Why Eat Whole Grains?

By Dietitian and Wellness Educator, Elizabeth Kahn

You hear a lot these days about eating whole grains. But that is just more useless advice that you can ignore, right? Wrong. But, let me explain why you want to eat whole grains and maybe you will be more inclined to do so. Let’s take whole wheat for example. Whole wheat has many more nutrients than white flour. Let’s start with amino acids, the building blocks of protein.

The whole wheat grain has three main parts: the bran, germ and endosperm.

The parts of the whole-wheat grain with the most amino acids are the bran and germ — the parts removed when making white flour. All that is left in white flour is the endosperm, which not only has fewer amino acids, but is full of gluten. Food manufacturers love gluten because it is extremely pliable and tasty. Many people are developing gluten allergies as a result of the overconsumption of white flour.

Protein quality depends on all the essential amino acids being present in the right amounts, and in complete proteins they are. According to a measurement by the Institute of Medicine, a complete protein has a score of 100. Letter grades — based on numeric
scores — for the individual parts of the wheat grain are:

Germ: A

Bran: C

Endosperm: F

For nutrients like amino acids to do their jobs effectively in the body they must be balanced, and in whole grains they are. Here is how many amino acids are lost during processing white flour.

Amino acid  Units  Whole-Wheat Flour  White Flour
Tryptophan

G

0.254

0.159

Threonine

G

0.474

0.351

Isoleucine

G

0.610

0.446

Leucine

G

1.111

0.887

Lysine

G

0.454

0.285

Methionine

G

0.254

0.229

Cystine

G

0.380

0.274

Phenylalanine

G

0.775

0.650

Tyrosine

G

0.480

0.390

Valine

G

0.742

0.519

Arginine

G

0.770

0.521

Histidine

G

0.380

0.287

Alanine

G

0.584

0.415

Aspartic acid

G

0.844

0.544

Glutamic acid

G

5.190

4.349

Glycine

G

0.662

0.464

Proline

G

1.706

1.498

Serine

G

0.775

0.645

Whole wheat has more of every amino acid than white flour.

There are many other nutrients that are affected in processing whole wheat into white flour.

Nutrient

Units

Whole-Wheat
Flour

White
Flour 

Macronutrient
Energy

kCal

407

455

Protein

G

16.44

12.91

Carbohydrate

G

87.08

95.39

Fiber

G

14.6

3.4

Minerals
Calcium

Mg

41

19

Iron

Mg

4.66

1.46

Magnesium

Mg

166

28

Phosphorus

Mg

415

135

Potassium

Mg

486

134

Sodium

Mg

6

2

Zinc

Mg

3.52

0.88

Copper

Mg

0.458

0.180

Manganese

Mg

4.559

0.853

Selenium

Mcg

84.8

42.4

Vitamins
Thiamin

Mg

0.536

0.150

Riboflavin

Mg

0.258

0.050

Niacin

Mg

7.638

1.562

Pantothenic acid

Mg

1.210

0.547

Vitamin B-6

Mg

0.409

0.055

Folate

Mcg

53

32

Choline

Mg

37.4

13.0

Betaine

Mg

87.4

0.0

Carotene, beta

Mcg

6

0

Vitamin A, IU

IU

11

0

Lutein + zeaxanthin

Mcg

264

22

Vitamin E (alpha-tocopherol)

Mg

0.98

0.07

Vitamin K (phylloquinone)

Mcg

2.3

0.4

Fats
Fatty acids, saturated

G

0.386

0.194

Fatty acids, monounsaturated

G

0.278

0.109

Fatty acids, polyunsaturated

G

0.935

0.516

Whole wheat has four times the amount of fiber white flour does. Whole wheat also has fewer calories, carbohydrates and more protein than its less healthy counterpart. There is about fifty percent less calcium, about one-third the amount of iron, and one-sixth the amount of magnesium in white flour. The list goes on and on but you can see it for yourself.

These are a few of the reasons to eat more whole grains. Whole grains have a lot more of the nutrients we need to function, learn, maintain sufficient energy levels for our busy lifestyles and thrive.

Sources:

  1. Self Nutrition Data. (n.d.). Know what you eat. Retrieved April 4, 2011, from http://nutritiondata.self.com.
  2. United States Department of Agriculture. (2009). National nutrient database for standard reference, release 22. Retrieved December 30, 2009, from http://www.nal.United States Department of Agriculture.gov/fnic/foodcomp/search/.