On a recent trip to the grocery store, I overheard a
female customer ask the meat counter assistant which beef roast would be the
most lean. The customer was a trim figure in athletic
attire, and a young girl (presumably her daughter) loitered by the shopping
cart. This customer embodied the ever-more
health conscious consumer eager to provide the most nutritious food for her
family. However, the public is often
bombarded with vague or contradictory statements about food (“Beef is bad,” “Eggs
are good,” “Beef is good,” “Eggs are bad,” “Chia seeds and acai berries!”),
making purchasing decisions difficult.
Fortunately, nutrition labels and ingredient statements on processed
foods can allow shoppers to make comparisons and choices that fit their health needs. But for many raw foods such as meats, fruits,
and vegetables, the nutrient information is often not displayed. This can lead to questions like that of the
aforementioned customer. This post of Meat Salads offers some clarification on
the types and amounts of fat found in different fresh meats.
Perhaps one of the most misunderstood concepts of food
composition is “fat.” The word is heavy
with negative connotation, but without fat in the diet, humans and animals
would fare very poorly. After all,
dietary fat facilitates the absorption of vitamins A, D, E, and K; allows for
the formation and function of skin, brain, and nervous tissues; encourages the
feeling of satiety, and enhances the flavor, aroma, and texture of food (Meat
Poultry Nutrition, 2013). Still, overconsumption
of fat can be detrimental for human health, so limiting fat intake to only
20-35% of total daily calories is recommended for almost everyone (Centers for
Disease Control and Prevention [CDC], 2012a).
Also, the Dietary Guidelines for
Americans 2010 recommends further that calories from saturated fat
constitute only 10% of total daily
calories (CDC, 2012a). Saturated fat and
its counterpart, unsaturated fat, exist in animal muscles in different ratios depending
on the species and muscle function/location.
This means different types of meat will have various levels of saturated
and unsaturated fat. Table 1 gives a
simplified explanation of the two fat types, and Table 2, with data from the
USDA National Nutrient Database for Standard Reference, Release 26, gives
examples of how fat differs among fresh meats.
Table 1: A
simplified explanation of saturated and unsaturated fats (fatty acids). Saturated fatty acids are more often used for
energy storage and insulation whereas unsaturated fatty acids are used for cell
membrane structure, signaling molecules, and other functions.
|
Fat Type
|
Definition‡
|
Diagram‡
|
Saturated
|
Every carbon atom in the hydrocarbon chain is bound to
as many hydrogen atoms as possible.
The fat has a rigid structure at room temperature.
|
 |
Unsaturated
|
At least two carbon atoms in the hydrocarbon chain are
not bound to as many hydrogen atoms as possible. At least 1 double bond (circled in
illustration) is present. The fat has
a fluid structure at room temperature.
When only 1 double bond is present, the fat is “monounsaturated.” When 2 or more double bonds are present,
the fat is “polyunsaturated.”
|
‡ Carnegie Mellon University, 2006
Table 2: A
comparison of meat from beef, pork, poultry, eggs, and fish. Meat will vary in saturated and unsaturated
fats depending on the species and muscle of origin.
Species
|
Cut*
|
Saturated fat (g/100 g meat)^
|
Monounsaturated fat (g/100 g meat)^
|
Polyunsaturated fat (g/100 g meat)^
|
Beef
|
Chuck pot roast (1/8” exterior fat)
|
7.254
|
7.697
|
0.684
|
Beef
|
Top blade steak (0” exterior fat)
|
2.817
|
3.409
|
0.389
|
Beef
|
Strip steak (1/8” exterior fat)
|
2.100
|
2.545
|
0.208
|
Beef
|
Tenderloin roast (0” exterior fat)
|
2.363
|
2.578
|
0.454
|
Beef
|
Brisket flat half (1/8” exterior fat)
|
8.951
|
9.498
|
0.844
|
Beef
|
Flank steak (0” exterior fat)
|
2.978
|
2.924
|
0.277
|
Pork
|
Shoulder
|
4.140
|
5.367
|
2.474
|
Pork
|
Loin chops
|
2.450
|
2.985
|
0.878
|
Pork
|
Cured ham steak
|
1.440
|
1.960
|
0.470
|
Chicken
|
Breast (skinless)
|
0.479
|
0.586
|
0.360
|
Chicken
|
Thigh (skinless)
|
0.932
|
1.272
|
0.799
|
Turkey
|
Breast (skinless)
|
0.344
|
0.284
|
0.355
|
Turkey
|
Thigh (skinless)
|
0.782
|
0.749
|
0.722
|
Egg
|
Large, whole
|
1.563
|
1.829
|
0.956
|
Salmon
|
Atlantic, wild
|
0.981
|
2.103
|
2.539
|
*Except for the cured ham steak, the given values are for
the raw meat servings.
^All values are presented as “g fat/100 g meat” except
for the egg (g fat/50 g).
From Table 2, differences in fat content among species
and cuts are clearly seen. Since the CDC
recommends limiting fat, especially saturated
fat, intake, the values listed above might not be so welcoming for beef
fans. However, the CDC also reports that
saturated fat intake can be lowered when customers choose beef cuts with less
marbling and then trim all visible fat from the outside of a cut (CDC, 2012b). Marbling refers to the amount of
intramuscular fat (the white flecks or specks) visible in meat. As Figure 1 below shows, meat can be heavily
laced with intramuscular fat or essentially devoid of it. While more marbling is appropriate for a very
indulgent filet mignon at a steakhouse, less marbling is more appropriate for cuts
eaten more frequently at home, especially if limiting saturated fat intake is
part of your lifestyle.
Just like the lady at the meat counter, more and more
people want to know the advantages and disadvantages of foods to make better
choices for themselves and their families.
Though following the CDC’s recommendation of limiting fat calories to
20-35% of total daily calories is key to avoiding many health problems, not all
foods in the grocery store come with nutrition labels that declare their fat
content. However, having a basic
understanding of saturated and unsaturated fats, comparing values from the USDA
National Nutrient Database, and being able to differentiate leaner cuts from
those with more fat will enable consumers to buy a wide range of meats for all
needs, tastes, and occasions. Remember:
variety is key. Enjoy salmon, eggs, chicken,
turkey, shrimp, pork, beef, lamb, and other meats to experience a multitude of
flavors while providing your body with essential nutrients.
References
Carnegie Mellon University (2006). Department of Biological Sciences:
Interactive Animations. Retrieved from http://telstar.ote.cmu.edu/biology/MembranePage/index2.html
Centers for Disease Control and Prevention (2012a). Dietary Fat.
Retrieved from http://www.cdc.gov/nutrition/everyone/basics/fat/index.html
Centers for Disease Control and Prevention (2012b). Saturated Fat. Retrieved from http://www.cdc.gov/nutrition/everyone/basics/fat/saturatedfat.html
Meat Poultry Nutrition (2013). Skinny on Dietary Fat. Retrieved from http://www.meatpoultrynutrition.org/ht/d/sp/i/26061/pid/26061.
USDA (NA).
National Nutrient Database for Standard Reference Release 26. Retrieved from http://ndb.nal.usda.gov/ndb/search/list
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