suggesting you avoid carbohydrates here, but it might be worth focusing a little more on proteins, fats and fairly low to moderate carbohydrates.

If you'd prefer to eat in the mornings, then do that too. Again, just be mindful of the size of the meal and to what extent you consume carbohydrates, or rather, how it affects your blood glucose levels.

I must add, that I am not part of the anti-carbohydrate crowd. They're essential, in my opinion! But timing and distributing them appropriately, depending on your goal, is important.

Perhaps a combined approach is more useful and effective, in comparison to being so rigid as to whether you fast or you don't. After all, it doesn't matter how disciplined you are… if you're experiencing hunger, none of the above mechanisms matter all that much; you won't be able to focus and concentrate as well if all you're thinking about is your first meal of the day.

So listen to your body.

What I would say, for sure, is that if you're overweight because fasting is causing you to reach into the snack cupboard at 2200hrs, then it doesn't matter whether you think you'll focus more when fasted, or not. The above advice is irrelevant if you're metabolically unhealthy and therefore unable to manage your blood glucose levels regardless of your preference in meal timings.

• Always prioritise your progress toward a healthy body composition.

• Control for total daily kilocalorie intake, regardless of the method.

• Hydrate well.

• Limit your caffeine intake.

• Avoid alcohol.

• Work hard to ensure sufficient sleep quality and quantity.

These six points will always have a greater impact on focus, mood, concentration, productivity and long term health over any nuances.

So what would I recommend that you do?

Well, if you want to fast, and doing so doesn't increase the likelihood of you wanting to eat unnecessarily later on in the day… then do it! However don't assume that fasting provides you with an edge, because it absolutely doesn't.

A significant downside of fasting, is that it'll make it harder for you to consume adequate animal protein throughout the day. It'll have you play catch up and no doubt make it extremely difficult to consume enough.

Ideally, you may want to consume 40-50g of protein in each of the 4-5 meals you should for optimal physical, physiological and psychological health. Fasting will only make this much harder.

Personally, if I can't access good food in the morning for whatever reason, then I know fasting isn't bad and that it is a strategy that I can utilise without any issues.

I'd prefer that Op Rebuild members and I eat, however. They key to preventing lethargy and reduced focus whilst optimising concentration and mental clarity during intense work periods, is to prioritise SMALL meals comprising of animal proteins and good fats before, during or after focused work blocks.

You may remember me saying that neurons thrive on glucose.

The consumption of carbohydrates can be a super power if you get the timing right.

Whilst a subtle dip in focus and energy may come a little while following the consumption of carbohydrates, it's likely that this won't occur until after a surge in energy, concentration and mental clarity.

When I notice my concentration dipping a little after 2 hours plus of deep work, having only consumed animal proteins and good fats, I'll always initially prioritise a short 20 minute 'headspace walk' outside in the fresh air and natural light, however if an added boost was needed here, I would be considering the use of carbohydrates, which may come in the form of fruit, rice, maple syrup, honey, jam and/or rice cakes.

To conclude, there is nothing special about fasting! Least not when it comes to cognitive performance and fat loss, anyway.

That's not to say that its bad either, just make sure you're still able to consume enough nutrient dense sources of protein.

Ideally, however, I would recommend that for the most part, you eat. But if you're wanting to optimise focus, concentration and mental clarity, then be very particular about what you eat, how much you eat and when you eat it.