A food group is a collection of foods that share similar nutritional properties or biological classifications. Nutrition guides typically divide foods into food groups and recommend daily servings of each group for a healthy diet. In the United States for instance, USDA has described food as being in from 4 to 11 different groups
The most common food groups
Dairy, also called milk products and sometimes categorized with milk alternatives or meat, is typically a smaller category in nutrition guides,[2][3][4] if present at all, and is sometimes listed apart from other food groups.[2][3] Examples of dairy products include milk, butter, ghee, yogurt, cheese, cream and ice cream. The categorization of dairy as a food group with recommended daily servings has been criticized by, for example, the Harvard School of Public Health who point out that "research has shown little benefit, and considerable potential for harm, of such high dairy intakes. Moderate consumption of milk or other dairy products—one to two servings a day—is fine, and likely has some benefits for children. But it’s not essential for adults, for a host of reasons."[5]
Fruits, sometimes categorized with vegetables, include apples, oranges, bananas, berries and lemons. Fruits contain carbohydrates, mostly in the form of sugar as well as important vitamins and minerals.
Grains, beans and legumes, sometimes categorized as cereals, is often the largest category in nutrition guides.[2][3][4] Examples include wheat, rice, oats, barley, bread and pasta. An example of beans would be baked beans and soy beans, while an example of legumes would be lentils and chickpeas. Grains are a good source of starch and are often categorized with other starchy food such as potatoes.
Meat, sometimes labelled protein and occasionally inclusive of legumes and beans, eggs, meat analogues and/or dairy, is typically a medium- to smaller-sized category in nutrition guides.[2][3][4] Examples include chicken, fish, turkey, pork and beef.
Confections, also called sugary foods and sometimes categorized with fats and oils, is typically a very small category in nutrition guides, if present at all, and is sometimes listed apart from other food groups.[2][3] Examples include candy, soft drinks, and chocolate.
Vegetables, sometimes categorized with fruit and occasionally inclusive of legumes, is typically a large category second only to grains, or sometimes equal or superior to grains, in nutrition guides.[2][3][4] Examples include spinach, carrots, onions, and broccoli.
Water is treated in very different ways by different food guides. Some exclude the category,[4] others list it separately from other food groups,[2] and yet others make it the center[6] or foundation[7] of the guide. Water is sometimes categorized with tea, fruit juice, vegetable juice and even soup,[8] and is typically recommended in plentiful amounts.