These small beans are native to East Asia and the Himalayan region and are more common in Japan, China, Korea, and other Asian nations than in the US. The name adzuki comes from the Japanese language, although the pronunciation often sounds like “azuki”. These beans are primarily red in color, but white, black, and mottled beans can be found. The scientific name of the beans is Vigna angularis, and they grow annually.
These beans are primarily used for sweetened dishes in Asian nations, such as in the preparation of natto in Japan. The adzuki bean is even used to make ice cream. Most people think of beans as savory, but adzuki beans are meant to be sweet.
Like most beans, adzuki beans are loaded with fiber, protein, complex carbs and beneficial plant compounds.
A 3.5-ounce portion contains:
- Calories: 128
- Protein: 7.5 grams
- Fat: Less than 1 gram
- Carbs: 25 grams
- Fiber: 7.3 grams
- Folate: 30% of the daily value (DV)
- Manganese: 29% of the DV
- Phosphorus: 17% of the DV
- Potassium: 15% of the DV
- Copper: 15% of the DV
- Magnesium: 13% of the DV
- Zinc: 12% of the DV
- Iron: 11% of the DV
- Thiamin: 8% of the DV
- Vitamin B6: 5%
- Riboflavin: 4% of the DV
- Niacin: 4% of the DV
- Pantothenic acid: 4% of the DV
- Selenium: 2% of the DV
Adzuki beans also provide good amounts of antioxidants, which are beneficial plant compounds that can protect your body against aging and diseases. Studies show that adzuki beans may contain up to 29 different types of antioxidants, making them one of the most antioxidant-rich foods available.
However, like all beans, adzuki beans also harbor anti-nutrients, which reduce your body’s ability to absorb minerals from the beans. Soaking, sprouting and fermenting the beans prior to eating them are three good ways to reduce antinutrient levels and make the beans easier to digest.
Adzuki beans may improve your digestion and gut health. They are particularly rich in soluble fiber and resistant starch. These fibers pass through your gut undigested until they reach the colon, where they serve as food for your good gut bacteria. When friendly bacteria feed on the fibers, they create short-chain fatty acids, such as butyrate, which studies link to a healthier gut and a reduced risk of colon cancer. Animal studies suggest that the high antioxidant content of the beans may reduce gut inflammation, further boosting digestion
Adzuki beans may also contribute to a lower risk of type 2 diabetes. This is due in part because they are rich in fiber, which helps improve insulin sensitivity and reduce blood sugar spikes after meals.
Test-tube and animal studies report that protein found in adzuki beans may block the action of intestinal alpha-glucosidases. Alpha-glucosidases are an enzyme needed to break down complex carbs into smaller, more easily absorbable sugars. Therefore, blocking their action may reduce blood sugar spikes like some diabetes medications. Adzuki beans are also rich in antioxidants, which experts believe may have some anti-inflammatory and anti-diabetes effects.
Some evidence suggests that compounds found in adzuki beans may increase the expression of genes which decrease hunger and increase feelings of fullness. Adzuki beans are rich in protein and fiber, two nutrients shown to reduce hunger and increase fullness, potentially leading to weight loss. In one six-week study, participants who consumed at least a 1/2 cup of legumes per day lost 6.4 additional pounds compared to those eating no legumes.
Test-tube and animal studies link adzuki bean extracts to lower blood pressure, as well as lower triglyceride, total and LDL cholesterol levels and less fat accumulation in the liver. Human studies also consistently associate the regular consumption of legumes with lower cholesterol levels and a reduced risk of heart disease. In one small study, women given adzuki bean juice for one menstrual cycle reduced their blood triglycerides by 15.4–17.9%, compared to increased levels in the control group. Randomized controlled studies report that diets rich in beans may lower risk factors for heart disease, including blood pressure, cholesterol and triglycerides.
Adzuki beans may offer some additional benefits. The most well-researched include:
- May help reduce birth defects: Adzuki beans are rich in folate, a nutrient important during pregnancy and linked to a reduced risk of neural tube defects.
- May fight cancer cells: Test-tube studies indicate that adzuki beans may be more effective than other beans at preventing the spread of cancer cells in the gut, breast, ovaries and bone marrow.
- May help you live longer: Beans are naturally low in the amino acid methionine. Diets low in methionine may be linked to an increased lifespan.
- May strengthen your bones: Frequent bean intake may help strengthen bones and reduce the risk of hip fractures.