Rediscovering ʻUala

ʻUala (sweet potato) was one of the most important crops for Native Hawaiians. It is believed to have come from South America via the Marquesas, arriving in Hawaiʻi with the first migration of Polynesians. Compared to the 40-50 varieties of ʻuala cultivated in Hawaiʻi in the 1930s, only about two dozen exist today.

ʻUala was considered both a staple and famine food, as it was easily grown in dry areas with a quicker harvest than kalo. Since cultivating ʻuala wasn’t considered kapu (taboo) to wāhine as kalo was, it could be planted and harvested during periods of war when many of the kāne were away.

Besides food, ʻuala was also used in traditional medicines. It was often added to tonics to make the taste more pleasant. It was used in purgatives, which were done to help the body respond better to treatment. New mothers were provided with pounded sweet potatoes to rebuild their strength and milk supply. Young ʻuala leaves were eaten to reduce bloating. Today, ʻuala is used to treat asthma, as it can help break down mucus in the lungs. It also helps relieve constipation.

After cooking in the imu, ʻuala was typically eaten whole. However, when kalo was in short supply, it was also mashed to make poi. ʻUala leaves were wrapped in ti-leaves and cooked in the imu before eating. Some fishermen would eat preserved tubers that were baked and air-dried when their journeys took them away for an extended time. Mashed ʻuala was included as a first food for babies.

Sweet potato tubers are a good source of potassium, and helpful in lowering blood pressure. Those with yellow flesh contain beta-carotene, good for keeping your eyes and skin healthy. Purple ones contain anthocyanins, helpful for reducing the risk of heart disease and dementia. The leaves are rich in key nutrients that boost the immune system, including iron, calcium, magnesium, zinc, B vitamins, and vitamins A, C, and K.

Much of the research on sweet potatoes has studied their effect on cancer and diabetes. Chemicals in ʻuala have been shown to prevent or slow cancer growth and to kill cancerous cells – particularly those in the colon, breast, prostate, stomach, and pancreas. With diabetes, it has been shown to help the body produce the insulin and other enzymes needed to lower glucose levels.

Steaming or baking ʻuala is preferred to boiling, as this method preserves the nutrients. However, some prefer the moister texture of boiled sweet potatoes. Cooked tubers can be used to make mashed potatoes, potato salad, or kōʻelepālau, a great holiday dessert (see the enclosed recipe).

Raw ʻuala can be cut into chunks and included in laulau, stews, and soups. The leaves can be stir-fried, steamed, or added to soups and omelets. The leaves are edible raw, but the taste is bitter. They can be added to smoothies or mixed with other salad greens to make them more palatable.