Without getting too esoteric about what affects calories in, calories out, calories absorbed, margin of error allowed in reporting of foods by the USDA or how we’re not combustion engines; it is generally accepted that to lose 1lb of fat an energy deficit of approximately 3500 calories is required.
For the purpose of this post I’m going to use MY maintenance calories; yours may be a lot higher or a lot lower. My maintenance is approximately 2500cals/day and my goal is to lose 10lbs so I eat 1850cals/day to create a 650 calorie daily deficit.
Here’s how that breaks down using my numbers:
Weekly calories to maintain my weight 2500 x 7 = 17500
Weekly calories based on my planned deficit 1850 x 7 = 12950
Estimated fat loss per week: 1.3lbs
Time required to lose 10lbs: 8 weeks
It’s Thursday evening; there’s Nutella and peanut butter in the cupboard and I’m craving something sweet, fat, and chocolaty. I wait the 10 minutes I told myself I’d wait but I still have a burning desire to kill the jars with a soup spoon. I probably don’t have to tell you what happens next; I ate a lot of Nutella; even more peanut butter; had some creamed honey, and washed it down with 2 big glasses of milk. It was delicious but now I’ve had 3500 calories instead of the 1850 calories I planned I would have once I add my unplanned eating to the food I’ve already eaten.
This next part is important so pay attention because it separates the people that reach their goals from the people who don’t.
I have 3 options:
Option 1: I’ve ‘ruined’ my day. I’m not going to put this in my food diary because ‘I don’t want to know.’ Tomorrow is Friday and there’s always treats at the office. I have 2 muffins for breakfast; I have pizza for lunch; I have a bottle of wine after work; repeat similar on Saturday and Sunday and start fresh on Monday. It *is* the weekend right?
Outcome of option 1: I’ve had 1850cals Monday through Thursday and Friday through Sunday I have 3500 each day. My weekly calories end up being 17900. That’s slightly over my maintenance calories for the week; I’ve gained 0.1lbs of fat this week (which is still a ridiculously small amount) and I’m probably beating myself up mentally. That’s assuming I kept going to the gym on my schedule to keep my maintenance at 2500; which if I’m honest, is pretty unlikely if I’m eating like I’m on death row.
Option 2: I can’t do anything right, why did I let myself eat all that food? I need to make this up somehow. I’m fasting most of the day tomorrow and I’m only going to have chicken, vegetables and rice. I might try and do some extra cardio and try and burn some of this off. I am NOT going to eat any more than 1000 calories following my dietary transgression.
Outcome of option 2: Monday through Thursday you’ve had 1850 calories, Friday you had 3500, Saturday you had 1000, but Sunday you were so hungry because of the very low calories and extra cardio that you end up having another day like Friday, only this time you keep going and you eat every-single-thing you’re never going to have again because you need to get back on track so your Sunday was 5000 calories. You’ve had 16900 weekly calories ending in a similar scenario as the option above; but you’ve still lost 0.1lbs of fat.
Option 3: I really enjoyed what I wanted to have and even though it wasn’t part of my plan sometimes things don’t go according to plan; nobody is perfect. Let me log all this food and see the damage I’ve done. It was 3500 calories; that is a lot. Thank goodness I’ve been adhering to my calorie budget up until now; I haven’t really set myself back very much and that was super tasty! Tomorrow I’ll hit the gym as usual and I’ll get back to my regular routine of 1850 calories/day.
Outcome of option 3: I’ve had 1850 calories every day of the week with the exception of Wednesday when I had 3500. My weekly calories now total 14600 and I still have an energy deficit of 2900 calories. Instead of losing 1.3lbs this week; I’ve lost 0.8lbs.
For a fun exercise multiply the consequences of each decision by multiple weeks.
10 weeks x option 1 would be about 0.8lbs gained
10 weeks x option 2 would be about 1lbs lost
10 weeks x option 3 would be about 8lbs lost
Where would you rather be?