Nutrition in the Balance: The Food Pyramid
It has long been known that a healthy lifestyle is based on a balanced diet - eating foods providing good nutritional value. This is why we call some foods "junk food". They provide little of nutritional value and only serve to give energy for the moment, or bulk for the long term. In order to help the general population to know what mixture of foods constitutes a healthy lifestyle, the U.S. government came out with the four food groups in 1956. These were meat, vegetables (and fruits), dairy, and grains.
The "four food groups" served a vital purpose in educating the public on how to lead healthier lives by eating more nutritional foods. Since the 1950s there have been many advances in the study of nutrition. Nutritionists have been able to develop more helpful diet models to more specifically guide consumers in their choices of food.
The Food Pyramid
The food pyramid came out in the 1990s as a way to disseminate new information learned about the human body's nutritional needs. The food pyramid is meant as a general guideline. The chart to the left is provided by the USDA (United States Department of Agriculture). The USDA recommendations are based on the following serving sizes:
- Fats, oils, and sweets are not given a serving size because ideally they should only be consumed in very low quantities.
- 1 cup healthy yogurt or milk, 1 1/2 ounces of natural cheese or 2 ounces of process cheese, each count as one serving.
- A serving of lean meat, poultry or fish is comprised of 2-3 ounces. 1/2 cup of cooked dried beans, a single egg, and 2 tablespoons of peanut butter all count as a single ounce of lean meat (meaning it would take 4 tablespoons of peanut butter to constitute a single serving.) It should be noted that meats are important not just for the protein, but because vitamin B12 cannot be found in vegetarian substitutes such as beans and peanuts.
- A serving of vegetables would be constituted of 1 cup of raw leafy vegetables, or a 1/2 cup of some other vegetables, or 3/4 cup of vegetable juice.
- Fruits are very similar to vegetables in serving size - 1 medium apple, banana or orange, 1/2 cup of fruit (including canned), or 3/4 cup of fruit juice.
- In the general category of grains, serving sizes can be construed as, 1 slice of bread, or 1 ounce of ready-to-eat cereal, 1/2 cup of cooked cereal, rice, or pasta.
An interesting thing to note about the food pyramid is that the base of it (and the largest component of the average diet) is the grains, comprising of breads, cereals, rice and pasta. Fats and sweets seem to be on the list only because they are edible and perennially popular. Meats and dairy have a diminished role in a healthy lifestyle.
Vegetables and Fruits
It is becoming more and more apparent to nutritionists that vegetables and fruits are the focus of a nutritional diet not least because they contain anti-oxidents like lycopene. So much so that some believe that meats and dairy products, as well as oils and sweets should be left out of the food pyramid altogether. In fact a whole new system of four food groups has been developed for vegetarian diets that provides for all the basic vitamins, minerals, and fiber that a body needs. In this system the recommendations are: 3 or more servings of fruit, 2 or more servings of legumes (such as peas or beans), 5 or more servings of grains (bread, pasta, etc.), and 4 or more servings of vegetables.3
The Nitty-gritty of Nutrition
But nutrition goes deeper than general categorization of food groups; it delves deeper into such realms as biology and chemistry to help find out what constitutes a healthy diet. This means understanding the effects of specific minerals, vitamins, and enzymes, like calcium, beta-carotene, or tryptophan. By delving into processes such as the way that the body converts vitamin C into oxalic acid, nutritionists can determine the best recommendations for populations, or individuals, to live longer, healthier, and happier lives.4
- Fifties Web: Pop History
- Food Pyramid Serving Sizes and Food Pyramid Image
- PCRM: Food Groups
- Some believe resveratrol (also sometimes called reservatrol) might be a key ingredient to living longer.