Calorie Calculator

What are calories?

Defining what constitutes a calorie seems simple: According to the majority of textbooks in science, this is simply the quantity of energy required to raise one gram liquid by 1 degree Celsius. But how does it relate and relate to caloriecounts that are displayed everywhere from fast food menus to the nutrition labels of snack bars

When we think about caloriecounts, we're typically trying to figure out how much energy we're pouring to our bodies. However, a label on a food item will never be able to provide this, at the very least, exactly. There are too many aspects to consider, many of which depend on the individual's physical condition, and other factors that we're still working out.

Think about this: In the year 2020 nuts suddenly appeared to have about 30% less calories than they had in the year before. Nuts and cashews both experienced a similar drop of energy density. The nuts themselves did not change, however, the method employed to calculate calories did.

That's because the FDA and USDA typically still use a century-old method for measuring calories. The method was first developed in the late 19th century (though there are exceptions if there's more current research available, like for these nuts). In the late nineteenth century Wilbur Atwater, a scientist from the late 19th century decided that it was time to gauge the amount of energy in food items by burning the food in order to determine how much energy was inside it and feeding the same food to people and measuring the amount of energy that was present in their poop and pee. The distinction between energy that was in and the energy that went out, in a sense was the basis for the calorie-calculating figures that we currently use for macronutrients nine calories in one gram of fat, and four in grams of carbohydrate, and protein.

For the 19th century this was a huge leap forward in the understanding of energy density of food. However, in the 21st century, it doesn't quite add up.

[Related: The truth about the counting of calories]

It's true that a calorie of fat in a nut, for instance, doesn't appear like the same thing as the calorie in animal fat. While it's unclear the reason for this and why, it's likely that our bodies aren't able to breakdown all food items equally, so some calories remain inside the food, and then go into our poop. They haven't had any effect on our waistlines. (We must note that the research on calories-in-nuts was partially funded by various nut boards, though those who were involved in the research didn't actually design or conduct the research themselves).

Bioavailability is been a relatively recent topic of study, and there's not a lot of information on other kinds of food products we're not measuring. We've learned, for example that cooking food can seem to make the nutrients contained in the food more readily available. We also know that our personal microbes living in our intestines help determine how much energy we extract from our food and this is done by breaking down the cell walls in certain vegetables. The Atwater system doesn't take into account any point for cooking food or even how you cook it, neither does it take into account differing bioavailability of different types of food items. It's just based on how many grams of fat, protein, or carbohydrate is present in the food.

The new nut research doesn't even employ a more advanced method than Atwater utilized. The basic idea is that the researchers gave almonds (or cashews, walnuts or even cashews) to participants, and they measured their poop for the amount of energy absorption. It's just that the USDA researchers wanted to study one food specifically.

until we can find a better way to measure the energy within a specific food group, it is believed that a calorie, really is just a number we've given to food items. Try not to take it too seriously.