Debunking dieting myths

I do completely recognise the irony of the director of a plus size underwear retailer writing a hub on losing weight, but as someone who has been vastly overweight, underweight and everywhere in between, who has read so much on the subject, tried various diets and routines, taken up exercise, given it up, started again, told myself every lie under the sun... you get the picture.

What drives me crazy though is reading blogs, or hubs even, spouting complete nonsense about weight loss. I don't just mean the crazy "lose 14lbs in 17 days" stuff - honestly, if you're gullible enough to believe your body can shift that sort of weight in such a short time, I lose hope for humanity. But just in case, think about this:

1. It took you years to put the weight on. It's not going to come off again in a few days.
2. 7lbs of fat is roughly 24,500 kcal. Even if your body required 3,000 kcal per day and you starved yourself for a week, you wouldn't use up that amount of fat.

Erm, hang on, I'd better just qualify my qualifying statement:

1. You'd need to be either very overweight or very active to have a requirement of 3,000 kcal per day. Women tend to need around 2,000 and men tend to require around 2,500. This varies depending on age (your metabolism slows and you require less as you grow older - yes, that sucks), your weight (even fat requires calories for your body to service it, so being heavier requires more calories) and how much you exercise (doing things burns energy, or calories, so do more and burn more). There is an excellent calorie requirement calculator here on About.com. Bear in mind 1lb of fat is equal to 3,500 kcal and you have all the figures you need to calculate how to lose weight.
2. Don't starve yourself for 7 days. It's a terrible way to lose weight. Your body will go for the easiest places to get calories from and long term fat stores aren't it, muscle and protein are, so you'll actually be reducing muscle mass, so reducing your ability to burn calories daily. That's before the significant health risks.

Onto the main event then, things that drive me round the bend:

1. Counting calories doesn't help you lose weight / Calories are a bad way of calculating food.
   Calories are not the only way of working out the value of food. There's glycaemic indices and all sorts of other things. But unless you are pro athlete, and for most of us that are simply overweight, calories are the most effective way of staying on top of your diet. It's really simple maths. If you eat less calories than your body requires to function (and you can boost that through regular exercise), then you will lose weight.
   
   Yes, there's more to it than that, but not for most of us. For 99.9999999999% (my scientifically proven number ;-) ) calorie counting works. But only if you don't cheat. Track your calories accurately and don't lie.
2. It matters where you get your calories from.
   This is one I wish were true, but isn't. A calorie is a calorie. Your body breaks it down and uses it. There's plenty of studies of people eating nothing but potatoes (carbs) and losing weight. However, it does matter what you eat if you want to be healthy. If you decide to lose weight by eating an all Mars bar diet, you can do it if you stick to the calories, but you're an idiot. If you want to lose weight, it's because you want to be healthy, and eating healthily matters because your body needs different things.
   
   Again, there's no rocket science here. Don't eat too many fats (look at the food labels), eat lots of vegetables, a reasonable amount of fruit (not too much, as they contain lots of sugar) and lean protein (beans, chicken, turkey, lean meat, fish, etc). There's a great food pyramid hub here.
3. Eating after 8pm / 10pm makes you gain weight.
   There's no evidence that eating later or at any different time of the day makes a difference to weight. The exception is breakfast, which everyone agrees kicks you metabolism off so you start burning more calories earlier. (Healthy breakfast is suggested to be protein based - eggs, ham, etc - rather than the traditional carbs - cereal.)
   
   What is shown by studies is that people who eat when they are tired, ie later, tend to eat more carbs, so in other words, if you eat later you're more likely to eat food that has more calories. As ever, it's the total calories that matter not what or when.
4. Drinking cold water makes you lose weight.
   I wish. Again, tonnes of studies on this. Technically it's true. If you drink a fluid that is below body temperature, your body has to use up some of its energy (calories, remember) to bring it up to temperature. But it's a tiny amount. Not enough to provide any benefit.
   
   However, it is true that quite often what you perceive to be hunger is actually your body being thirsty. So if you feel hungry at a time when you don't think you should, have a big glass of water, wait 20 minutes and then see if you are actually hungry.
5. Going to the gym makes you put on weight.
   It's self evident this one, isn't it? Anyone who says exercise isn't good for you is crazy (barring genuine medical reasons). What isn't going to help you lose weight is walking sedately on the treadmill for 20 minutes while chatting on the phone, then going to the gym cafe for a huge latte and cake while telling your mates that you've "been in the gym". Exercise is difficult. If you're not sweating at the end, you're not doing enough.
   
   Most people who say that they actually put on weight when they went to the gym did so because they used the excuse of the gym to overeat their calorie allowance. End of.

There are more, I could go on, but what dieting myths drive you crazy? Let us know.