Will eating fat make you fat?
No! Many students confuse dietary fat
(the fat that we eat) with adipose tissue (the fat on our bodies).
Dietary fat does not automatically stick to your waist, legs, butt,
and thighs. Only excess calories from dietary fat makes you gain
body fat. Excess calories from anything makes you gain body fat.
If you include fat in a meal plan that contains an appropriate
number of calories, the fat in your food will be burned as energy.
If you eat too many calories (regardless of the
source--carbohydrates, protein, fat, or alcohol), the excess
calories will be converted to and stored as body fat.
There are more fat-free products today than ever before, but
ironically, we are fatter today than ever before. Why? Fat free
doesn’t mean calorie free! One fat-free Snackwell’s devil’s food
cookie has the same number of calories as one full-fat Oreo cookie.
And we tend to eat more of the fat-free ones because they are
marketed as being more “healthy.”
Read on to learn…
How dietary fat CAN become
What's the difference between
saturated and unsaturated fat.
Which type of fat is best for
achieving your energy, health, and fitness goals.
How can dietary fat become fattening?
Gram for gram, dietary fat has more than twice the calories as
protein or carbohydrate (9 calories per gram vs. 4 calories per
gram). So, if you eat a lot of fatty foods, you will likely be
eating a lot more calories every day. This isn’t a problem if you’re
very active and need those extra calories. But, if you don’t need
those extra calories, the excess calories may be converted to and
stored as body fat.
Look at the calorie differences between equal portions of high fat
vs. low fat foods:
|3 oz. grilled skinless chicken
|3 oz. broiled hamburger patty
|1 ladle (3 T.) Ranch salad
|1 ladle (3 T.) Red wine vinegar
Also, it’s easier for your body to convert excess calories from
dietary fat to body fat than it is to convert excess calories from
carbohydrate or protein to body fat. Why? It simply costs more
calories to convert excess carbohydrate or protein calories to body
fat, so fewer calories remain for storage. For example, if you
overeat 100 calories of carbohydrate or protein, 15-25 of those
calories will be used to convert the calories into body fat (and
only 75-85 of the calories will be stored). On the other hand, if
you overeat 100 calories of fat, only 5 calories will be used in the
conversion (and 95 of the calories will be stored).
Purpose of fat
The fat in foods and the fat on our bodies serve many important
1. In foods, fat serves the following roles:
Nutrient: Fat supplies essential fatty acids, which are needed for
normal growth of infants and children and for production of
hormone-like compounds (called eicosanoids) that regulate a wide
range of body functions and keep you healthy.
Transport: Fat carries fat-soluble vitamins (A, D, E, and K) and phytonutrients (like beta-carotene) and assists in their absorption.
Sensory: Fat contributes to the smell and taste of food.
Texture: Fat helps make foods tender (especially meats and baked
Satiety: Fat gives food satiety, so you feel full and satisfied
longer after a meal.
Fat provides a concentrated source of calories. This is good if
you are traveling long distances, expending a lot of energy, and
carrying your own food (i.e. hiking, backpacking, hunting). It’s
also good for people with high calorie needs who are trying to gain
lean body mass.
2. In the body, fat serves the following roles:
Fats are the body’s main form of
stored energy (important in times of illness and diminished food
Fats provide most of the energy to fuel muscular work.
Fat pads internal organs and insulates our bodies against
Fats form the major material of cell membranes (especially brain
and nerve cells).
Fats are converted to many important hormones (including sex
Fat is a good thing! It's only when there is too much of a good
thing that it can become problematic.
Types of Fat: saturated vs. unsaturated
Just like there are two general categories of carbohydrates, there
are two general categories of fats based on their chemical
structure: saturated and unsaturated fats. These fats have very
different effects on your health.
1. Saturated fats
Saturated fats are the type of fat that is generally associated with
poor health. They tend to increase the “bad” cholesterol in your
blood and increase your risk of heart disease. Saturated fats tend
to be solid at room temperature, and they tend to be most
concentrated in animal sources of fat (including butter, cream, beef
fat, chicken skin, whole fat milk, cheese, and ice cream).
Exceptions: Tropical oils (including coconut, palm, and palm kernel
oils) are very high in saturated fats. Fatty fish (like salmon) are
2. Unsaturated fats
Unsaturated fats are the type of fat that is generally associated
with good health. They tend to lower the “bad” cholesterol in your
blood and decrease your risk of heart disease. Unsaturated fats tend
to be liquid at room temperature, and they tend to be most
concentrated in plant sources of fat (including vegetable oils,
olives, avocados, nuts, and peanut butter).
Exception: Vegetable oils that have undergone a process called
hydrogenation to make them more solid (i.e. margarine, vegetable
shortening, and partially hydrogenated vegetable oils) have high
amounts of trans fat. These trans fats are just as damaging to your
health as saturated fats. Trans fats are hiding in many processed
foods (i.e. cereals, baked goods, sports bars) and fried fast foods,
so be sure to read your food labels.
There are two general subdivisions of unsaturated fats: mono and
poly unsaturated fats.
Monounsaturated fats are generally regarded as the most heart
healthy. Good food sources include olive and canola oils, most nuts,
peanut butter, avocados, and olives. For optimal health, most of the
fat in your diet should come from these sources.
Polyunsaturated fats include the omega 6 and omega 3 families of
fat. Much of the unsaturated fat in the typical American diet is
from the omega 6 family (since most food products use corn, soybean,
safflower, and sunflower oils). For optimal health, however, we
should try to include more omega 3 fats in our diet. The best food
source of omega 3 fat is fatty fish (like salmon and mackerel).
Smaller amounts can also be found in plant foods like walnuts,
flaxseeds, soy, and canola oils.
While unsaturated fats are generally good for your heart health,
they have the same number of calories as saturated fat. So, keep
portion sizes small, and use them in place of saturated and trans
A healthy eating plan for most students contains anywhere between
20 and 35% of calories from total fat. This amounts to 44-78 g of
fat for an active women eating a 2000 calorie diet or 62-109 g of
fat for an active man eating a 2800 calorie diet. Given these goals,
it's possible to see that even a high fat dessert (with 25 g of fat
per serving) CAN fit into your healthy eating plan so long as it is
balanced with other low fat choices throughout the day.
One of the problems with some of the popular low carbohydrate
diets is that they are too liberal with fat, especially the
On the other hand, one good point about the popular low
carbohydrate diets is that they are not as restrictive in fat as the
super low fat diets that used to be popular. Super low fat diets
typically contain <10% of calories from fat (that's < 22 g of fat
for a 2000 calorie diet). When fat is too restricted, you tend to
feel hungry and unsatisfied all the time. This can often lead to
carbohydrate cravings, over-consumption of fat free (but high sugar
and high calorie) snacks, and weight gain. Inadequate fat
consumption has also been associated with depression.
More important than the total amount of fat you are eating is the
type of fat you are choosing. If you are consuming a higher fat diet
(with 30-35% of total calories from fat), make sure most of it is
coming from monounsaturated and omega 3 fats.
For optimal health, aim to keep saturated and trans fat as low as
possible (<10% of total calories).
Click here for tips on finding
low fat and healthy fat
alternatives to foods that contain a lot of saturated or trans fat.
If the alternatives just don’t satisfy you, try using less of the
real thing and/or choosing the food less often.
Remember, there is no such thing as “good” or “bad” foods. Balance
your choices so that your overall eating plan is low in saturated
and trans fat.
Sheri Barke, MPH, RD
COC, Student Health & Wellness Center