What are calories?

What are calories?

Defining the definition of calorie isn't difficult: according to the majority of science textbooks, this is simply the quantity of energy needed for raising one gram water by 1-degree Celsius. But how does that relate and relate to caloriecounts we see all over everything from menus for fast food to nutrition labels on snack bars

If we take a look at caloriecounts when we look at caloriecounts, we're typically trying to figure out how much energy we're putting to our bodies. But a nutrition label cannot be able to provide that, at a minimum, precisely. There are too many variables to consider, many of which are dependent on the physiology of an individual, as well as others of which we're still trying to figure out.

Consider this: Starting in the year 2020 the almonds suddenly looked like they had around 30 percent less calories than they did the year before. Cashews and walnuts went through the same decline in the energy content. The nuts themselves did not change, of course, but the method employed to calculate calories changed.

It's because those who work for the FDA and USDA frequently still use the same method used for centuries to measure calories. originating in the late 19th century (though the exceptions are made in cases where there's more current research available, for instance, for the nuts). In the latter half of the 20th century Wilbur Atwater, a scientist from the late 19th century decided that it was time to assess the amount of energy in foods by burning the food and calculating how much energy it contained, then feeding the same food to the people and analyzing how much energy is contained in their poop and pee. The distinction between energy in and energy out, in a sense has become the calorie-calculating numbers that we employ for macronutrients in the present: nine calories in one gram of fat, and four each in one gram of carbohydrate or protein.

In the 19th century this was an enormous leap forward in our understanding of the energy density in food. However, for the 21st century the results don't match up.

[Related The truth about counting calories[Related: The truth about counting calories

An calorie of fat in a walnut, for instance, doesn't appear to mean the exact as the calorie of animal fat. Though it's still unclear the reason for this the implication is that our bodies don't digest all food products in the same way, meaning that certain calories remain within the food and exit in our poop. They haven't impacted our waistlines at all. (We need to note that the research on calories-in-nuts was partially funded by different board members, although the parties involved didn't create or perform the studies themselves).

This concept of bioavailability has been a relatively recent topic of research, therefore there's not a lot of information regarding other types of food items we're ill-informed about measuring. For instance, we're aware cooking food tends to make the nutrients contained in it more available. We are also aware that our individual microbes living in our intestines help determine how much energy we extract from our food, like by breaking down cell walls in certain vegetables. The Atwater system does not account at any point for cooking food and even less, the way you cook it, and it doesn't take into account different bioavailability levels between different types of food. It's all about the amount of fat, protein, or carbohydrate in the food.

The new studies on nuts don't utilize a more advanced method as Atwater employed. The researchers gave almonds (or cashews or walnuts) to the participants and examined their poop to determine how much energy was absorption. It's not that the USDA scientists took the time to study one food in particular.

Until we find a better method of quantifying the amount of energy contained in each food category and the term calorie is, in reality is a term we've assigned somewhat arbitrarily to food. Try not to think about it too much.