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What makes a food “healthy” and how do we choose at the store?

Photo of Lucy Sparrow’s 2017 art installation at the Standard: an all-felt bodega. Technically high in fiber…


TL;DR: “Healthy” foods feed us something we need: essential nutrients our bodies can’t make, the fuel we need to move, and the experience of food are all things to consider when we choose which foods to eat. (about 9 min read)

Steps for deciding between different packaged foods:

-       Protein & Fiber first. Simple carbs in proportion to the amount of movement you normally do.

-       “Hard to find” vitamins and minerals second.

-       Nutritious, delicious, nourishing: Food is also an experience, enjoy it.


 “Healthy” foods are foods that feed us something we need. And we need to do two things: to make new cells when we’re growing or healing, and to move around. Healthy foods supply the nutrients to do this.

There are “essential” nutrients that we can only get from our diet: amino acids and fats (yes, there are fats you NEED to get from your diet such as omega-3 and omega-6 fatty acids and a low-fat diet may not provide enough of them), vitamins and minerals. Carbohydrates are not essential; we can make carbohydrates in our own body.

Our diets also supply “Food as Fuel”. Food provides that fuel that we break down the things to make non-essential amino acids, fats, and carbohydrates. The things we make in our own bodies are called “non-essential” because it isn’t essential that we eat them in our diet. We make these molecules so that we can make new cells (for healing, for new blood cells, for new gut cells, etc, as well as growing bigger muscles).

Another way we use “food as fuel” is to fuel our movement. Even though we can make carbohydrates and maintain steady blood glucose levels (BGLs) without eating any glucose, sometimes we use glucose faster than we can make it (like when we’re doing a lot of aerobic exercise. If you gu, you knew.) When we use glucose faster than we can make it, then getting some from our diet helps us move faster and not be limited by our pace of production.

Prepared and packaged foods are convenient and will probably always make up some part of your diet. Maybe you’re someone who always has time to food prep, gets all their produce from a local garden, and is never caught out in the wild without snacks in stacks. But most of us aren’t.

There is a lot of marketing on packaged foods to convince us they are healthy. What do we actually want to look for? We want to start with the nutrition label and get protein and fiber first.

The Nutrition Label is a lot more informative than the ingredients list. The ingredients list gives us a good idea of how processed a food is and, well, what the ingredients are. If some type of sugar (including dextrose, honey, agave nectar, cane syrup, coconut sugar, corn syrup, maple syrup, or another “natural”* sugar) or refined flour is listed in the first three ingredients, this food is going to have a lot of simple carbohydrates that spike our blood glucose levels (BGLs). Eating foods with refined flour or sugar in the first three ingredients when we aren’t going to be moving around, or when there is a lot of insulin in our system (like before bed) will create metabolic imbalance (aka stress) that leads to storing more glucose as fat.

The rest of the ingredients list will give us an idea of how many preservatives are in a food, or if there is a non-sugar substitute. Non-sugar substitutes fall into a couple of categories; we want to avoid the ones that raise our blood glucose levels (saccharin and sucralose)* and the sugar alcohols (xylitol, sorbitol, and mannitol).

Side note: Sugar alcohols are not absorbed by our guts; that’s why they don’t raise our BGLs. However, not being able to absorb something across our guts also causes bloating and GI distress.

Look at the protein and fiber content first. Then, take a look at the total carbohydrates. Added sugars and sugar alcohols will be listed under total carbs where fiber is also listed. We want to avoid foods with a lot of added sugars and sugar alcohols. Ideally, we’d also choose foods with low total carbs as well. What is “low” total carbs is going to vary by person – someone eating a ketogenic diet may sacrifice fiber in a packaged food in exchange for a really low carb count. Someone doing a lot of endurance activities or trying to build muscle mass may pick a food with a higher fiber content that also has a higher total carb count. If you aren’t sure what is a “high” or “low” amount of carbs for your lifestyle right now, check out this guide or talk to a coach.

If two foods are relatively similar in protein and fiber/carb content, look at the vitamins and minerals. Some vitamins and minerals are easier to get in our diets than others. For example, vitamin C is in a lot of fruits and vegetables and most people are not at risk of developing a vitamin C deficiency. Iron is in heme groups (so red meats, beets) and some whole grains and nuts (chia seeds are a great source of iron). It’s a lot harder to get iron from common fruits or veggies and a lot of people are anemic at some point in their lives*. If you’re choosing between two foods with relatively similar protein & fiber, go with the one that has more of the “hard to find” nutrients. Again, which nutrients are “hard to find” is going to vary by person, so if you aren’t sure which nutrients you currently get in your diet and which ones you need more of, talk to a coach.

You don’t have to worry about fat content if you focus on adequate protein and fiber. Your digestive system has sensors that tell you when you have eaten protein, fat, and fiber (but not sugar, this is why sugars don’t make you feel full). You need a certain amount of fat for your brain to register that you’re full. If you focus on protein and fiber first, you’ll feel full and be taking in nutrient-dense foods. You won’t have to worry about fat. (Go ahead and try it out for two weeks with a food long if you’re skeptical).

There are no “bad” foods. Remember that everything you eat should feed you. If you are eating something that isn’t feeding you that many nutrients, ask yourself what part of you it is feeding (Core memory: making cinnamon rolls with my great grandmother. Not high in fiber. Also not going to skip eating them). It’s okay to eat things that aren’t “super nutritious” but they should be super delicious. Don’t eat foods that don’t feed you. Enjoy what you’re eating and how it makes you feel.

Steps for deciding between different packaged foods:

-       Protein & Fiber first. Simple carbs in proportion to the amount of movement you normally do.

-       “Hard to find” vitamins and minerals second.

-       Nutritious, delicious, nourishing: Food is also an experience, enjoy it.


*The quote marks are not to say that the sugar isn’t natural, they are a reminder that natural does not automatically mean something is good for us. Cyanide is natural and found in apple seeds. It’s also a poison.

*Fun fact: long-distance running increases our need for iron because we break a lot of blood vessels in our feet from just striking the ground for so long! It’s called “foot strike hemolysis”. Hemo = blood; lysis = breaking a cell open. The more blood cells we lose, the more iron we need to replace them. This is one of the reasons why beets are good for long-distance performance.  

* Suez et al. (2022) Personalized microbiome-drive effects of non-nutritive sweeteners on human glucose tolerance. Cell.