When and What to Eat
To say there are conflicting messages about the when and what to eat is an understatement. As a licensed dietitian that specializes in eating disorder recovery, I’ve seen what can happen when these recommendations lead people down paths they never intended to travel. I’m going to share my evidence-based guidelines with you about when and what to eat, along with a little of the science behind them.
Disclaimer: if these recommendations conflict with what your medical providers have advised in light of a condition you’re managing, check with them before applying these suggestions.
When to eat: Every 2-4 Hours
This recommendations is based primarily on the brain, the liver, and blood sugar for prominent their role in the demand and production of glucose. Please note this will likely mean you will have a few snacks throughout the day, which is encouraged!
THE TLDR: the brain demands a constant supply of glucose, which is stored in the liver. Between meals, we break down that storage to feed the brain. When we go long periods without eating, our body will adjust by reducing our metabolism, aka; our overall energy demand. Eating every 2-4 hours keeps us from depleting liver energy storage and preserves high-energy tissues such as muscle and skin repair.
THE BRAIN: of all the energy a person uses in a day, the brain accounts for 20% of it. The brain also never turns off, meaning it needs a constant source of energy. It also has a Blood-Brain Barrier, which only allows certain substrates in the blood to enter the brain. This means that the brain is particular about what it eats. Only two things get through the Blood-Brain Barrier to nourish the brain: glucose (otherwise known as blood sugar) and ketones (the by-product of fat metabolism).
BLOOD SUGAR: many people associate blood sugar with diabetes where there’s a concern about spiking blood sugar. While diabetes is a condition wherein the body struggles to absorb glucose into cells and therefore, blood sugar spikes can cascade into other issues, an increase in blood sugar after a snack or meal is a natural consequence of eating that bodies are generally prepared to accommodate. Our bodies will either use the glucose it needs for energy-resysnthesis (scientifically called, ATP turn-over) or our bodies will store glucose for a later time in the form of glycogen or adipose tissue (fat) respectively. And that’s where the liver comes in…
THE LIVER: storing unused energy as fat in the form of adipose tissue was an incredible evolutionary advantage we developed. It’s what allows us to be as mobile as we are and gives us our resilience against famine. That said, storing our energy in adipose tissue is like storing our non-perishable, emergency food items in a box in the attic; it’s not easy to get to, not preferred for daily use, and is intended for dire situations. Luckily, our bodies also have bookshelves and cupboards that are more easily accessible in the form of glycogen.
Glycogen is stored in two places, muscles and the liver. Glycogen in the muscles is preferred during exercise and the storage capacity can change with training. Glycogen in the liver has a more static capacity and the rate of use depends on our overall metabolism; aka, the overall energy demands on our body. When we don’t eat for a long period of time, our metabolism will adapt to the lack of resource and reduce the demand on our energy needs. This is when a metabolism slows down to prioritize our brain’s constant demand for nourishment. It does this by reducing muscle tissue (protein is an incredible high-energy tissue to maintain), slowing digestion, and reducing hair and nail growth.
Oftentimes a suppressed metabolism is blamed on a person’s weight and the mainstream recommendation is to shift their energy balance to a deficit, meaning they use more energy than they consume. The nutritional biochemistry suggests that this would actually exacerbate the problem, which also explains why 95% of intentional weight loss efforts don’t last beyond the first year.
Generally speaking, it’s safe to estimate that eating 2-4 hours helps stay ahead of depletion and reassures your body that there is enough resources not only meet energy demands, but even build tissues that require more. If a metabolism has reduced in effort to accomodate low-eneryg environment, resuming consistent nourishment is an important step in bringing the metabolism back up to speak. The symptoms of supressed metabolism named earlier will often resume normal function.
To use our food-storage analogy, grocery shopping consistently (eating every 2-4 hours) reassures those in the house (or heart, intestines, and hair/nails/skin) that they cannot only eat when they’re hungry but they can create elaborate and delicious meals that require multiple ingredients and a long time to prepare.
What to eat: 2-4 Food Groups
Okay, the message is clear, “Eat every 2-4 hours.” But what do we eat when the timer goes off?
My number 1 recommendation is to eat what you’re craving. There are many reasons we crave what we crave. Physiologically, there is evidence that shows we crave nutrients we need. When we’re stressed, sugar and fatty foods are often craved. Sugar guarantees what we’ll get quick energy, fatty foods ensure long-lasting energy. Both guarantee survival in the short and long terms.
That said, it can be hard to trust our cravings. Resisting cravings is one of the main reasons people begin working with me. And in today’s food system and marketing-heavy environment, I empathize with this struggle. For those who struggle to trust their cravings or maybe just wanting a little more structure around food, eating 2-4 food groups is my main recommendation.
FOOD GROUPS: I borrow the concept of food groups to make things a little easier but the history of Food Groups, in the way that we in the United States use them, have been evolving since the Food and Drug Administration (FDA) began using them in 1943.
The food groups are different from those in the FDA. They are also a product of my experience both as a dietitian as well as an intern growing food on various education farms. The intention of these food groups is to maximize nutrient-intake while reducing the cognitive labor it takes to make a meal or snack.
The 4 food groups I use for meal planning are grains, proteins, fats, and produce. Dairy has traditionally been included in the FDA and while calcium is an important nutrient to include in our daily intake, it doesn’t necessarily need to come from dairy.
GRAINS: pasta, rice, bread, baked goods, candy, etc.
PROTEINS: beans, hard cheeses, edamame, legumes, tofu, meat, yogurt, etc.
FATS: avocado, dressings, hummus, nuts, soft cheeses, etc.
PRODUCE: fruits and vegetables (canned, pickled, frozen, etc)
These 4 food groups will yield a comprehensive variety of both macro and micro nutrients. I recommend all 4 of them for a meal and at least 2 of them for snacks. (Yes, snacks are important if you’re eating 2-4 hours!)
Macronutrients: nutrients that help in energy resynthesis. Notice these foods don’t necessarily “give us more energy.” Rather, they help replenish energy we have used. Stimulants such as caffeine will “give energy” but we also need to make sure our bodies have the nutrients to back-up that energy boost. That’s where macronutrients come in. Think of it as caffeine will push the gas but macronutrients are the fuel that make the car go.
Micronutrients: vitamins and minerals. These are important for building tissues, supporting molecular reactions in the body, and ensuring all systems are good to go.
It’s worth noting that we cannot build and maintain tissues on micronutrients alone. We need both macro- and micronutrients to sustain our bodies and have a thriving metabolism. This is why we cannot live on supplements. We have to have food (or very complicated TPN formulas created by pharmacists) to survive and thrive.
Some examples of snacks and meals:
EXAMPLE MEALS:
Spaghetti bolignesies with broccoli and a bun with butter
Mac and cheese with sausages and frozen peas
Quinoa salad with sweet potatoes and chickpeas
Bagel sandwich with lox and cream cheese, with an orange on the side
Burger with coleslaw
EXAMPLE SNACKS:
Apple or banana and nut-butter
Cheese and crackers
Chips and salsa
Yogurt and granola
Ice cream and nuts
