The terms "kcal" and "calories" are often used interchangeably in nutrition, but technically they refer to different units of measurement:
Calorie (small "c"): This is the scientific unit that represents the amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius. It's a very small unit.
Kilocalorie (kcal): This equals 1,000 calories (small "c"). It's the amount of energy needed to raise the temperature of 1 kilogram of water by 1 degree Celsius.
The key point: When you see "Calories" (with a capital "C") on food labels or in nutrition discussions, these are actually kilocalories. So when a food package says it contains 200 Calories, it technically contains 200 kilocalories or 200,000 small calories.
In practical terms:
This is why you might see food labels that say either "200 Cal" or "200 kcal" - they mean exactly the same thing. The confusion arises because different countries and contexts use different conventions, but nutritionally speaking, they're equivalent measurements of energy content in food.
At EMW, I try to use Cal or Calories as that's what most people are familiar with from food packaging in Canada (or the USA).