What is Nutrient Density?

By Professor Jack A. Bateman

Nutrient Density is a calculated value that defines the quality of a given food. Overall nutrient density (ND) is calculated by summing the essential nutrients in a food divided by the energy in kilocalories (kcals). Since this is a complex, cumbersome calculation, the term is used mostly with respect to a single nutrient, i.e. nutrient density with respect to magnesium in which the mg of magnesium is divided by the kcals. In essence the calculated value gives you a comparison between food groups that tells you how you can get the most of a nutrient for the fewest number of Calories (kcals).
Essential nutrients include protein, two polyunsaturated fatty acids (linoleic acid and alphalinoenic acid), vitamins, minerals and water. Since protein is an essential nutrient we can look at various common protein sources and compare their nutrient density with respect to protein. Since nutrient density is not dependent on the amount of food, we do not need to concern ourselves with how much of a food we are talking about. Hamburger has a ND of 0.093, Prime rib of beef has a ND of 0.060, and a poached egg has a ND of 0.050. Lean ham has a ND of 0.146. White meat chicken has an ND of 0.179. Lobster has a ND of 0.22. Salmon has a ND of 0.153. Shrimp has a ND of 0.226. You can see from this limited list that seafood seems to have the highest nutrient density with respect to protein.
This parameter becomes really important when comparing sources of micronutrients (vitamins and minerals). Most people are deficient in vitamin B-6 (pyridoxal). The top sources of vitamin B-6 are spinach with a ND of 0.060. The second best source is broccoli with a ND of 0.007. The third and fourth are banana with a ND of 0.006 and Salmon with a ND of 0.005. You can see that getting even an RDA level of vitamin B-6 of 2.0 mg is going to be difficult. You would need to eat 4.5 cups of spinach or 6.3 cups of broccoli in order to get 2.0 mg of the vitamin. It is easy to understand why deficiencies are so common. This is exactly why a multiple vitamin is good insurance for a healthy life. When you realize that every protein molecule made must have vitamin B-6 present, it becomes a necessity that you provide the adequate amounts for your body to function properly.
A most interesting comparison is that of potassium, a mineral that is essential for electrolyte balance, proper nerve functioning, proper heart rhythm, and many other functions. It is essential in that too much or too little potassium and you die. We have all been schooled by Chiquita Corporation that bananas are the food choice to receive your potassium. However, when you look at potassium containing food and their nutrient densities with respect to potassium, you get an entirely different picture. Beet greens contain the highest ND at 26, followed by Chinese cabbage at 19.6, celery at 18.9, parsley at 16.8, cauliflower and mushrooms at 14. Where is the banana? It turns out that banana is 45th on the list of potassium rich food with a ND of 4.3. How can we be fooled so badly? It is true that one banana gives us 451 mg of potassium, but one sweet potato has the same Calorie content and 397 mg of potassium. 48 Calories or two cups of cauliflower would provide you with 712 mg of potassium.
Nutrient Density values are a valuable tool in choosing high quality foods. It is reported in the research literature that low nutrient density diets are leading our children to obesity. For more information on nutrient densities go to our web site at www.thevitaminsupplementstore.com