The NPB Mailbag: How Do I Track Meals and Macros?
When it comes to measuring what you consume, you're better off keeping it simple.
Realtime request: finding a quick, easy method for tracking meals and macros. So many apps, so little time to meticulously manage that sort of data. What's the solution?
- Austin
Thanks for the question, Austin! The short answer is that most trackers are based on the same databases—and that data is an estimate, at best. With that in mind, pick a tracker with bells and whistles that appeal to you, but don’t use it to micromanage your eating, because the information it’s giving you isn’t that accurate anyway. Instead, use it to look for larger trends in your diet.
In other words, there’s no need to be meticulous.
Now, pour yourself a cup of your stimulant de choix and take a comfy seat. Here comes the long answer.
Our knowledge of the calorie is olde timey.
Calories and all the wonderful arithmetic that has blossomed out of them—including macronutrient ratios, calorie calculations, and nutrition information panels—have their uses, but only as rough estimates.
This is a tough notion for most people to wrap their head around. Calories are practically an American institution. Everyone knows what a calorie is, at least in a roundabout sort of way, but do you really know what a calorie is?
Calories are a unit of measure for heat. Similar to the way a car converts gasoline to energy, our bodies convert food to energy. Heat is a form of energy, thus calories are a way we can measure the energy that food produces.
As a reminder, if we don’t use the potential energy in food, it’s converted to body fat to be converted to energy at a later date.
If we examine the math that tracks how our metabolism converts food to energy, we see there’s a lot of averaging and guessing involved. For example, we say there are four calories in a gram of carbohydrates, four calories in a gram of protein, and nine calories in a gram of fat. These measurements were established by a chemist named Wilbur Olin Atwater in the late 1800s. He was completely transparent about the fact that those numbers are averages. Within the different forms of carbs, fat, and protein, the numbers vary quite a bit. But that’s been brushed over, so the Atwater system remains the USDA’s go-to calculation, despite being kind of vague.
The USDA’s food tracking data is a hot mess.
USDA FoodData Central is widely considered the gold standard for tracking calories, macronutrients (protein, carbs, fat), and other nutrients. To my knowledge, most meal tracking apps primarily use this database for the information they provide.
According to a recent review of nutrient databases in the journal Advances in Nutrition, “despite important contributions from the USDA and others, food and nutrient databases in their current forms do not yet provide truly comprehensive food composition data.”
But you don’t need a scientific journal to learn this. Instead, go to FoodData Central, search “avocado,” and hit the “SR Legacy Foods” tab. Here’s what you get:
Provided you know the difference between a California and a Florida avocado, there’s still that “all commercial varieties” curveball that’s based 86 percent on California avocados and 14 percent on Florida avocados. All three of these entries have different nutrition information.
(For the record, Florida avocados are the big, smooth ones that stay green when ripe. California avocados, aka Hass, are the smaller ones with nubby skin that turn black.)
Hit the “Survey Foods (FNDDS)” and this happens.
Two more avocados—and why do sandwich avocados get special treatment? And how do they know how many tomatoes I put in my guac? They’re not the jefe of me!
I’m not saying the USDA intel is wrong. All of these results give you a roughly correct avocado breakdown. But if everything you log is roughly correct, the sum will also be roughly correct.
The inaccuracy of nutrition facts labels.
What’s more, the FDA regulates accuracy in nutrition facts labels—and they allow a 20 percent margin of error. To make that crystal clear, the calorie information on a packaged good can be up to 20 percent wrong and it’s still all good, man. In case you don’t feel like perusing the 14,000-word FDA opus I linked to above, here’s the exact wording:
“(T)he label is considered to be out of compliance if the nutrient content of a composite of the product is greater than 20% above the value declared on the label.”
So, even if the USDA were completely on-point, the information provided to them for their database would still be off when it comes to packaged goods.
The proper role of food tracking apps.
Despite working with all this wonky data, trackers can play a useful role. They promote accountability and they generally show you what you’re consuming. The trick is not to get all locked into the numbers. If you’re trying to eat 30 percent protein, 40 percent carbs, and 30 percent fat (based on calories), don’t worry about being spot on. You’ll lose your mind—and you’ll still be off, even if the tracker says you’re perfect.
Either way, your body isn’t math-based. You don’t require exact numbers to thrive.
Instead of getting lost in daily details, look for overall trends. Track other aspects of your life along with food, including athletic performance, mood, poop, and sleep. Look for connections. For example, if you have several solid training sessions in a row, could it be that you’re eating something for breakfast that’s working for you? Or maybe you’ve been really on-point with post-training protein?
Over time, you'll start to notice patterns—what works for you and what doesn't.
Which tracker to choose.
As I said, reputable trackers are mostly based on the same data, so just pick the one with an interface that speaks to you and go for it.
If you follow a specific meal/diet program and they offer a branded tracking app, it’s probably just as solid as other trackers out there. If your tracker provides meal plans that help you choose the foods that work for you, all the better!
Or, if your employer or insurance company offers free access to meal tracking, you might as well take them up on it.
A lot of apps let you track by snapping photos of your food. This dials up the speed and convenience, but adds another layer of estimation.
If you’re old school, you can always take pen to paper and start a food journal. You can eyeball your macros. If you need some help with that, there’s always, ahem, USDA FoodData Central.
Between innovations in data aggregation, technology, and personalized nutrition, it’s a matter of time before someone figures out a better way to accurately track food. But even when that happens, it needs to be paired with the most reliable app for helping you understand what’s best for your body—and that’s the app between your ears.
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