Page Banner

United States Department of Agriculture

Agricultural Research Service

Unexpected Sources of Mineral Nutrition
headline bar

Curtiss D. Hunt

I have a suggestion that is bound to take the monotony out of grocery shopping and put more nutrition into family meals. We know that eating the right amounts of vitamins and minerals is vital to the growth of children and maintaining the health of adults. We also know that foods are not equal in terms of nutrient content. There is a lot more calcium in an ounce of whole milk than there is in an ounce of spring water. Peanut butter contains about 22 times more magnesium than does the same amount of beer. And beef chuck roast contains 22 times more zinc per ounce than does whole milk.

Shoppers would be wise to pay more attention to the total nutrient content of their diet. Very seldom, does a fellow shopper stop their cart, gaze into the distance, and whisper "Gee, my toddler gets more of her daily zinc from foods like whole milk than from foods like roast beef." Or, "Beer is the second major source of magnesium for my 30 year-old son-in-law? Or, "Foods like milk chocolate candy are the third highest source of copper for my teenage girl!"

Such nutritionally-transfixed shoppers have already logged onto the website published by USDA’s Nutrient Data Laboratory that lists the nutrient content of hundreds of foods ( This is an easy thing to do. Simply type in key words that describe your favorite food (for example, "chocolate") and hit "return." The search engine will scan the nutrient database and find all foods that have your key words in the title description of the food. Next, click on a food to proceed to selection of measurement units. Click "report," and voila! all available nutritional information about that food will be displayed.

These shoppers have also read a 1983 US Food and Drug Administration report (Journal of the American Dietetic Association, volume 82, page 166) that identifies 234 foods that are highly representative of the foods infants, toddlers, teenagers, adults, and seniors eat every day. It also gives the average consumption of each food. Combining the nutrient content of a food with the average consumption of that food provides a good estimate of how much a single food contributes to the total intake of a given nutrient.

Most shoppers do not have the time to figure out how much food they consume so they must remember that foods with high concentrations of a particular nutrient are not necessarily the major source of that nutrient. For example, we analyzed 234 representative foods and found that 11 were the most mineral-rich on the basis that they ranked highest in mineral density for three or more minerals: oat ring cereal, granola with raisins, peanut butter, peanuts, bran cereal with raisins, pecans, liver, biscuits, American cheese, cream substitute, and shredded wheat cereal.

Yet, for teenage girls, none of those mineral-dense foods was the primary source of three or more minerals. Instead, the foods that supplied the most mineral nutrition to this group were represented by whole milk, low fat milk, chocolate low fat milk, ground beef, white bread, dinner rolls, orange juice, french fries, pizza, and chocolate ice cream. Even so, remember that no food is nutritionally "bad" per se. The total quantity consumed of each food is what makes the difference. That is, teenage girls, and the rest of us, must strive to eat well-rounded diets to ensure adequate intakes of minerals and other nutrients and to reduce consumption of "empty" calories.

Last Modified: 10/23/2006