ActiveNutrition is an ActiveRecord-backed collection of models for storing and retrieving nutritional information from the USDA's Nutrient Database.

gem install active_nutrition

ActiveNutrition is meant to be used within a Rails application, but it should work within any Ruby project that uses ActiveRecord 3.0 or greater.

require 'active_nutrition'

In a (possibly Rails) gemfile:

gem 'active_nutrition', '~> 0.5.0'

ActiveNutrition has the ability to fetch the current Nutrient Database files from the USDA's website and load them into your ActiveRecord-supported database. As long as you've established a connection via ActiveRecord, you should be able to import the nutrient data.

With Rails:

bundle exec rake active_nutrition:migrate active_nutrition:rebuild

Without Rails:

require 'active_nutrition'

ActiveNutrition.migrate
ActiveNutrition.rebuild

Note: The full data import could take anywhere from 30 minutes to a few hours depending on how powerful your computer is. Note: You can use an instead of active_nutrition for all rake tasks, eg. rake an:rebuild.

ActiveNutrition provides a simple #search method that executes a SQL LIKE statement and returns an array of Food objects:

ActiveNutrition.search("olive oil")

Each Food object offers these methods

1. #nutrition_facts: Returns an array of NutritionFact objects for each kind of nutrient associated with this food. Examples include the amount of protein, fat, and sodium. Each NutritionFact object knows its unit (eg. miligrams, grams, etc) and amount per 1 gram of the food.
2. #weights: Returns an array of common unit weights for this food (eg. cups, tablespoons, etc) and their gram equivalents.
3. #food_group: Returns an object that specifies the name and code of the food's food group (eg. Breads, Vegetables, etc).

Each NutritionFact object has these important methods:

1. #value: How much of this nutrient is present in 1 gram of the food.
2. #units: The unit associated with #value.
3. #description: A textual description of the nutrient.

ActiveNutrition.search("olive oil").first.nutrition_facts

Calling #nutrition_facts on a Food object actually returns an instance of NutritionFacts, which provides a handy #to_hash convenience method to hash nutrient amounts by description:

# { "Protein" => 0.0, "Total lipid (fat)" => 100.0, ... }
ActiveNutrition.search("olive oil").first.nutrition_facts.to_hash

The #to_hash method is capable of hashing nutrient amounts by any method supported by NutritionFact via the :by option:

# { 203 => 0.0, 204 => 100.0, 205 => 0.0, 207 => 0.0, ... }
ActiveNutrition.search("olive oil").first.nutrition_facts.to_hash(:by => :nutrition_number)

Each Weight object offers these methods:

1. #amount: The amount associated with #measurement, eg. 1, 0.5, etc.
2. #measurement: The unit associated with #amount, eg. cup, tablespoon, gallon, dash, etc.
3. #grams: Mass in grams.

Calling #weights on a Food object actually returns an instance of Weights, which provides a handy #to_hash convenience method to hash weights (grams) by measurement:

# { "tablespoon" => 13.5, "cup" => 216.0, "tsp" => 4.5 }
ActiveNutrition.search("olive oil").first.weights.to_hash

No external requirements.

No test suite exists for this gem yet - coming soon!

Cameron C. Dutro: http://github.com/camertron

USDA Nutrition Database: http://www.ars.usda.gov/Services/docs.htm?docid=8964

Licensed under the Apache License, Version 2.0: http://www.apache.org/licenses/LICENSE-2.0

• Ability to update your local database with rake active_nutrition:update.
• Test suite.