I got to thinking about what are some of the common beliefs that sabotage your weight loss efforts. So I thought I'd discuss a few:
1. You must balance calories in and calories out. This is a biggie and is the hardest one to debate but let me try. First off, and easiest, this belief makes people think they just need to eat less than they expend to lose weight but there is a problem. How do you know how much you expend? Sure, there are calculators out there on the web that will tell you but those are based on statistical models and generalizations. You are how old, how tall, how active... boom you burn this much. But how do you know with any level of certainty. Also, if you eat less, ie. take in less calories, your body can react with slowing down metabolism. So that at one rate of intake, say 2800 calories a day, your body may be burning 2200 calories a day. BUT, if you drop your intake down to 2200 calories, your body may respond by slowing down to 1700 calories a day. You can chase this number all you want.
Anecdotally, I once went on a diet where I was eating 1000 calories a day and exercising. I ended up plateauing for a few weeks and broke it by INCREASING my intake by 500 calories a day. So you don't really know what you are expending so it really is quite pointless to say you are trying to balance this.
Now, I'm a low carber, so my views on calories in - calories out is a bit different from 'normal' people. I do believe there is some value in knowing what you are taking in (both in terms of calories as well as macro nutrient amounts) but mostly from the standpoint of seeing how your body reacts to that. If your body loses weight at 2000 calories a day with 20 g of carbs but stays weight stable at 2800 calories a day and 100 g of carbs, that's a good thing to know. It's also important to note your energy levels as low energy levels could be the result of your body overcompensating for a lack of available energy.
2. Exercise will help you lose weight - I started some blog posts as a result of this question. Exercise will not significantly affect weight loss. Why? Because you expend incrementally not much energy and it will result in your body wanting more energy intake. For example, if I run on the treadmill for a half hour, I burn about 250 calories. But if I just sat down for that half hour, I'd probably burn about 75 or so calories. So my net result is about 175 extra calories burned. However, if as a result of that I feel hungry, I will most likely eat up that 175 calories (it's not hard).
I am not saying don't exercise, I'm just saying that don't expect it to result in weight loss. There are benefits. Resistance training can help with muscle insulin sensitivity (at least I've heard it can). It can help with mood. it can change your body composition. It can have other health benefits. But killing yourself in the gym will not make you lose significant amounts of weight.
To those who say 'I know a guy who went to the gym 6 days a week an hour and a half a day and got slim', I'd ask, what else did he do? Did he change his diet? Did he quit smoking? Most likely, he did so we really don't know what caused weight loss.
3. Becoming fat is a result of lack of will power - To this I say, read my 'Let's make Grok Fat' post. Grok 'overate', not because he couldn't resist that donut, but because his body was telling him he needed more energy and he listened. I've been obese. I was close to 300 pounds. The drive to eat appears to be emotional and psychological and yes there is some of that element, but the hormonal aspect is much stronger and contributes much more to the equation. Hormones will affect behavior. If you've been around a pregnant lady who is going through cravings or hormonal changes, you probably have noticed this. I may get comments about that last sentence calling me a chauvinist but I've known women who have gone through pregnancy and they talk about it too.
If I think of more I'll do a part two to this post. That's all I have for now.