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Consuming too little of any one food group, or
too much, can cause imbalances that can be
detrimental to one’s health.
Making calories count
At the heart of many diet trends is the
calorie. For people trying to lose weight,
counting and limiting how many calories they
consume becomes a regular and sometimes
tedious task.
While it’s true that, of the macronutrients,
fat provides the most food calories at nine
kilocalories per gram (g). Proteins and
carbohydrates both provide four
kilocalories per gram.
So, what is a calorie anyway, and how
much should we be getting from protein
sources? A calorie with a lower case “c”
is a unit of measurement, defined as
the amount of heat energy required
to raise the temperature of one gram
of water by one degree Celsius, for
example, from 14. 5 °C to 15. 5 °C.
When talking about food, 1,000 calories
(one kcal) is often noted Calorie with a big
“C.” A medium banana with 70 Calories (70
kcal) provides 70,000 calories of energy.
The National Academy of Medicine suggests that 10% to 35%
of the calories we consume each
day should come from protein.
Most sources say 52 g of protein per day and
46 g of protein per day are adequate for teen-
age boys and girls, respectively, or 0.85 g per
kilogram of body weight (1 kg is the same as
2. 2 pounds). Teen athletes might need more.
But what can happen if you have too much
protein? Anthony might not realize it, but he
could be consuming more calo-
ries than he needs through
the additional protein in
his diet. If he is eat-
ing more calories
than he is burning
each day, even in
the form of pro-
tein, those extra
calories might be stored by his body as fat. He
may gain the weight he is looking for, but not
in the form he wants.
Conversely, Sarah might not be getting
enough calories. According to the National
Academy of Medicine’s Dietary Refer-
ence Intake, if Sarah is 5-feet,
4-inches tall and weighs 120
pounds, with her activity
level she should consume
more than 2,300 Calo-
ries a day, including at
least 58 g of protein.
However, Sarah has
increased her protein
at the expense of other
foods, such as whole
grains, and the healthy
fats found in foods, such as
avocado and nuts.
Why you really need
proteins
Protein is important in our diets because it
provides the 20 amino acids our bodies need
to build new proteins that keep us alive.
These important macromolecules make up
most of our physical structure (skin, hair, mus-
cles, and organs), act as enzymes that catalyze
reactions, enable our nerves to communicate,
and help protect us from getting sick.
There are nine essential amino
acids we must get from food
because our bodies cannot pro-
duce them. These are: 1) histi-
dine, 2) leucine, 3) tryptophan,
How should you fill your
plate? The answer is: It’s
complicated—it depends
in large part on your age,
weight, and physical
activity level. Go to
choosemyplate.gov for
more information, or talk
to your doctor.
provides the 20
amino acids our
bodies need to
build new proteins
that keep us alive.
