Overall Nutritional Quality Index

I received this article in a newsletter I didn’t even know I signed up for.  A bunch of scientists from Yale developed a tool for assigning score to foods that reflects their nutritional value relative to the amount of calories they have.  The chart provided is a good reference point for people looking to tighten up their diet.

An Introduction to the Overall Nutritional Quality Index (click here for original article)


Scientists at Yale University have devised the Overall Nutritional Quality Index (ONQI), an important tool for anyone seeking to improve their diet. In essence, ONQI assigns each type of food a score (called a “NuVal”) between 1 and 100 that reflects how much nutrition the food provides relative to the number of calories it contains. For example, as you might guess, popsicles have a very low score because they have little nutritional value, but quite a few calories; on the other hand, broccoli achieves a score of 100 because it is packed with nutrients, and has very few calories.

In this article, we provide a more detailed description of the ONQI system and give tons of examples of foods and their scores. We also give general tips for how to follow these guidelines without actually having to memorize every value in the index. Finally, we have a few recipes that achieve very high NuVals to get you started.

The Method

The ONQI uses a patented algorithm to measure the nutritional quality of food. The ONQI algorithm first assesses the amount of over 30 different nutrients the food contains: this includes good nutrients like vitamins, minerals, and fiber, as well as sugar, salt, trans fats, and cholesterol. The system goes into considerable depth, further assessing the quality of proteins, fats, and carbs. For example, eggs have very high quality protein because their rich amino acid composition makes them easy to digest. On the other hand, protein in grains like pasta and rice lack essential amino acids and are considered lower quality.

The Rankings

Here is a chart that contains ratings for many different foods. This list is nowhere near comprehensive, but it should give you a good sense of how the rankings turn out. (Hint: they turn out pretty much how you would expect them to.)

NuVal Range Type of Food Example
75-100 Fruits Blueberries, orange, pineapple, apple, mango, banana, avocado
Meats Salmon, halibut, catfish, cod, oysters, swordfish steak
Vegetables Radish, cabbage, tomato, red onion, broccoli, green bean
Other Okra, oats, skim milk, quinoa
50-74 All Clams, whole milk, scallops, pasta
25-49 All Turkey, peas, prunes, chicken breast, steak, orange juice
0-24 All Popsicle, soft drink, crackers, milk chocolate, hot dog, white bread, bacon

General Guidelines

As you can see, the ONQI is a very strict rating system. Not many foods outside of fruits, vegetables, and fish make it into the top group. Moreover, many foods otherwise considered healthy – like turkey, peas, and chicken breast – do not make it out of the bottom half. Our suggestion here is to just avoid the bottom quarter, which is mostly composed of foods you know you should avoid, like hot dogs and soda. Try to get as much food as possible in the top quarter, but don’t worry if you dip into the second and third quarters. To avoid having to carry around this list – or worse yet, memorize the ONQI algorithm – here are two guidelines to help you structure your diet in accordance with the ONQI system.

  • Eat as many fruits and vegetables as possible. The foods that achieve ratings of 75-100 are overwhelmingly fruits and vegetables – and for good reason. Humans have eaten these foods for tens of thousands of years and they’re absolutely packed with nutrients.
  • Make fish your primary protein source. One not entirely obvious result of the ONQI system is the high ranking of so many types of fish. As you can see, most fish beat red meats, turkey, and chicken. Most fish are in the top quarter, while the others don’t make it above 50.

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