Frequently Asked Questions (FAQ)

Click each heading for answers to your questions.
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Do you have an app?
Yes, we have an app for mobile and desktop devices which you can install here.
Who creates all this information? is created by Paul House who holds a degree in statistics from North Carolina State Universty and worked in public health before founding

The curated food lists were written by Daisy Whitbread who holds a masters degree in nutrition from King's College London.

Namimbia Torres serves as an advisor to the project and holds a masters degree in nutrition science and policy from Tufts University.

As part of our editorial process, articles are medically reviewed by doctors.

For more information, please see the about page.

Do you have a nutrient ranking for...?
Maybe, check the nutrient ranking listings, and the nutrient ranking tool. If the nutrient you are looking for is not there feel free to send in your requests.
What foods will lower my cholesterol?
Check the article on cholesterol lowering foods.
What is the difference between the Recommended Daily Allowance(RDA) and the Daily Value(DV)?
According to Office of Dietary Supplements: RDAs are recommended daily intakes of a nutrient for healthy people. They tell you how much of that nutrient you should get on average each day. RDAs are developed by the Food and Nutrition Board at the Institute of Medicine of the National Academies. They vary by age, gender and whether a woman is pregnant or breastfeeding; so there are many different RDAs for each nutrient.

DVs, established by the U.S. Food and Drug Administration (FDA), are used on food and dietary supplement labels. For each nutrient, there is one DV for all people ages 4 years and older. Therefore, DVs aren't recommended intakes, but suggest how much of a nutrient a serving of the food or supplement provides in the context of a total daily diet. DVs often match or exceed the RDAs for most people, but not in all cases.

DVs are presented on food and supplement labels as a percentage. They help you compare one product with another. As an example, the %DV for calcium on a food label might say 20%. This means it has 200 mg (milligrams) of calcium in one serving because the DV for calcium is 1,000 mg/day. If another food has 40% of the DV for calcium, it's easy to see that it provides much more calcium than the first food.

For more information see our guide to Daily Intakes and Daily Values.

Why is data sometimes missing?

Missing data has not been collected by the USDA, or reported by food manufacturers. When data is missing from the source, we cannot report it.

No data set is perfect and missing data is a common problem when analyzing data.

Missing data does not mean the value is equal to 0. The value is unknown, and may in fact be very high in value.

Please find similar foods that may have the data and give some clue as to what the actual value may be.

You can search for similar foods using the nutrition facts search tool. Or you can also find foods high or low in a particular nutrient using the nutrient ranking tool.

Are the weights for cooked foods given for before cooking or after?

The weight of a food, for example, cooked broccoli, is given as the weight after the food has been cooked. See this example of cooked vs raw broccoli.

Why do the totals of amino acids not equal the total protein in the food?
Measures of protein are seen as "Total Protein", "True Protein", and "Amino Acids". Total Protein is derived by the Kjeldahl method which is the dominant method to gather protein content. This is because the Kjeldahl method is easy to replicate and consistent. However, the Kjeldahl method uses total nitrogen multiplied by a conversion factor, and is often an overestimate of true protein. Since individual amino acids are much more difficult to measure than total nitrogen, true protein numbers are difficult to find. As such, Total Protein is commonly reported on the site in line with the USDA Food Data Central and most product lables. MyFoodData will attempt to report true protein where possible.
How are omega 3 fats calculated?
Omega 3 fatty acids are calculated as the total of:
  • alpha-Linolenic Acid (ALA) (18:3 n-3 c,c,c)
  • Eicosapentaenoic (Timnodonic) Acid (EPA) (20:5 n-3)
  • Docosapentaenoic Acid (DPA) (22:5 n-3)
  • Docosahexaenoic Acid (DHA) (22:6 n-3)
  • n-3-Eicosatrienoic Acid (ETE) (20:3 n-3)
In cases where none of the above fats are available (ALA, EPA, etc...) then the value for undifferentiated-Octadecatrienoic (18:3 undifferentiated) is used as an approximation.
How are omega 6 fats calculated?
Omega 6 fatty acids are calculated as the total of:
  • Linoleic acid (18:2 n-6 c,c)
  • gamma-Linolenic Acid (GLA) (18:3 n-6 cis cis cis)
  • cis-cis-n6-Eicosadienoic Acid (20:2 n-6 cis cis)
  • Dihomo-gamma-linolenic acid (DGLA) (20:3 n-6)
  • Arachidonic acid (AA) (20:4 n-6)
In cases where none of the above fats are available (Linoleic acid, GLA, etc...) then the value for Octadecadienoic Acid (18:2) is used as an approximation.
I tried to caluculate the calories from the macronutrients using the 4,4,9 rule and it doesn't match. Why?

The 4,4,9 rule is a general rule of thumb, however, it does not apply to all foods. Certain foods have different factors for their carbohydrates, protein, and fat.

For example, the 4,4,9 rule does not apply to foods that are high in fiber, sugar alcohols, or other non-digestible carbohydrates.

Per the documentation from the USDA:
"Food Energy. Food energy is expressed in kilocalories (kcal) and kilojoules (kJ). One kcal equals 4.184 kJ. The data represent physiologically available energy, which is the energy value remaining after digestive and urinary losses are deducted from gross energy. Energy values, with the exception of multi-ingredient processed foods, are based on the Atwater system for determining energy values. Derivation of the Atwater calorie factors is discussed in “Agriculture Handbook 74” (Merrill and Watt, 1973). For multi-ingredient processed foods (source codes 8 or 9; for more information on source codes, see p. 34) kilocalorie values generally reflect industry practices (as permitted by NLEA) of calculating kilocalories as 4, 4, or 9 kilocalories per gram of protein, carbohydrate, and fat, respectively, or as 4, 4, or 9 kilocalories per gram of protein, carbohydrate minus insoluble fiber, and fat. The latter method is often used for high fiber foods."