I'm sure many active dieters have noticed how their body weight can, at times, drastically fluctuate without much rhyme or reason. Perhaps some of you have had a big feast one day, yet noticed weight loss the next? Or maybe you've dieted extra hard, only to see some weight gain the following day?

All in all there is little reason to worry. There are many things that might change our body weight and what's most important – changes in body weight do not mean changes in fat or muscle mass. Noticeable changes in those areas take time, more than a few days for sure.

So what is going on? Let's bring out a few potential suspects that can cause weight fluctuations.

1. Water weight.

Our body is mostly water so we can reason that even a tiny change in water levels can bring about considerable weight change. But what can be the cause?

Sodium. Consuming more salt than usual can cause water retention. If we consume a lot of pre-packaged and pre-seasoned products for example, we increase the chances of getting more than the usual amount of sodium. That isn't much of a danger by itself, but in such a situation, your body will need more water to compensate for the added sodium. That means you may start drinking more liquids without even noticing it. You may wake up the next morning and find yourself bloated, as if your body has suddenly gained a couple of pounds, your waistline may have increased and muscle definition gone down.

Still – there is little reason to worry, it is temporary and your physique is still pretty much the same as it was before. If you keep the diet consistent, your body will adjust the water and sodium balance.

Carbohydrates. This often goes hand in hand with the previous point. Once the ingested carbohydrates have been digested and the initial energy requirements are met, the rest is stored as glycogen in our cells. Glycogen, however, binds with water. This means that consuming more than the usual amount of carbohydrates, can lead to additional water gain. Now if we put both the sodium and carb intake together, we can understand why high-carb, high-sodium fast food binges can make us feel like we've gained several pounds of fat overnight and look horrible to boot.

The reverse is also true however. Cutting down sodium and carb intake can quickly flush water out of the system, resulting in weight loss..

2. Food mass.

Digestive processes can take a considerable amount of time. Often it can take days before all the food waste is expelled from the body. That means that the food you eat at a big feast can remain in your system for a while - skewing weight results. Though the reverse can also happen – digestion can be fast in some cases, resulting in rapid clearance of the bowels. It depends on the types of food, fiber content, water intake and more.

What all this means, is that inconsistent nutritional habits, especially those which contain a large variety of food sources (and thus many possible sodium and carb intake variations) can lead to irregular, short term fluctuations in body weight. In truth it is nothing but an illusion that does not reflect the actual changes in fat or muscle mass. It does however make it feel as if some foods are making you lose fat and others gain it.

Still, such fluctuations can disrupt the effectiveness of the diet. Simply because measuring progress and making corrections in the nutritional plan can be difficult with the weight constantly in flux.

Does all this sound familiar? I'm sure some of you have tried diets that make you lose several pounds very quickly, inches of the waistline and more. And yet all of it comes back the moment you stop the diet.

Now you know why. In many cases such diets are nothing more than these same manipulations in water weight and food mass that we brought out above. Selling such dieting plans is a big business in the modern world – there is never a shortage of people looking to get into shape real fast. Because the people looking for such rapid fat loss methods often have low self esteem, they tend to blame themselves when the diet ultimately fails. They were unaware that the diet was never going to succeed in the long term anyway, no matter how diligently they followed it.

Throw away such diets that promise rapid fat loss in the scale of several pounds in a few days. Such short term illusions are not worth the risk to your health.

I hope that in the future you will be able to gauge the importance of your body weight a little bit better. I'm sure some of you will be a bit disheartened to hear that the few pounds lost since yesterday may not mean much – but I'm sure you will all be much happier over solid long term results instead.

Happy dieting!