I know, I know; I'm like a broken record at the moment and I have written more posts on this exact topic over the past few years than I can even keep track of.
Good though, sometimes you need hear things a few times before they really sink in. Especially when it's different to what you're used to hearing.
IIFYM = "if it fits your macros".
An approach to sports nutrition about calculating and then planning to meet your requirements for energy, protein, carbohydrate & dietary fats. Treat fibre as an additional macro too in my opinion.
I reiterate and emphasise this point: it is SUPPOSED TO BE about calculating your ACTUAL requirements. When people just say "if you're in deficit you'll see results in fat loss" or whatever, all that infers is that you're not exceeding your requirements. It doesn't suggest that you're getting what you need. In most cases it's just some arbitrary level of restricting on the basis that it can't possibly be enough, therefore tough it out, be accountable, distract yourself from hunger, etc.
Seeing fat loss DOES mean you are in deficit but not seeing fat loss DOES NOT necessarily mean that you are not in deficit, and the solution to a plateau or stall in progress is not necessarily to slash intake further into deficit.
Here's the thing, just as an example:
At let's say 700 calories per day into deficit, progress stalls.
For one of my clients who comes to me in this circumstance, I'd actually do some maths, predict what level of energy intake I'd expect to produce best results, and work with the client on a strategy to increase towards that amount.
I don't do maths based on "calculating a deficit" but for argument's sake let's say we're going to increase until we're only 150 calories per day in deficit.
Higher TEF, RMR & NEAT no longer compromised, resources actually available to recover & benefit from training. We will see better results.
Others argue "if you're in deficit you see fat loss and if you're not seeing fat loss you're not in deficit" and therefore the approach is just "whatever you're doing now, subtract a few hundred calories and that's your new target". That's garbage. Enforced anorexia is all that it is.
The issue in most cases that I see isn't that "you're no longer in deficit" but rather "you're too far into deficit and have been so for far too long". Over restricting. Excessive levels of restriction, and often excessive & unproductive levels of expenditure.
Now, I had a stupid idiot argue the other day that (paraphrasing) "if you're not seeing fat loss then you ARE at maintenance and NOT in deficit", but if we can facilitate fat loss at a HIGHER intake... then the LOWER amount that had ceased to result in fat loss due to compromised NEAT & RMR is clearly also in deficit.
Now... it's simple and correct enough to just say "you require enough, but not too much" or "you require a deficit, but an appropriate level of deficit and not an excessive level of deficit". You require that resources such as carbohydrate & protein are available to produce improvements in condition as an adaptation and benefit from training.
To me that is simple enough but it seems to be too complex for most of these chumps to grasp with their primitive intellect and myopic application. Being in deficit does NOT guarantee results, and slashing further and further into deficit recklessly and indefinitely is a dead end. LITERALLY.
Want more? See also: Ending The Unhealthy Obsession With Calorie Deficits