Friday, April 29, 2016

Low-carb for life?


It's been long since my last article. A big thanks to all the people that kept reading and sharing my blog during the last months. The statistics are clear: I received an average of 50 visits per week from all over the world including countries I never intended to reach, which is not bad at all for a blog that hasn't been updated for 6 months! This makes me really motivated to restart writing.

Today I stumbled upon this article on the benefits of a low-carb lifestyle, with particular reference to high-performance training while in ketosis.

Low-carb diets live periodical periods of popularity, sometimes longer sometimes shorter. They seem to be very in vogue these days and many people are going low-carb or even zero-carb, often following the recommendations of a gym pal for whom it worked.

Let me first say something: I am one of those who believe that the food pyramid is completely wrong and the base should not be made of starchy carbohydrates, followed by sugars, up to a tiny pyramidion on the top to represent fats. Carbohydrates are indeed important, but so are fats and proteins, as I explained in my article on balance.

Back to the article that convinced me to return to animate this blog, I agree with most of the points, but there are some important details worth adding.

First, the things I agree with


Massively increase the fat you burn
[...] our energy stores are deeper if you’re running on fat

Both are obviously true, being fat-adapted is wonderful: I am fat-adapted myself although I avoid ketosis (it gives bad breath and the sweat smells like nail polisher).
The good news is that you can still be a fat burner while staying on a “moderate carb diet”. Let me paraphrase this: you can get the best from both worlds and this is even more wonderful than being in ketosis: humans are equipped with an hybrid engin and as such this is how we should use it.

You hold less water weight on a low-carb diet.

True with a caveat: you must eat healthy fats, which is what saturated fats are anyway. Rancid and oxidised poly-unsaturated fats will cause inflammation and consequently water retention. This is the reason why the paleo diet doesn’t work for those doing it wrong (paleo bread, paleo muffins, paleo pizza crust…). Eat real food!

Get your carbs from non-starchy, nutrient-dense veggies
like broccoli, bok choy, fennel, and kale.

The second part is common sense and as my clients know, this is what I preach.
The first part, avoid starches, is half-true: they should be avoided when you are inactive, but are almost a must after (and not before) an intense workout. Glycogen stores in the muscles and possibly also the stores in the liver are depleted, that’s the ideal moment for a reasonable carb-refill: insulin sensitivity is at its top, you’ll spare aminoacids and the little insulin produced will promote muscle repair and growth.

But now the interesting part.

The dark side of being low-carb…

… especially when protracted for long periods and even more if you are into a high-intensity physical discipline.

1. Adrenals health

Low blood sugar triggers a response from the alpha-cells of the pancreas to release glucagon, this very important hormone helps in maintaining glycemy within acceptable ranges. Constantly low blood sugar levels caused by a low-carb diet sometimes are too much and, just like the beta-cells of the pancreas that release insulin to remove sugars from the blood, the alpha-cells can slow down. Enter the adrenals.

The adrenals are emergency glands, despite being small they play several fundamental roles to keep us alive. Critically low blood-sugar levels are indeed an emergency (you may go comatose…), and the adrenals respond by producing cortisol and adrenaline.

The first is an anti-inflammatory hormone, so far so good. It also activates the liver to convert fats and amino-acids (and therefore proteins) to produce glycogen through a process called gluconeogenesis. In other words, it impairs muscle growth and potentially triggers muscle break-down. I am not sure how studies can show that being in ketosis promotes muscle growth in the long period. My take is that other factors play a role in this, like the fact that fasting activates the release of HGH but again: you are cheating your endocrine system to bulk-up, are you sure you want to do this on a regular basis?

Adrenaline, too, activates fats conversion in the liver (good news: it doesn’t break down amino-acids), it also impacts the brain by raising alertness, this is the reason why, once you are truly fat-adapted, fasting gives you mental clarity. It is an highly addictive sensation so I am not surprised that many low-carbers feel so enthusiastic about their peculiar diet. And if this were not enough… caffeine by-passes all processes and directly stimulates the adrenal glands to produce more adrenaline. And the disaster is just around the corner, the two poor emergency glands that Nature intended to be reserve soldiers, are now fully employed on the front line in a fight for survival. The biggest problem of long periods of low-carb (and excess of caffeine, the two usually go together) is that adrenals too may fail: they are emergency organs and should be used occasionally, if you keep over-stimulating them why shouldn’t they fail?

Adrenals also produce sex hormones, in particular testosterone. If you keep them busy producing cortisol and adrenaline (emergency hormones) they won’t bother producing libido-enhancers, that’s definitely not the right moment. This is dedicated to you guys: having a belly that looks like Batman’s carapace is useless if… (I let you finish the sentence). My case is well supported by a consistent number of guys complaining about this on several forum. By the way, it is perfectly possible to show a 6-pack even on high-carb diets, as several vegan athletes seem to confirm.

2. Thyroid health

I will never repeat it enough: the food you eat is not just calories and anti-oxidants. When you eat you are sending messages to your body which will respond accordingly.
Low-carb diets are a clear message that famine is coming: less variety is never a positive sign. So it is time to down-tune the metabolism in order to burn less. One of the many ways to burn less is to limit the thyroid output which, as some of you may already know, is a situation where you don't burn body fat anymore, no matter how little you eat.
In addition to a reduced output from the thyroid, the liver also needs glucose to convert T4 into T3. Low carb diets will definitely make you lose weight quickly in the first weeks/months. You’ll get it back later with the interests.

3. Insulin resistance

Yes, as strange as it seems, your muscle cells can become insulin resistant not only by eating too much sugar (for periods too long), but also eating too little of it (for periods too long). This mechanism is designed to save glucose for the brain and from a survival point of view this makes sense big time: it is more important to avoid going into coma rather then outrunning Usain Bolt in the 200m.

Final words

For decades we have been told that fats are bad. Fortunately, recent studies and the honest reanalysis of old studies that have been deliberately hidden because they didn’t conform with Common Wisdom, are putting this fad to an end. Although people still find counterintuitive that eating fats won’t make you fat, there is a growing awareness of this and that can only be a good thing.

On the others side, it seems humans can’t live without a villain to hate, it must be evolutionarily hardwired in our brains. This time it is the turn of carbohydrates: will it last just some years or, like it happened with fats and cholesterol, shall we re-discover ourselves sicker than ever in 4 decades from now?

I am back writing: stay tuned, do you exercises dutifully and have some baked potatoes with your roasted duck!