Harish Palaniappan's

What's is a Calorie?
Simply an unit of energy.. while energy itself is imaginary by nature, its measurements are also based on studies and are only approximates.

That means, there's no truth in someone saying "this has 23.21 calories".

Technically, 1 Calorie is the amount of energy required to raise temperature of 1 KiloGram of water by 1 °C (sometimes defined as 1 gm of water rather than 1Kg.. then its called a small calorie with small 'c' in calorie.. big calories are what we are talking in this article).

Also, it is not correct to say that a sandwitch with cheese has so much calories because energy acquired by the body through foods most often is also dependent on the person eating. Haven't you known people who eat good, and burn up less calories, but still are slimmer than you.

First burn.. The myth:

> Myth: Calorie ratings in foods, and workouts..are exact.

Calorie ratings in food labels and items are only indicatory and approximate.

Does it mean.. all those labels on food containers are wrong?? No. But they are crude approximations. These ratings should only be used to help you understand which of two foods is higher in energy or Calories, so you can decide. Only for referrence. Also the same with your workout machine's calorie reading in your health gym.

History of the link between calories, diet and workouts.
People made observations under lab conditions that fats have so much calories, carbohydrates have so much etc., and the food manufacturers add up the calories based on the ingredients they have used in the food, and put it on the labels.

The same way, personal trainers calculated per hour calorie burn-ups in certain workouts based on how much people reduced in weight doing the workout for a month. And the numbers were set into the machines you workout on..finally giving you a number of calories you burned by exercising on them for 30 mins or so.

This later got mixed up with dieticians making cocktails of calorie charts custom made for people of certain ages, in a crude and approximate way, and all this became standards of measurement in diets and workouts...which never had any measuring standards before.

You should only consider the Calorie rating on things as approximations of energy levels.. as said earlier, to compare foods or to compare workouts. That's how dieticians / your gym trainers actually understand it, though some of them mistakenly put it to us as the exact number.

> Myth: Eating less food, means less calories and is good for being in shape.

As stated earlier, Calories are measurements of Energy.

And Energy is required for being active or doing work, so avoiding food intake itself heavily, is going to bother your health and lifestyle itself if you don't understand it correctly.

Take salads at times, avoid high intake of fats at times, etc., but keep a healthy mix.

Everyone's body is different, and the way it reacts to food or workout is also different (though its debateable, medically physiology is a unique aspect of birth and growth).

So, over a period of time, you will find a mix of food intake and schedules which best fits your energy requirements based on your activity levels at different times in the day, and based on your craving for certain foods.

Don't starve your body with a calorie rule book...starve it with giving importance to energy rather than satisfying crave.

> Myth: More Calories, more weight.

This is a misconception. Weight and calories are totally unrelated.

Still this misconception is popular because some people take a lot of food, sometimes 3-5 times their energy requirements... the higher unused energy becomes stored fat (discussed later).

If you don't link your food intake with respect to your lifestyle or activity then you will either be under-nourished or over-weight.

> Myth: More energy requirements means ..more physical activity.

Many many people believe that doing physical activity is the only good reason for higher energy requirements. In my opinion this is not true.

The brain needs energy too..though it is smart to use less energy to do more work. Keep yourself starving for long, you would have a head-ache. Also, for what other reason do you think the brain sometimes makes us feel stressed or sleepy. Why else should caffeine or tea be able to strengthen our focus at work, sometimes over long work hours.

Yes. it means, doing nothing also consumes energy.. but if you are trying to understand, may be sleeping all the time, without nightmares, with low activity in the brain, could reduce energy requirements.. and keep you alive longer without starving to death.

Something like above should answer how an old woman in her 70's survived for close to 14 days under the debris of the Gujarat earthquake in India in 2005(if i am right) without food.

What is meant by "Burning up"?
Physical exercise increases activity and hence energy requirements, and if you still eat based on your old energy requirements, you will be starving your body of some energy, which it has to makeup by burning up the stored fat in your body.

This is when you are typically "burning up" and losing weight.

Hence, when you use more energy than you intake through food, you are losing weight. When you use almost the same amount of energy that you intake, you are maintaining your weight.

How to lose weight.. why it takes time.. why shouldn't you use electrodes and other non-exercise stuff to reduce weight quickly.
Related to the above discussion on stored fats.. we have to understand that, every human being more or less has the same amount of skin and body tissues depending on their age and growth... the rest is all made up of stored fat.

Stored fat is mostly what makes people fat or heavy...and is stored in bulks under the skin. And, why is it stored when you don't want to? When your body needs more energy the stored fat is burnt up and converted to energy needed.

This is a more complex process involving metabolism, breakup of food or fat into acids and molecules, etc., but we are reading this very crudely to keep it simple.

That complexity is what will help to understand why then all the fat can be burned up by simply not taking food.

But, to look at it easier, to break-up stored fats also needs energy which comes through food intake. Food intake, we already know that if it is in excess, it still add up to the stored fat.. So this creates the balanced limit to amount of fat that can be broken up over a period. This is why losing weight is a long-term process by nature.

And since going against nature always has implications, people advice you to not force the break-up of fats through means other than exercising...and even through exercise, only to a limit to avoid over-stress in workouts which could cause other problems.

Why Junk foods are always criticized:

No intentions of hurting anybody when they criticize everything to junk food intake. But everything said is truth.

There's a big difference between junk foods and foods. While people eat normal foods for energy requirements, junk foods are had for satisfying that crave. Also, junk foods are manufactured with no nutritious or low-calorie intentions(and hence called 'junk'), they are just prepared for giving that crave or satisfying that crave.

This means that junk foods are usually high sources of fat, carbohydrates, oils and milk products. Your dietician would obviously scream hearing you had all that in your food.

Junk foods are inevitably the quick and easy sources of food given today's predominant lifestyles...and its difficult to close doors on them. But help yourself by being careful to avoid them, by eating low, and drinking juices or water whenever you get the crave.

References:
http://en.wikipedia.org/wiki/Calorie
http://health.howstuffworks.com/calorie.htm