When the summer comes, thousands of people decide to lose some weight, before jump into swimsuits. Unfortunately, most of them go into their crash diets with misconceptions of what a diet should be, and end up worse off than they were before.

When most people make the decision to lose weight, their first step is to cut back on the amount of food they eat.

Mistake Number One:
You have no idea how many calories you are currently eating or how many calories you should be taking in to reach your weight loss goals.

Next, a dieter might decide to throw in some daily cardio exercise like biking or running, because that's what everyone else does.

Mistake Number Two:
While exercise will help you burn fat, it's important to remember that the kind of exercise you do, such as cardio or resistance training, and the amount of time you do it, will affect how your body responds. The right combination of cardio and resistance training combined with the right diet will jumpstart the weight loss process.

After cutting back on their food intake and running every morning, our dieter loses a couple pounds the first week. A couple of days go by without any weight loss, so the dieter cuts their food down even more. Their energy drops, and running is making them more tired than usual. They might lose a little more weight, but their food cravings are worse, and they're getting cranky.

As a last ditch effort, they cut their food intake down again and increases their running distance. Now it seems like they're always tired and hungry. Their mood is terrible, and even though they've lost ten pounds, when they look in the mirror, they don't look any different. If fact, they probably look worse.

Finally disgusted, they quit their diet. They figure if they need to kill themselves for an ideal body, it probably isn't worth it.

The Number One Reason why diets fail is most people have unrealistic expectations of how long a true body-changing diet should take. Popular culture has fed this misconception by supplying a constant barrage of "Lose 10 Pounds in 10 Days" crash diets, which only dehydrate you and shed valuable muscle, not fat.

Here's an interesting fact: a pound of fat takes up five times as much space as a pound of muscle. Since crash diets shed muscle instead of fat, our dieter hasn't changed their overall shape!

Every time you go on a crash diet you are going to lose muscle until your body adjusts itself to getting fewer calories. But the chances are that by the time your body has made this delicate adjustment you’ll have given up on the diet, so when you start eating normally again your body is overwhelmed with the extra food and starts slapping it straight back on as fat. Your metabolism – the rate at which your body burns those calories – can remain lower than usual for weeks after you finish your diet. Your body remembers how much fat you used to have and wants to put it back quickly in case you suddenly start dieting again. Which, of course, many people usually do.

Think of your body as a fireplace; the fire is your metabolism and the logs are the food. If you disappear for the day and leave the fire unattended, the chances are that when you come back to it in the evening it will almost be out. You might stoke it up with logs to get it going again, but the embers won’t be hot enough to get them burning. When you look at the fireplace the next morning, you might find your logs from the night before are still lying there, a little charred, perhaps, but not burnt up. If you have a habit of going for long periods without food, your metabolism will slow right down. Perhaps you’re working hard so you skip lunch, finish work late and stop for pizza on the way home. By that time, of course, you’ll be feeling pretty hungry – but don’t be fooled: Your metabolism will have virtually given up by then. Eating a big meal and going straight to bed means you’ve got less chance of digesting that food quickly and burning it up. It’s much more likely to be turned into fat and stored. If you eat small amounts regularly, you will have a better chance of using it up as you go along.

In a healthy weight loss program, a dieter should expect to lose about two pounds of body fat every week (a woman would lose about one and a half pounds). Five pounds of fat takes up the same volume as a loaf of bread, so losing ten to twenty pounds of fat will make an enormous difference in your appearance, especially compared to losing the same amount of water and muscle weight.

It may be slower than a "Lose 10 Pounds in 10 Days" crash diet, but the harsh reality is a year of yo-yoing on fad diets will likely leave you heavier than when you started and making the same resolution next year. The same time spent on a healthy weight loss program could leave you 50-100 pounds lighter next year.

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