Rhubarb

Rhubarb has been used for 3,000 years in dishes and as a medicinal remedy. Learn more about its history, biology, and health benefits.

Quick Facts
General Information
  • Common name(s)Rhubarb
  • Scientific nameRheum rhabarbarum
  • Plant typeVegetable
  • Native regionCentral Asia, East Asia
  • Main producer(s)China
  • Main Economic UseCulinary
Rhubarb

Rhubarb, a common vegetable used in cakes, tarts, and pies, has recently been gaining popularity for its potential medical uses, which include remedying diabetes and inflammation.

Medicinal and Nutritional Information

Quick Facts (Medicinal and Nutritional Information)
  • Medicinal actionHypoglycemic, Laxative
  • Key constituentsAloe emodin, rhaponticin
  • Ways to useCapsules, Hot infusions/tisanes, Food
  • Medicinal rating(2) Minorly useful plant
  • Safety rankingSafe

Health Benefits of Rhubarb

While rhubarb is more popular as a vegetable, preliminary research has revealed its has hypoglycemic and laxative properties. Rhubarb is commonly used for:

  • Managing type-II diabetes
  • Helping bowel movements

Rhubarb also has anti-inflammatory properties and is often used in Traditional Chinese Medicine (TCM) for the treatment of inflammatory diseases. Its most popular uses include:

  • Reducing fever
  • Stopping upper intestinal bleeding (ulcers)
  • Relieving headaches
  • Alleviating toothaches

In terms of nutrition, rhubarb is regarded as a low-calorie food, with a minimal fat and sugar content but a significant amount of complex carbohydrates and dietary fiber.

How It Works

Rhubarb stalk contains two main active constituents, anthraquinone  - also found in aloe vera and cascara sagrada – and glycoside rhaponticin. These components are thought to be partly responsible for the anti-inflammatory action of rhubarb.

Rhubarb's laxative effect is linked to its high fiber content as well as to the compound aloe emodin. Fiber assists stool formation in the intestine, while aloe emodin stimulates the bowels and decreases pro-inflammatory cytokine production.

Rhaponticin, one of rhubarb's phytonutrients, can help reduce blood sugar levels and improve other markers of diabetes. In addition, rhubarb's insoluble fiber can help lower low-density lipoprotein (LDL) cholesterol levels.

Rhubarb also contains large amounts of B-complex vitamins, such as vitamins B2 (riboflavin) and B9 (folate). It also offer a high concentration of vitamins A, C, and K, as well as minerals iron, copper, calcium, and potassium.

RHUBARB'S LAXATIVE EFFECT IS LINKED TO ITS HIGH FIBER CONTENT.

Rhubarb Side Effects

Rhubarb is likely safe for most people when the root is consumed as food and has been used in a number of culinary dishes. It is also possibly safe for adults taken in medicinal amounts for up to three months. Over consumption of rhubarb can aggravate existing gastrointestinal issues, such as diarrhea, upset stomach, or intestinal pain.

Cautions

  • Rhubard leaves contain oxalic acid, which is fatal in large dosages. Because of this, children should be monitored when consuming rhubarb leaves.
  • Due to its oxalic acid levels, those who have kidney stones or other kidney diseases should either avoid rhubarb or consume it in small quantities.
  • While more research needs to be conducted, rhubarb's levels of oxalic acid mean it may be unsafe for women who are pregnant or breastfeeding to consume rhubarb leaves.

How to Consume Rhubarb

Quick Facts (How to Consume)
  • Edible partsStem
  • TasteSweet

The most effective way of obtaining the health benefits from rhubarb is in medicinal forms of consumption, where the properties are more concentrated.

Remedies

Main preparations: Tinctures, extract, supplements

  • Tinctures. Sometimes added to wines, tinctures can be used to stimulate appetite and digestion in the short term.
  • Extract. To use as an extract as a laxative, one rootstock should be soaked in cold water for eight to ten hours before consumption.
  • Supplements. Supplements can be taken in the short term to relieve constipation. However, if taken for more than eight days, they can cause upset stomachs and other forms of gastrointestinal distress

Foods

Main ways: Raw, cooked

  • Raw. While it is bitter, eating raw rhubarb stacks can be used as a laxative or an astringent.
  • Cooked. While rhubarb is mostly used for culinary purposes, adding small doses of rhubarb to other dishes can stimulate bowel movement, making ideal for treating constipation. It is typically made in desserts such as pies, crisps, or tarts.

Buying

Quick Facts (Buying)
  • Where to buySupermarkets, Farmers' markets, Specialized health stores, Online herb stores

Raw rhubarb is easy to find in most grocery stores or local markets around the world, typically sold as the whole stem. Purchasing crisp, dark pink to red rhubarb is recommended, as green-stalked rhubarb can be more rubbery.

Rhubarb supplements are mainly found in specialized health stores and online retailers, though they are not very common. Often, a closely-related species is used in these supplements, not the species that is typically cultivated as a vegetable.

RHUBARB IS EASIEST TO FIND RAW AS A VEGETABLE.

Growing

Quick Facts (Growing)
  • Life cycleAnnual
  • Harvested partsStem
  • Light requirementsFull sun, Partial shade
  • SoilLoamy sand
  • Soil pH6.1 – 6.5 (Slightly acidic), 6.6 – 7.3 (Neutral)
  • Growing habitatCool temperate regions

In many ways, rhubarb plants have particular needs. Unlike many plants, rhubarb thrives in cooler temperatures. In fact, it should ideally be kept in temperatures below 41°F (5°C). However, it can still survive as long as it does not have prolonged exposure to temperatures exceeding 73°F (23°C). Rhubarb is an annual plant and should be treated with care.

Growing Guidelines

  • Grow rhubarb in recently treated manure that is free draining
  • Make sure rhubarb has full sun available so that it can thrive
  • Do not harvest rhubarb plants during their first year of growth
  • While it can be grown from a seed, it is more common to grow rhubarb from dormant crowns planted between autumn and spring
  • Space plants 75-90cm (30-36in) apart, with 30cm (12in) between rows
  • Harvested parts: Stem
  • Soil Type: Loamy sand
  • Soil: pH6.1 – 6.5 (Slightly acidic), 6.6 – 7.3 (Neutral)
  • Growing habitat: Cool temperate regions

Additional Information

Quick Facts (Additional Information)
  • Other usesCleaning, Dye

Plant Biology

  • Classification
    Rhubarb is a member of the Polygonaceae family, which has approximately 1,200 species spread out over 50 genera. It is known informally as the knotweed or smartweed family and contains many plants cultivated for their ornamental value, but it has very few herbs that are used for culinary purposes aside from rhubarb.
  • Varieties and Subspecies of Rhubarb
    Over the course of history, a number of varieties of rhubarb have been domesticated for human consumption. The characteristic that separates different varieties of rhubarb is the color of the edible stem. The deep red variety is the most popular among consumers, but red rhubarb produces low yields. Green rhubarb is much more productive.

Historical Information

Rhubarb was domesticated centuries ago, with researchers believing it was first cultivated as a food crop in China approximately 3,000 years ago. It is very likely that it was used then mainly for medicinal purposes. Rhubarb was brought to Greece from the Middle East and finally reached Europe in the 14th century. The cost of importing rhubarb from Asia to Europe made it one of the most expensive vegetables of Medieval times. Rhubarb arrived on American shores in the 1800s, appearing first in Maine and Massachusetts.

Economic Data

The economic importance of rhubarb lies within the culinary and alimentary industry. China is the world's largest producer of rhubarb, with each crown of rhubarb produced bringing in a gross revenue of $8 - $20 USD per year. Rhubarb is at an economical advantage because it is a vegetable crop that is used and marketed as a fruit, and is therefore harvestable in early summer, before the fruits have ripened.

Popular Beliefs

Like many herbs, rhubarb has experienced an evolution in uses. While it was originally used in ancient Chinese medicine, this vegetablesometimes mistaken for a fruitis used in many culinary dishes, such as strawberry rhubarb pie in the United States or consumed as spicy rhubarb in the United Kingdom.

DUE TO ITS POPULARITY IN PIES, IT IS ALSO KNOWN AS A “PIE PLANT”

Other Uses of Rhubarb

  • For cleaning. Rhubarb can act as a cleaner for pots and pans in order to remove stains.
  • For insecticide. It can also make an effective insecticide.
  • For painting. Some painters favor using rhubarb for its red pigmentation.

Bibliography

  • Medicinal Plants of the World, p. 270
  • MedlinePlus Herbs and Supplements, Rhubarb Leaves Poisoning
  • Journal of Ethnopharmacology, Aloe-emodin from rhubarb (Rheum rhabarbarum) inhibits lipopolysaccharide-induced inflammatory responses in RAW264.7 macrophages, 2014
  • On Food and Cooking: The Science and Lore of the Kitchen, p. 367
  • Medical Toxicology of Natural Substances, p. 235
  • Planta Medica, Rhaponticin from rhubarb rhizomes alleviates liver steatosis and improves blood glucose and lipid profiles in KK/Ay diabetic mice, 2009
  • Journal of the American College of Nutrition, Cholesterol lowering effects of rhubarb stalk fiber in hypercholesterolemic men, 1997
  • Royal Horticulture Society. Rhubarb. 2016. https://www.rhs.org.uk/