Calorie Deficit and Sleep

In_the_bank

I've been doing a calorie deficit diet (500 calorie deficit) for a month with regular exercise and things seemed to be going smoothly as I would work out around 5-6 times a week rotating through different focus areas and was able to lose 10 pounds.

This month however hasn't gone the same way. I haven't been able to go to the gym at all in about a week as I will fall asleep right after work and wake up a few hours before my usual bedtime ruining my workout schedule. This is completely unplanned and kind of concerning. Is it possible I need to up my caloric intake? It was working before without these side effects but now I'm wondering why this changed so quickly. I will be honest though and say I didn't eat the best the last two days.

ahoy_m8

Losing 10 pounds in a month suggests an average daily deficit over 1100 calories net after exercise. That’s an aggressive rate of loss (appropriate for folks with 100 pounds to lose). You don’t say how much you have to lose, but an excessive deficit will cause fatigue because you just need more fuel.

Consider losing at a slower rate, e.g. 0.5lb/week if your goal is losing 20 lbs or less.

AnnPT77

Ten pounds of loss in a month suggests that your deficit is not 500, but more like 1100 (i.e., (10/31)*3500). Results tell you more than any so-called calorie calculator can.

If you are well over 250 pounds currently, and have 60-70+ pounds to lose, that might be theoretically OK, but could still be excessive if you have an otherwise high-stress life. (Calorie deficit is a stressor, big deficit (fast loss) is a big stressor; new exercise or increased-intensity exercise is a stressor; stress is cumulative across all sources, physical and psychological . . . and excessive total stress is a bad thing, even if some of the stresses are net positive things, longer term.)

Fatigue is a bad sign - one of those "canary in the coal mine" things. Worse can happen - much worse - if weight loss is too extreme.

I'd suggest dialing back to get an actual weight loss in the 0.5% to 1% of current weight per week range, with a bias toward the lower end of that, and definitely that 0.5% if your total stress is high. (0.5% would be about a pound a week at 200 pounds current weight, for example.)

I think you're seeing this show up "suddenly" because a body will try to soldier on through excess stress for a while . . . but it catches up to you eventually. Eating in a lower-nutrition way for a couple of days would add a tiny bit more stress, but isn't likely to be the whole story.

TL;DR: Yeah, eat more. Keep a bit of a challenge in the ongoing exercise load, but don't kill yourself there with punitive, intense, exhausting exercise all the time, either. It's not ideal for either weight loss or fitness improvement.

sijomial

" Is it possible I need to up my caloric intake? "
Yes!
Your weight loss is out of line with what you think your actual deficit is.
Maybe you picked the wrong activity level, maybe you haven't been accounting for your exercise calories, maybe you simply diverge significantly from average.

" It was working before without these side effects but now I'm wondering why this changed so quickly. "
Because humans can tolerate an excessive deficit for a short period of time before their bodies try to compensate by slowing you down to reduce your calorie expenditure.

cwolfman13

A 500 calorie deficit would be 4 Lbs lost in a month...you're more than double that. Yes, large calorie deficits will result in fatigue because calories are energy.

JBanx256

You're running a HYOUGE calorie deficit right now so some serious fatigue is to be expected. Personally, my recommendation would be to take a diet break (eat at maintenance) for a solid week, and see if that doesn't help your energy levels. I'd throw in a couple/few rest days (preferably a couple consecutive, just to give your body time to really recover). When you return to a deficit, make it a significantly smaller one, so you're not right back in the same boat.

In_the_bank

Thank you all, I’m so glad I asked this. I was at an insane deficit as I forgot to include exercise in the calculation and also only have 15 pounds left to lose so that rate was definitely not sustainable, healthy and I probably also lost a little muscle. I’m taking it a lot slower and been eating around maintenance (with more protein) and have felt a lot better and been able to go back to working out. Oh and lost a pound this week without the sluggishness. Thank you all again as this feels a lot healthier!