Trying to reconcile weight loss with calorie deficit

Joe64321

I just finished my 2nd week of using MyFitnessPal. My goal is to lose 15-20 pounds, with a target weight loss of one pound per week - although my hope is to lose the weight much faster than this. I already have a good workout routine (3x60 min HIIT sessions + 2x30 min cardio sessions per week), but I added to it a 4-6 mile walk per day in hopes of speeding up my weight loss. I have very carefully logged everything I am eating, and have run a 17K calorie deficit for my first two week. This has so far only translated into losing 3.2 pounds, which while great, is not what I would have expected given the combination of increased activity and calorie deficit. I'm just wondering if anyone has any insight into what might be going on here. If I burn substantially more calories than I have targeted, shouldn't I be losing weight much quicker? Is there something I am not accounting for? Or is the calorie computation just not something I should be relying on?

Lietchi

Your weight is much more than your fat mass. Most notably: food waste in your GI tract and, most of all, water weight also influence your weight on the scale. Increased exercise, for example, can cause water retention.
A difference if 2lbs between what you expected and what you see on the scale is wel within normal weight fluctuations

I recommend:
- using a weight trend app like Libra or Happyscale to see your weight trend beyond the fluctuations
- being patient - 4 weeks at least (or 1 full menstrual cycle, if applicable) to have enough data for a true evaluation
(and better to use your weight trend number (average over the last x days) rather than single weigh-ins to calculate your true TDEE and deficit)

tomcustombuilder

You have to be patient with losing. Look at things in a month. Unless you’re very overweight that deficit is too big and there is always the possibility that you’re undercounting calories. See your loss in 4 weeks and do the math on the size of what your actual deficit has been.

Say you lose 7 lbs in a month that's a monthly deficit of 24,500 calories now divide that by 30 and that gives you a daily average deficit of 816 calories. If youre weekly activity level and exercising program is fairly consistent then you can go to a moreTDEE type of equation where you don't figure in individual exercises

Lietchi

PS: calories in and calories out seem like a simple equation. But it's like trying to hit a moving target.
For example, you added walks to your routine to increase calories burned but:
- Being aggressive with your deficit can cause your metabolism to slow slightly (subtle things like slower nail and hair growth,...) partially compensating for the walk
- being aggressive with your deficit and/ or increasing exercise can make you more tired and less active in daily life (this can be subtle too, for example less fidgeting or moving around) partially compensating for the walk

Retroguy2000

Your deficit is determined by your weight loss over time, not by online calculators and exercise estimates. Ignore the first week, which likely has more water weight loss.

As Lietchi said, use a daily average of weight tracking.

Regardless what MFP says, if you burn 500 calories doing HIIT, which may be 420 calories more than had you done nothing instead, you can't assume those 420 calories are available to eat or are automatically part of your caloric deficit. That isn't how the body works. You might only get half those calories as deficit, and that's assuming the original 500 estimate was correct too. The body tends to reduce NEAT to compensate for intense exercise.

What was your weight loss in pounds in week 2? That multiplied by 500 is your daily deficit. Moving more won't help much, since you're already doing so much. You'll need to reduce your CI if you want to lose faster.

Corina1143

17000÷3500=4.857 lbs expected loss
For ME--your statistics will differ
No longer bathroom trip today=weight up .2 to 2 lbs tomorrow.
Large meal close to bedtime=up .2 to 4 lbs tomorrow
Dehydrated = down .2 to 2 pounds
Took a shower, washed my hair, it's still wet = up 5 pounds
Exercised more than usual yesterday = up 2 to 4 pounds
Cut calories sharply + exercise at least 2X usual for several days or weeks. Initial water loss of 2 pounds, then body revolts. No loss, just swelling, soreness, etc.

Of course I'm large (not as large as I used to be) and old = 74.
But I'm close to goal weight, too, and it just gets slower and slower.

AnnPT77

Reinforcing what others have said: Once you have 4-6 weeks of personal experience data, that tells you what your actual calorie deficit is . . . as close as you're going to get anyway. Anything MFP, another calorie calculator, or even a fitness tracker tells you is just a starting estimate based on statistical averages for demographically similar people. You're an individual.

Anything shorter than 4-6 weeks (whole menstrual cycles for women of relevant age/stage) is likely to be distorted by shifts in water retention, and variation in food waste in the digestive tract on its way to the toilet sometime within the next 2-3 days.

If I may be frank, I'm troubled by something: Your post feels like you're thinking fast weight loss is better weight loss. I have a strong bias that that's not true. IMO, the best weight loss is sustainable weight loss, and learning/practicing enjoyable (at least tolerable/practical) new habits that get us to goal weight, yes . . . but more importantly, keep us there long term, ideally forever.

Many people think maintaining is harder than losing, but maintaining IMO is the big prize.

On top of that, a moderate weight loss rate we can stick with can get us to goal weight in less calendar time than an extreme, punitive, restrictive routine that eventually results in deprivation-triggered over-eating, breaks in the action, or even giving up altogether.

That's in addition to the utterly correct points made above that high exercise load can result in counter-productive fatigue (so less movement in daily life, less net calorie burn than expected); that fast loss increases health risks; and that fast loss effectively trains our bodies to limp along on fewer calories long term because they can't tell an extreme diet from a famine they should adapt to get us through alive (not a path to thriving good health).

Give it a think. I'd suggest opting for sustainability (permanent habits) and training for robust thriving . . . but it's your call.

Even as a total stranger, I want you to succeed long term, because reaching and staying at a healthy weight has been such a huge quality of life improvement for me. I want that for everyone.

Best wishes, sincerely - no matter what you decide.