Help working out my calorie deficit? - Weight Loss NHS

Weight Loss NHS
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Help working out my calorie deficit?

CrimsonMama6 stone

The NHS BMI calculator says my daily calories should be 1636 to 2037. That's after I put that I am active.

So... If I was burning 500 calories a day with exercise is that already taken into account with the NHS equation? Because my aim is to cut 500 calories in diet and burn 500 in exercise to create a 1000 a day deficit for a 2lb a week weight loss.

Without exercise the lower end it gives me is 1401. Which is only 235 difference? So it's allowing the rest to come from the exercise? Is that right? Or the 235 is to "power" the exercise so my deficit of 500 exercise is minus the extra 235 it allows me to eat?

I'm getting confused! (And btw my exercise according to mapmyfitness is about 700 a day give or take). And I consume the equivalent of 1500 a day. So far I have been losing 2lb a week with occasional 1 lb and occasionally 3lb.....

11 Replies

Oh dear :( I'm always thrown by these complicated sums :(

Yes, the NHS BMI calculator does take your level of activity into account. When I was calorie counting, I always just followed the NHS BMI calculator and stayed in the upper half of my range. It was something like yours when I started and I went for around 1800+. It worked for me.

I now have a low carb high fat approach so I don't count calories, or anything else.

Don't get tangled up with numbers, just work on eating well. As a wise person here said, "Eating shouldn't require a postgraduate degree".

There's a very good post on the LCHF forum on the same point. You'd need to follow that forum to read it but you can then unfollow, if you want

Happy_lady2 stone

I think you posted something similar the other week. The NHS guide already takes into account calories used to exercise, hence it asked you your activity level, and gives the calories needed to safely loose weight if your BMI is too high.

If you choose to eat 500 fewer calories then your loose may be slower. It does seem odd, but too few calories may hinder your weight loss.

mazza364 stone

Hi CrimsonMama - my understanding is that the calculation of calories and exercise done is not linear so you can't merely subtract one from the other. On the internet there are loads of articles about myths surrounding statements like 'you need to burn an extra 500 calories a day to lose 1 pound per week'. My opinion is that as you exercise more over time your body becomes more efficient at doing the exercise and probably eventually it loses its effectiveness, so you change the exercise as much as you can (or increase it). Lowering the calorie intake won't work as your metabolic rate decreases when your body goes into starvation mode, which is probably why the BMI calculator doesn't align with the increase in exercise. Hope this makes sense? Just before Christmas I really upped my exercise and reduced my calories. To my frustration I lost no weight. Over Christmas I relaxed my regime a little and last 2 pounds. You have to work on your metabolic rate if you do a lot of exercise.

CrimsonMama6 stone in reply to mazza36

Ah very helpful thank you. I like the idea of eating more calories not less lol but it's very very hard to get over the idea that more must be bad! So far whatever I'm doing is working but I get thrown off if nothing budges one week (silly I know) and one of my coping mechanisms is to go back to the drawing board and crunch the numbers and schedules!

I guessed the 3500 deficit = 1lb weight loss thing can't be entirely accurate as sometimes I lose 3lbs (a 10,500 deficit? No way). But I saw an interesting article on here about the whoosh effect (fat cells turn to and hold water then whoosh when it goes is a bigger loss). However there are still so many articles out there that do not mention this and stick to the strict calorie in calorie out formula.

lismclRestart Jan 2020 in reply to mazza36

I also find that the more exercise I do at higher intensity, the less weight I lose too, no matter what I am eating. It feels quite counterintuitive, but as my primary goal is fitness, I'm not too sad about it.

mazza364 stone in reply to lismcl

Lismcl - I read recently that HiiT loses more calories than spending a long time exercising but they both burn fat at the same rate. I have translated this to mean that HiiT is more efficient. I don't mind time spent exercising as I use it as a bit of a stress buster. Now started cycling regime so will see how that affects my weight.

CrimsonMama6 stone in reply to mazza36

I get frustrated when I see that cycling for 40 mins is like half the burn of a 40 mins walk/jog. But it's still good to have the variety. On weekends my youngest likes to ride with me and although that means I have to go slow we are usually out far longer than if I'm riding full out and in that way burns more calories.

I've been reading recently that a longer work out at less intensity actually targets burning fat more whereas a high intensity for shorter time does burn calories more efficiently but burns less fat as your body uses its stores of - is it glucose? - first before fat stores. Less intensity means you are less tired and go for longer so you get into the fat burning stage.... Does that make sense?

Lol I only read all this stuff to keep me motivated with my exercise! Who knows how much of anything we read is true! I guess so long as the weight -and fat - is going that's the main thing!

mazza364 stone in reply to CrimsonMama

Agreed! We get so much conflicting advice, in the end I do my own thing and chill out while exercising. I hate the HiiT thing as I feel kind of bullied into it (that sounds pathetic). Let's face it, any exercise is better than none and if it helps with weight loss - brucy bonus 😄

mazza364 stone

CrimsonMama - I panic when I don't lose weight! I am panicking big style this week as I have been out for a couple of meals. Since I started my healthy lifestyle I must admit I've only gained a couple of odd weeks so something must be working.

CrimsonMama6 stone in reply to mazza36

I was pleased when I only put on 5lbs over Xmas and New Year. I was prepared to gain like 7-10lbs! I was still exercising even though I let the diet slip so that must of helped! Usually having the odd higher calorie day doesn't matter too much on the scale.

When I visit my mum she always wants to go out to Subway or a cafe for a bite! It's very frustrating as I don't want the extra calories! But last time I had a tea cake and hot chocolate which wasn't too bad. I even used sweetner instead of sugar in my drink!

Don't forget that your body uses up calories just living - heart beating, lungs breathing, blood pumping. It all takes energy. Think of exercise as an additional way of burning off a few calories. Don't take the exercise readings as gospel. Also, according to your figures you are not consuming enough calories according to the NHS guidelines. Bodies are funny things. If you don't eat enough, the pre-history neanderthal brain kicks in and thinks there is a famine and will withhold burning off fat and you lose less weight. I know this from experience as well. If I eat a little bit more sometimes, I have a better weightloss. You are using guidelines for exercise, so don't forget to use the guidelines for how many calories to eat. Good luck.

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