Written by Trevor Waldoch, MS, CN, CPT Certified Nutritionist | Certified Personal Trainer
Calorie deficit. Eat less, move more. Weight loss medications. Fasting. Potato diet. Each in search of weight loss. At the end of the day, if it is to be effective, the body needs to expend more calories than are taken in, a so-called “calorie deficit.”
Calories In < Calories Out = Weight Loss
The “calories in” side of the ledger is fairly straightforward, though with some nuance. It is
essentially how many calories enter the body. This is slightly different than how many calories
enter the mouth. Depending on the food, the state of one’s body, and the state of one’s
microbiome, each of us might actually absorb more or less calories from the same amount of
the same food. A well-known example is the almond, where an average of 75% of the calories
from the almond will be absorbed by the consumer, and the remaining 25% will either be eaten
up by bacteria in our guts or will end up in the toilet.
The “calories out” side of the ledger is even more complex. We have calories used for basal
metabolism (60-75% of calories expended for basic bodily functions), exercise activity
thermogenesis (5-15% of calories, what you do at the Yakima Athletic Club), non-exercise
activity thermogenesis (15-30% of calories, unplanned movement throughout the day, like
fidgeting), and the thermic effect of food (8-10% of calories, used to metabolize foods). The
actual percentage of calorie expenditure rom any one of these buckets may vary greatly
depending on the state of one’s body and diet.
For example, eating higher protein tends to raise the energy expended on the thermic effect of
food, since protein is more energetically demanding to process than carbohydrates or fats.
Your body literally has to use more energy to break the protein down. Exercise activity
thermogenesis can vary widely from person-to-person and day-to-day. Exercise activity
thermogenesis also impacts basal metabolic rate. Someone who is sedentary compared to
someone running a marathon each day for a week is likely spend a drastically different amount
of calories on immune function. There just isn’t enough free energy laying around to take care
of basic housekeeping within the body. This is why people training excessively can suppress
their immune systems or they may experience hormonal disruptions.
Any weight loss or weight maintenance effort comes down to avoiding the perils of overeating.
In our modern food environment with endless, delicious processed foods and tasty delicacies
beckoning for our stomach room, eating less can be much easier said than done. Rather than
just muscling our way to eating less and tolerating the extra hunger, there are some strategies
one can leverage to make eating less a bit more enjoyable.
A study by Susanna Holt in 1995 looked to uncover which elements of common foods led to a
feeling of more or less satiety, or a feeling of fullness. The researchers fed volunteers portions
of 38 different foods, all of which totaled 240 calories. The study volunteers reported how full
they felt every 15 minutes. Holt and colleagues uncovered some common qualities of foods
that were filling versus those that were not.
The quality of a food that most predicted whether or not it was filling was calorie density. Put
another way, it was the volume of a food per calorie. Foods with fewer calories per unit volume
were more filling. Salad greens, for example, have very few calories per cup. A cup of cooked
spinach would have about 42 calories. The salad greens can take up a lot of space in the
stomach at the expense of very few calories. Olive oil, on the other hand, is extremely caloriedense.
There are nearly 2,000 calories in a cup of olive oil. That’s the daily caloric intake for
many people, but it would not come with much satiety.
Next on the list was palatability. The more delicious the food was, the less filling it tended to
be. The brain finds these palatable foods extremely valuable and will drive us to continue to eat
more. By sticking to simple, whole foods, we can moderate our calorie intake without feeling
excessively hungry.
Third on the list is a food’s fat content. The more fat a food contained, the less filling it tended
to be. This makes sense when we are controlling for calories. Dietary fats have over twice as
many calories per gram than carbohydrates or protein. This means that the more fat there was
to the 240 calorie serving, the smaller it was. This is why added fats like oils and butter can be
problematic if they are consumed in excess. They can add a lot of calories without helping us
to feel satisfied with the meal.
The fourth greatest contributor to feeling full was the fiber content of a food. The more fiber it
had, the more full it tended to make people feel. Whole grain bread tends to have more intact
fibers than white bread, and so tends to make one feel more full even if calories are about the
same between the two. Fibers attract water and swell within the gut, increasing the sensation
of fullness. They also slow the emptying of contents from the stomach, helping us to feel
satisfied for longer after a meal.
Finally, protein content of these foods were a major contributor to satiety, or feeling full. Per
calorie, it is more filling than either carbohydrates or fats. The small intestines and the pancreas
both detect if dietary protein has recently been consumed. They then relay a single to the brain
that there is protein being digested, and the brain releases chemical messengers to make us
feel more full.
With these qualities in mind, we are best to avoid foods that are calorically dense, extremely
palatable, include added fats, and lack fibers and proteins. Unfortunately for us, our grocery
stores are filled with products in boxes and wrappers that fit this diabolic description nearly
perfectly! By avoiding the aisles in the middle of the store and sticking to the outsides with the
whole foods, we can support our bodies as we try to manage our calories. Beans, lentils, fresh
fruit, vegetables, fresh meat and seafood, oatmeal, avocado, yogurt, and eggs will all be great
options to feel satisfied after meals. Believe it or not, potatoes were actually the #1 most filling
food in the study. Rather than white-knuckling our way through a calorie deficit, we can
leverage these qualities next time we shop to make calorie maintenance a bit more …
palatable.