Is a Calorie Just a Calorie

The Answer:

Yes, and no

If you have a lot of weight to lose, then yes, a calorie is a calorie, it doesn't matter what type of food that calorie comes from.  From a health perspective you just need to get that weight off.  So a sensible eating plan (ie no fad diets like just eating grapeful ,or one meal a day or anything that is not nutritionally sound) monitored using a program like My Fitness Pal, or the Calorie King, regular exercise and a resultant calorie deficit or between 500 = 1000 calories  (ie more calories burned per day than consumed) is pretty much all you need to worry about.  Eat what you need to and when you need to, to be able to stick to the calorie plan, because the health risks of obesity far outweigh any fine tuning that I'm going to talk about below.

However, if you're not so far from a goal weight eg in the overweight or the lower end of the obese scale perhaps, then let me tell you that not all calories are the same.

You will benefit from understanding about Macronutrients and Micronutrients, and about the timing of when you eat.

Macronutrients

All food can be broken down into a type of Macronutrient: Fat, Protein or Carbohydrate,
Every gram of these macronutrients has a different calorie value

Fat -     1 gm = 9 calories
Foods like butter, cream, oil are pure fat, its also found in most foods but high in  nuts, avocado,  and then lower but significant amounts in meat and animal products, dairy

Protein 1 gm = 4 calories
Most pure forms in Whey and Egg whites, and high in meats fish  and dairy

Carb     1 bm = 4 calories
Vegetables, fruit, grains (like oats, wheat etc=bread, dry biscuits) sugar

So you can see that if you choose to consume 10 grams of fat (eg oil) you are eating 90 calories, versus 10 grams of protein (say egg white) you are eating 40 calories.  So same quantity of food, but one is much more calorie dense (the fat) than the other.  On a basic calories in/calories out scale, eating foods that are less calorie dense (eg protein and carbs) allows you to eat a greater quantity for the same amount of calories. 

That's pretty easy to visualise - just compare one of those snack size potato chip packs (supposedly good for school lunches) 100 cals, versus a plate heaped with vegetables worth a 100 calories.

But the point about macronutrients is not about calories, its about what they do for your body.

Protein is used to maintain and rebuild muscles. Of interest after eating it you only have about 3-4 hours to use it.  You can't store it for long periods of time.  So having all your protein in the evening meal is a waste and what is not used will be converted to fat.

Carboydrates provide you with the fuel for exercise in terms of blood sugar levels. Once again, what's not used is converted to fat for storage.  You will have heard about Low GI foods - these are the ones that provide a slow release of sugar into the blood stream, which is preferable to high GI foods (like chocolate bars, but also items like potatos) that give it to you fast.  They all have a differing impact on insulin levels and the way your body stores and handles fat.

Fats - provide essential nutrients to the body that can't be produced internally.  And I know you would have heard about good fats and bad fats. and the truth is some fat is essential.

ANY excess food consumption that can't be used will be stored as fat, but you can help your body out by giving it the right type of nutrients at the right time

Eg

•  Carbohydrates before exercise,
•  Protein and/or a mix of Carbs/Protein after exercise
• A steady stream of protein throughout the day rather than one big hit
• Keeping complex carbohydrates (bread, pasta etc) to a minimum in the latter parts of the day when they are less likely to be used to fuel activity (the exception to this is if you exercise in the evening)
• Avoiding high GI foods (especially refined sugar) which spike insulin levels and reduce fat metabolism

Learning what you are putting in your body and when, (on top of "how much") is the key to changing the composition of your body.  Remember the photos of people at the same weight but looking a different size? A higher body fat at the same weight as some one else results in a bigger looking, flabbier body.  A body builder weighs a lot but has very little fat.  The body chooses to retain and build muscle, and drop fat - when we feed it with the right macronutrients at the right time to achieve this.

Micronutrients are what nutritional value a food has for normal bodily functions.  So if I said to eat carbohydrates before exercise and you could choose a chocolate bar, versus and yoghurt and some fruit, you can guess that the chocolate bar would be a poor choice as it offers very little nutritionally.  If there are a limited number of calories that we should eat each day - we should be choosing a variety of foods from all of the food groups to ensure we get all of the vitamins and minerals that we need.  Eg are you getting enough fibre, Vitamin C, magnesium etc.  If you are on a very low calorie diet (eg 1200 cals/day) it can be difficult to get a full range, so it is worthwhile taking a multivitamin to be sure.

Thats a very brief summary - but I will refer you to this great book by Coach Calorie - that explains it in more detail The Definitive Guide to Lose Weight. Its an excellent guide to macronutrients and more.