All varieties of beans belong to the category of vegetables called legumes, which include over 13,000 species that ranks as the world’s second-most important source of calories and protein, after grains. Although there are numerous varieties of beans, they are all similar in nutrition, provide a high-fiber, low-fat source of folate, iron and quality protein. Dried beans take longer to cook, but they are versatile and absorb the flavor of the dish as they cook.
Canned beans are convenient to prepare as they are already fully cooked and don’t have to be soaked overnight before use. So, though both dried beans and canned beans are similar in nutritional values, dried beans emerge as the winner as it is higher in folate, iron, and potassium. Canned beans are usually higher in sodium and sugar. Let’s look at more details to ascertain the facts.
Difference In Vitamin Content
Canned beans contain lower quantities of folate when compared to dried beans. Dried beans contain 58 percent of the daily value (DV) against just 23 percent found in canned beans. So, dried beans contain more than double the quantity of folate. Dried kidney beans that are cooked contain 19 percent of the DV for vitamin K and vitamin B-1 (thiamine) and 11 percent of the DV for vitamin B-6 per cup.
On the other hand, canned kidney beans have just 13 percent of the DV for vitamin K, 20 percent of the DV for vitamin B-1 and 9 percent of the DV for vitamin B-6 per cup. Vitamin K is essential for the human body for complete synthesis of certain proteins that are prerequisites for blood coagulation. Folate, thiamine, and vitamin B-6 are necessary for the body to convert the foods we eat into energy.
Similar In Macronutrient Values
A macronutrient is a chemical element or substance, such as potassium or protein, that is essential in relatively large amounts to the growth, energy, and health of an organism. Based on the nutrient, these substances are required in small amounts or large quantities. Those that are needed in large amounts are called macronutrients.
The macronutrient content of the canned beans is quite similar to that of dried beans that are cooked. One cup of cooked kidney beans contains 225 calories, 15.3 grams of protein, 0.9 gram of fat and 40.4 grams of carbohydrates. It also has 11.4 grams of fiber, which amounts to 45 percent of the daily value. In comparison, canned kidney beans contain 210 calories, 13.4 grams of protein, 1.5 grams of fat and 37.1 grams of carbohydrates. However, the fiber content is slightly high with 13.6 grams. So, in terms of macronutrient content, the two are similar.
Variation In Mineral Content
Dried beans have higher levels of minerals when compared to canned beans. A single cup of dried kidney beans that are boiled has 19 percent of the DV for magnesium, 19 percent of the DV for copper, 22 percent of the DV for iron, 20 percent of the DV for potassium, 12 percent of the DV for zinc, 24 percent of the DV for phosphorus, and 38 percent of the DV for manganese.
In comparison, canned kidney beans contain 23 percent of the DV for phosphorus, 22 percent of the DV for manganese, 17 percent of the DV for iron, magnesium, potassium, and copper, and just 8 percent of the DV for zinc per cup. Iron and copper are crucial for the body to form red blood cells. Magnesium and potassium are important as they promote muscle and nerve function. The body requires phosphorus and zinc to form DNA, and manganese to promote blood coagulation.
Disparity In Sodium Content
Most foods that are processed into cans are considerably higher in sodium to help preserve the product and increase shelf life. The American dietary guidelines of 2010 recommend consuming less than 2300 milligrams of sodium per day. Adults above the age of 50, African-Americans and people suffering from diabetes, hypertension or chronic kidney disease must avoid consuming more than 1,500 milligrams of sodium per day.
A 3.5-ounce serving of unsalted, boiled red kidney beans has 2 milligrams of sodium or less than 1 percent of the nutrient’s DV. The same amount of drained, canned red kidney beans supplies 231 milligrams of sodium or nearly 10 percent of the daily value. That is a huge difference in the sodium levels amounting to a 10-fold increase in sodium in canned beans.
Rinsing canned red kidney beans under running tap water reduces their sodium content by roughly 10 percent per 3.5-ounce serving. The American Dietetic Association Complete Food and Nutrition Guide mentions that thoroughly rinsing canned beans reduces their sodium content by as much as 45 percent.1
The table below provides the details of the difference in nutritional value between dry red kidney beans and canned red kidney beans.
|Nutritional Value||Boiled (Dry) Red Kidney Beans||(Drained) Canned Red Kidney Beans|
|Protein||8.7 grams||8 grams|
|Fat||0.5 grams||1 gram|
|Carbohydrates||22.8 grams||21.5 grams|
|Fiber||7.4 grams||5.5 grams|
|Sugar||Less than 0.5 grams||3.8 grams|
|Folate||32% of daily values||7% of daily values|
|Iron||16% of daily values||8% of daily values|
|Potassium||11% of daily values||8% of daily values|
|↑1||Duyff, Roberta Larson. American dietetic association complete food and nutrition guide. Houghton Mifflin Harcourt, 2012.|