Naturally Balancing Blood Sugar with Plants

Learn about the benefits of holy basil, fenugreek and prickly pear for diabetes, as well as other helpful herbs.

By Dawn Combs


November/December 2016

Bitter Melon

Bitter melon is part of Chinese and Indian food and medicine.

Photo by iStock

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A number of plants have been used to help control non-insulin dependent (type 2) diabetes for as long as plants have been included in written history. We have come to understand that these plants help maintain healthy blood sugar levels by inhibiting the absorption of glucose following a meal; increasing the number of insulin receptors on cell walls; increasing the efficiency (sensitivity) of those insulin receptors; or simply reducing blood glucose levels. What follows is what we know today about four plants that have proved effective for supporting healthy blood sugar levels, and are also easy to grow at home.

Be advised that if you are taking pharmaceuticals to lower blood sugar, you will need to use caution when also using the garden as a medicine cabinet. Most of the plants that demonstrate hypoglycemic ability (the ability to lower blood sugar levels) are powerful enough to increase the effectiveness of prescribed medications. Whether you choose to work with the following plants in combination with medication or not, it’s always a good idea to communicate with a medical professional and test your blood sugar scrupulously.

Holy Basil (Ocimum tenuiflorum)

Holy basil is popular in Ayurvedic practice, where it is also called tulsi. Several good varieties of the plant include ‘Kapoor’, ‘Amrita’, ‘Rama’ and ‘Krishna’, as well as the species called holy basil, Ocimum gratissimum or Vana Tulsi. All of these basils are used interchangeably and are known as adaptogens, meaning they support the body’s response to stress. Holy basil has been researched extensively, and ample evidence suggests this high-antioxidant plant also supports the healthy digestion and adrenal function needed to allow the body to use glucose efficiently.

How to Grow: Holy basil grows best in full sun and all varieties except ‘Kapoor’ are annuals in temperate climates. It seems possible for ‘Kapoor’ to self-seed. Seed should be barely covered with a layer of soil and is best direct-sown after danger of frost has passed. It likes richly composted soil to start and enjoys steady moisture while getting established. Just like its more common basil cousin, Ocimum basilicum, holy basil will bush out if you pinch off the growing tips often. Eat more and the plant produces more.

How to Use: Holy basil is high in volatile oils, delicious fresh or dried, and makes an excellent tea. You will also find holy basil in capsules and tinctures. Some studies have shown good results with one to four grams of dried holy basil leaf daily.

Prickly Pear Cactus (Opuntia streptocantha and related species)

We have learned from American Indians and Mexicans how to use prickly pear cactus (also called nopales) to lower blood sugar. Modern studies have found that the plant works to reduce blood sugar levels by increasing insulin sensitivity, allowing more glucose to enter the cells, leaving less to roam freely in the blood and cause trouble. Most of the prickly pear genus is native to the American Southwest, but some varieties, such as O. humifusa and O. polyacantha, remain hardy even in Zone 3 (northern U.S. and southern Canada), where winter-hardiness is of utmost importance. Most of the Opuntias have edible pads, flowers and fruits, but only the pads are used for blood-sugar maintenance.

How to Grow: Prickly pear likes to grow in full sun and does not like to stand in waterlogged soil. It needs to dry completely between waterings (which means if you grow prickly pear indoors in a pot, you might only water it every two to three weeks). The cactus easily roots from a pad placed cut-end down in the soil. Pads are ready to harvest when they are fresh and the spines are still rubbery. 

How to Use: Fresh prickly pear pads can be eaten raw or cooked, but drying them appears to reduce medicinal effectiveness. The rubbery spines can be cut off or simply charred on the grill, and the pads can also be juiced (with spines and pulp strained out). The plant needs to be eaten in rather high amounts to match study results, but if you can grow prickly pear, it certainly doesn’t hurt to add a pad to your daily diet. Check out these simple cooking instructions.

Bitter Melon (Momordica charantia)

The vegetable bitter melon is at home in African, Chinese and Indian food and medicine. This bitter addition to foods has a long history of use in treating type 2 diabetes, lowering the amount of glucose in the blood dramatically over a period of weeks. Bitter melon also supports healthy digestion, which is important for anyone struggling with maintaining healthy blood-sugar levels. Additionally, studies confirm that a component of the plant, charantia, behaves similarly to insulin, and the use of the plant reliably increases insulin sensitivity.

How to Grow: This tropical vine can be grown like an annual, in well-composted, evenly moist soil in full to partial sun. It is best trellised, as the fruits rot easily when lying on the ground. Pick bitter melon when it’s green with just a hint of yellow. 

How to Use: Bitter melon is often used as a food. The green melons are sliced open and the seeds removed, leaving just the bitter outside flesh. For those who wish to use the plant for blood-sugar control, studies have shown that either a decoction (a medicinal tea made by boiling the plant for 20 minutes and then straining) or juicing yields the best results. Most of these studies suggest starting with 50 ml daily.

Fenugreek (Trigonella foenum-graecum)

Aromatic fenugreek has long been used to treat diabetes, and its abilities are recognized by numerous clinical trials. The seeds of this plant seem to affect fasting glucose levels, and are able to impact the amount of glucose entering the system after a meal.

How to Grow: Fenugreek is in the bean family and can be used as a cover crop, increasing the nitrogen content of the soil while you wait for its useful seeds to develop in the fall. If you have recently turned over new soil that has been heavily fertilized, you may want to add an innoculant (a helpful bacterial preparation you can buy in powder form) during seeding. Grow fenugreek in full sun in well-drained, slightly acidic soil. This traditional Indian plant is best grown indoors from seed four to six weeks before your last frost. It doesn’t care much for being transplanted, so it is best to grow it in individual pots or use a biodegradable one if you plan to later plant them outdoors.

How to Use: Dried fenugreek seeds can be chewed or cooked, though a recent study suggests that when made into a tea (as a decoction, as discussed with bitter melon), fenugreek is most effective at lowering blood sugar. You can also find fenugreek tinctured, encapsulated or even sprouted. For best results, you need to consume fenugreek seeds (or preparations made from seeds) two to three times a day.