One of the
biggest problems with the typical Western diet is the fact that much of our
food is refined, or highly processed. The refining process removes important
nutrients like fiber, iron and B vitamins, and this is done by food
manufactures for two reasons. Firstly, it's to give the end project a softer
texture, and secondly it's done to extend the shelf life of the resulting
product. A heavily processed food is going to last longer on the supermarket
shelf because pests, like mold for example, are less attracted to foods that
are low in nutrients. A hamburger that's highly processed will spoil much more
slowly than a hamburger made at home with mostly natural ingredients.
But the
question is, if highly processed food is so low in nutrients that the pests
don't even want to eat it, how healthy can it be for us?
In fact, the
nutrient content of any given food is directly related to the spoil rate of
that food. Foods that are very low in nutrients spoil much more slowly than
foods that are rich in nutrients. Thinking about the nutrient density of the
food is another conceptual way of making sensible food decisions. The nutrient
density of a food can be thought of as the amount of nutritional value,
including vitamins, minerals, and fiber, divided by the calories, or energy
content, of that food. For example, a glass of soda is high in calories without
providing much in the way of nutritional value. Foods that provide lots of
calories with very little nutritional value are sometimes called energy dense
foods, but their nutrient density is low. A bunch of fresh spinach, on the
other hand, would be an example of a nutrient dense food because its
nutritional value is relatively high compared to its caloric content. When
people talk about fast food being cheaper than fresh food, they're often
referring to the fact that the cost per calorie of highly processed food is
lower than that of fresh, whole food. This is often true because highly
processed food is so high in calories that the cost per calorie is relatively
low. But, if we instead look at the cost of food per unit of nutrient density,
then buying fewer calories of higher nutrient density food is a much better use
of our food budget.
In the midst
of a serious epidemic of obesity, avoiding empty calories should be near the
very top of our list of priorities. One of the reasons why highly processed
food is usually higher in calories is that in order to make these products
sell, significant amounts of fat, sugar, and salt are added to make the
nutrient-stripped foods taste good.
Additives
like colorants, artificial flavors, stabilizers, and other preservatives, are
also added to enhance packaged products and maintain the illusion that we as consumers
have many choices when we walk through the supermarket aisles.
The last
thing we need to be aware of are highly processed foods that masquerade as
healthy foods. These are products that have synthetic nutrients added back to
them after they've been refined, and this is usually done to make the product
seem healthy to the nutrition aware consumer. It's important to remember that
the most nutritious foods, like broccoli, don't come in packages that tell us
how healthy they are.
