too much fat loss?

[dude111115]

Hi, In the past few weeks i've been pretty busy working a new job with 12 hour shifts. I rarely eat anymore, just yesterday I only consumed 600 calories but yesterday through this morning I burned around 4000. I've been losing weight drastically, and in addition to that, in the past week my body fat percentage has gone down 6%, from 22% to 16. Is this too much weight loss too fast? Could it affect me negatively in any way? I've read before that losing more than 2 pounds per week can be bad for you but I haven't heard much in the way of body fat percentage changing. 

In the past week, I've gained 10 pounds of lean mass, and lost 3 pounds overall (I've lost about 12-13 pounds of fat)

Any information would be appreciated, thanks. 

[carl669]

how are you measuring fat percentage?  a scale?  my guess is that you haven't actually lost 6% in the past week.  i'd chalk it up to variances (hydration level, general inaccuracy, full moon etc.) in the scale you're using.

[josephz2va]

It depends on both your Diet and your Exercising. How willing you are to push your limits to get there.

True. Losing more than 2 pounds per week can be dangerous, but that's regular mass. They haven't mentioned fat mass unless you end up being below the threshold of 8%.

I've shredded 5% in one week from concentrating on my diet and aggressive exercising. Double timing my gym attendance to hit up to 90 minutes maximum cardio of 130-147 BPM (my trainer's pushing me to do 148-160 BPM now) and performing isolated muscular exercising.

[dude111115]

I've kept myself rather hydrated, and I doubt it has to do with variances
in the scale. Every day i've lost nearly 1%. I could accept that the scale
might be innacurate overall, but I doubt a scale would be innacurate in
measuring a change. Either way there has been a rather noticeable physical
change; everywhere except my stomach my muscles are now clearly visible
through the skin, although on my stomach I can't see much, because I've
lost 50 pounds this past year and I have a lot of loose skin there...
Anyways I average between 10,000 and 15,000 steps a day on top of standing
for 12 hours strait 3-4 days a week at my warehouse job.
I'd like to point out, carl669, that your answer was not helpful by
questioning the accuracy of how I was measuring. Assume I'm measuring
correctly and provide a realistic answer to the original question.

[Snowflakepdx]

You have burned off all the glycogen in your muscles.  The scale doesn't know the difference between stored glycogen and stored fat.  Many endurance athletes can store 6 or more pounds of glycogen and water in their muscles that can easily be burned off in a cardio session.    Some of what you are burning is fat.  Some of the nutrients in your blood are breaking down.

The impact of not eating and resting while exercising is a over time it causes stress and burns out your adrenal glands trying to coax your body to stay in motion.  once they are gone it takes months or year to recover.  I will limit any kind of fitness growth.  Most people get injured trying to fight it so they don't recognize it.     It is called overtraining and this is why professional athletes work with coaches.   Get yourself on a nutrition plan

[Heybales]

Oh, those scales are at best 5% accurate, and that's if you present an exactly hydrated the same body to it.

Some scales are more accurate (like 5%), but inconsistent, so you'd bounce around in that 5%.

Some scales are more consistent than accurate (like 10%), so always on the same side of inaccuracy. Those at least indicate a direction over a long period of time.

If the day prior was a workout day, then invalid weigh-in and use of the BF function, as exercise messes with hydration level beyond what you can control. Well, except for waiting it out.

You ever gotten off the scale, turned it off, back on, and tested again?

Because indeed, sometimes answering the question is indeed a matter of pointing out it's an invalid question based on incorrect assumptions.

"Daddy, why is the sky green?" "Son, it looks green to you?" "Sure" "We need to see a Dr, I can't answer your question."

Great results though, but you should be concerned, because the accuracy isn't that great, and unless you are doing some strength training, with that huge deficit, you are losing the average 20% muscle mass along with whatever fat you are truly losing. I don't trust your scale for a second. DEXA scan yes.

[Tracy577]

I have no advice or fancy reasons for why I think you lost all that weight so quickly...I just simply wanted to express my jealousy. Haha!

[TheSageMage]

FWIW, I've heard that drastic weight loss like this can cause loose skin. You mentioned gaining lean mass though so it may not be a problem, just wanted to pass on the wisdom I've heard.