If your diet is working, it's probably because of this

In my beginning days of nutrition, I was always looking for that "one thing".  

Read an article, that one thing is eliminating carbohydrates.  Saw a video, it actually comes down to eating carbs at night.  Wait a sec, read a newer blog by the same author, now it's actually fasting that is the one thing I should be doing. It's always something you aren't already doing and it's usually "one thing".

That thing I was looking for was a loophole. You might be looking for the same.

It's not that simple

Physiology is complex.  Nutritional biochemistry (digestion, absorption, assimilation of nutrients) is complex.  

However, for us, our inputs are pretty simple. We can eat a sandwich or a salad and not think twice about the transport of fats in our lymph tissue, blood glucose disposal or transit time of digestion.  We can feel pretty good or pretty lousy after a meal and make an adjustment to what we eat based on our energy and satiety and never get more hands on than that.

Making a diet change to lose weight or gain muscle is similar in this regard.  Most people are executing an idea like "skip breakfast" or "don't eat at night" without any understanding of the mechanisms at play internally.  Not that most of us need to anyway. However, the lack of understanding also makes us susceptible to fun or exciting nutrition ideas that seem to provide a shortcut while only asking us to do one thing.

Some people need to reduce carbohydrates; and I don't mean just as a way of reducing calories but specifically because they have issues with blood sugar management.  For those people, reducing carbohydrates provides a specific health benefit because of a disregulation in their physiology.  For just about everyone else, reducing carbohydrates is simply a way of reducing calories.

This point is often lost.

Ketosis is a great example of this.  It's exciting to think that simply reducing insulin via reductions in carbohydrates means effortless fat loss.  While insulin DOES work to store energy in tissue (like fat, liver, muscles) and downregulates fat burning, it's not the only mechanism at work.  First of all, you don't need insulin to store fat in at cells. There are enzymes that work to upregulate lipogenesis (fat storage) in the absence of insulin.

Secondly, carbohydrates are very rarely converted to lipids to be stored as fat.  You can store some glucose in fat cells of course, but the majority of carbohydrates are stored in liver/muscles and preferentially used for energy. Unlike fat, carbohydrate use for energy is correlated with how much you eat.  Essentially, eat more carbs, burn more carbs.

But fat intake does not work the same.  Eat more fat does not mean burn more fat. If this is true, then why do drastic reductions in carbohydrates lead to weight loss in some people?  The answer is because some people make a large enough reduction in carbohydrates that they are in a calorie deficit.  Since carbohydrate intake is low (and thus reliance for energy is low), fat is preferentially used as fuel for energy production.  Eating more fat does not mean you burn more fat, people tend to eat more fat on a low carb diet and plenty of people do not lose body fat doing this.  The ones that do might be eating more fat but the drop in carbohydrates might still create an OVERALL calorie deficit, leading to weight loss.

In a an often experienced (but nonetheless confusing) situation, someone adopts a low carb/keto diet and sees weight loss but does not see fat loss.  I've seen this with plenty of clients; they ditch bread and pasta and fruit but end up eating cups of almonds, heaps of peanut butter, lots of cheese, oil and fatty protein instead.  Fat is more than twice as calorie-dense as carbohydrates so quite often people don't experience any calorie deficit ona low-carb diet because they've simply replaced their carbohydrate calories with fat calories.

So how does the weight loss occur?  This one is actually relatively simple: Carbohydrates on average store 3-4g water for every gram of glycogen stored.  So a large reduction in carbohydrates means a large amount of stored muscle glycogen is used without being replenished on the first couple weeks of a low carb diet.  And along with that?  Lots of water weight.

Sure, you can reduce your carbohydrates to 50g per day (and eat 150g of fat a day) and still lose WEIGHT.  But it doesn't mean it is fat.

Is it all a lie?

There is, in fact, a lot more detail we could go into here but the above highlights how a simple reduction or change in "X" doesn't necessarily mean you've found the Holy Grail of dieting. But because of user bias, a reduction in weight from water the first 1-2 weeks of a keto diet might convince you that it works way better than a moderate carb, moderate fat diet.

If weight loss is occuring, as in true weight loss from fat, it's because you're in a calorie deficit.

Please remember this as you begin any nutrition journey this year promising better results because of "X".  If it's actually working, it's because you controlled calories.  Remember that real, pure weight loss from fat is slower than we'd like to think. 1/2 to 1% bodyweight reduction per week is pretty much as good as it gets if you are consistently in a calorie surplus.  Water weight changes skew this and also either appeal or frighten our ego, often eading us to make emotional decisions.

You can lose fat and retain water at the same time.  In fact, expect it at some point in a calorie deficit - stress from work, calorie reduction, exercise, lack of sleep and much more can cause more chronic rises in cortisol leading to water retention.  All while losing body fat.  The best thing you can do in this case in stay consistent on your nutrition and make lifestyle changes to address the stress.

Sometimes, it is that simple

You know how I said it isn't that simple?  Well, to quote Charlie from It's Always Sunny In Philadelphia, "it is and it isn't".

We like guarantees.  This is one of the reasons people will stay at a just OK job for years because of the benefits and promise of solid retirement.  If we know we are guaranteed an outcome, we'll do things that we don't really like or love.  I might love sweet potatoes, rice and fruit but if cutting them out guarantees me a shredded and muscular body, I'll do it.  And if I am going to invest that much in cutting out a whole food group, you can bet I am going to defend it as well.  An attack on my personal nutrition is an attack on me. This is the state dieters take on.  We become emotionally invested in an approach because it makes us feel good or safe and criticism or even helpful advice can often feel like a personal attack.

if someone has had success with a nutritional approach?  Look out, because that means, as the Mandalorian would say, "this is the way".

Emotional investment plus personal bias?  That's a tough nut to crack. Telling someone that their low carb diet worked because:

  • it created a consistent calorie deficit and
  • was something they could sustain

as the primary reason for their success really throws a wrench into the gears of finding that "one thing", 

Funny thing is, reducing calories overall usually leads to a reduction in carbohydrates and fat anyway.  Fewer calories means less room for carbohydrates which means a reduction in their intake along with a reduction in insulin. Losing body fat from a combination of fat/carbohydrate reduction will improve insulin sensitivity, leptin sensitivity and improve a host of health markers.  If you're eating 1800 calories a day to lean out, you don't have a lot of room for carboydrates anyway, it's not like your intake could even be that high on a calorie-controlled plan. This might be a tough pill to swallow but high fat diets also cause insulin resistance.  Ketogenic diets cause insulin resistance.  If your carbohydrates are chronically low it doesn't matter that much but you can become insulin resistant from consistently overeating fat (specifically saturated fat), not carbs.

Lowering calories overall, eating an optimal amount of protein and doing that consistently yields most of the results.  Not to pick on low carb or keto because they can be effective nutrition strategies for some but often not for the reasons we think.  Same could be said of intermittent fasting, carb/calorie cycling, clean eating or any other nutrition approach that doesn't specifically talk about calorie control.

Just remember, if fat loss stalls or fat loss occurs, it's due to your energy balance.  You can manipulate this through multiple means but it's always going to come back to your total calories eaten (in general). 

Before ditching your current plan or trying something extreme, consider that your probably just need a small, measured calorie change which can be  from a variety of means.  Just know your success isn't relegated to just "one thing" and you always have options for how you adjust your nutrition.