How accurate is the weight goal tracker in cronometer?

blessenparker

When I tell it I want to loose 0.5lbs per week. And it adds in the calorie deficit to my cronometer. How accurate will this be for my weight loss. Is it different for everyone or is it somewhat accurate? I'm wanting to loose weight over a period of 2 to 3 years. I don't want to loose it fast to avoid the chance of excessive skin or stretch marks. I'm about 50-70lbs overweight.

TheRegents

It's different for everyone because the basal metabolic rate (BMR) calculation and your physical activity level -- which together cronometer uses to estimate your daily energy expenditure (excluding extra intentional exercise that you should log) -- is an estimation based on population averages for your gender, age, height, etc. That's not to say that the estimation is always wildly inaccurate though and on average it's pretty good for most people. It's certainly good enough for assisting you to lose weight at a certain rate. (From memory, it can be out by about +/-300kcal for most women but if you read below you'll see that for weight management this doesn't matter at all).

Bear in mind, though, that you may need to tweak how much you eat (calories) because everything is an estimate and based on averages. If you're consistent with your logging this tweaking can also have the effect of cancelling out any inaccuracies; i.e. if you're inaccurate then it doesn't matter so much as long as you're consistently inaccurate By tweaking what I mean is that if after a suitable period of time (maybe 4 weeks) you're losing weight too quickly then increase your intake slightly until you reach the rate of weight loss that's right for you. Similarly if you're not losing weight as quickly as you expected then decrease what you're eating slightly. By doing this the inherent inaccuracy of BMR and physical activity estimates doesn't really matter because you can negate that inaccuracy by controlling what you eat (or how much you exercise, etc).

As for how cronometer determines how much weight you'll lose if you're eating at a deficit of x calories, well I don't know the exact formula they use but that's an estimate as well. It's based on how many calories are in y kilograms (or whatever the appropriate unit is) of body fat, also factoring in that the weight of human body fat includes somewhere around 24% water. Again, it's accurate enough for weight management.

Susan_RD_101

@blessenparker

One pound of weight is the energy equivalent of 3500 calories. Thus, if we divide 3500 calories by 7, we get 500. So theoretically, if you are reducing your maintenance calorie target by 500 per day, you will lose on average 1 lb of body weight per week. BUT, your metabolism will ultimately decide how quickly you lose weight.... When people cut their calories too drastically (i.e. eating 800-1200 calories per day, on average) and as a result, lose large amounts of body weight, their metabolism goes into panic mode (since your body thinks you are sick or starving) and slows down drastically. This slowing of your metabolism leads to a weight plateau.

When it comes to weight loss, slow and steady does win the race so great job for having such a smart approach to it. I also just want to mention that it's hard to know if you will have excessive skin or not. The rate of weight loss doesn't necessarily determine excess skin as much as total weight loss does.

Lastly, only weigh yourself 1x per week max and look at the month-to-month changes. Bowel movements, hydration status, menstruation (for women), can all mask weight loss on the scale.

Best of luck on your journey!

sulohna

how do we determine our activity level

Hilary

@sulohna you can change your activity level in the profile tab of Cronometer. To learn more, see: https://cronometer.com/help/profile/#vitals