Rhubarb Nutrition Facts and Health Benefits

Rhubarb is a tart "fruit" and is usually consumed in recipes. The perennial plant is a member of the Polygonaceae family and is widely grown outside and in hot greenhouses (hothouses).

Technically rhubarb is a vegetable, although it is generally referred to as a fruit because it is used either with fruit or interchangeably with fruit in recipes. Rhubarb pie, rhubarb crisp, rhubarb jams, and even rhubarb-flavored beverages are popular uses. But it is important that only the stalk is used when cooking. Rhubarb leaves contain toxins that are poisonous.

Rhubarb can be a healthy addition to your diet because it is naturally low in sugar and high in fiber. Many recipes that include rhubarb are desserts and can sometimes be high in sugar. If you are following an eating plan that monitors sugar or carbohydrates, it is important to examine recipes before preparation.

Rhubarb Nutrition Facts

The following nutrition information is provided by the USDA for one cup (122g) of diced rhubarb.

Carbs

Most of the calories in rhubarb come from complex carbohydrates. There are about 5 grams of carbohydrate in a one cup serving, nearly half (2.2 grams) of the carbohydrates come from fiber.

You'll also get 1.3 grams of naturally-occurring sugar in a cup of rhubarb. While many of us try to limit our sugar intake, sugars that occur naturally in food are better for your body than those that are added during processing (called "added sugars") because they come packaged with other important nutrients.

The glycemic load of rhubarb is low, (anything less than 10 is considered to be low) which means it won't raise your blood sugar quickly. One cup of diced rhubarb is estimated to be 2, while one medium rhubarb stalk is (just over two ounces) is estimated to be 1.

Fats

There is almost no fat in rhubarb. The small amount of fat is saturated fat (0.065g), polyunsaturated fat (0.121g), and monounsaturated fat (0.048g). You are not likely to consume enough rhubarb for the fat to have a significant impact on your daily intake.

Protein

There is a small amount of protein in rhubarb. You'll gain 1 gram of the macronutrient if you consume a full cup.

Vitamins and Minerals

Rhubarb is an excellent source of vitamin K, providing at least 40% of your daily needs if you consume a full cup. Rhubarb is also a good source of vitamin C, providing 11% of the daily value set by the Food and Drug Administration per cup. 

Other vitamins in rhubarb include vitamin A (5% of your daily needs), vitamin E, thiamin, riboflavin, niacin, and folate (2% each). There are smaller amounts of vitamin B6 and pantothenic acid.

Minerals in rhubarb include potassium and calcium (providing about 8% of your daily needs for each) and manganese (at least 10% of adults' needs). There are smaller amounts of magnesium, selenium, phosphorus, zinc, copper, and iron.

Health Benefits

Rhubarb can be a delicious addition to both sweet and savory dishes. Nutrients like fiber and vitamin K found in rhubarb may also offer certain health benefits.

May Ease Constipation

Foods with fiber help you to maintain a healthy digestive system. Fiber is known to improve fecal bulking, which means that it helps your body create stools to rid itself of waste.

Studies have also shown that improving your dietary fiber intake can increase stool frequency in people with constipation. In order for fiber to be effective, you need to increase your fluid intake. But authors of one study noted that fiber does not necessarily improve stool consistency, decrease laxative use, or ease painful defecation.

Better Heart Health

The fiber in rhubarb may also help you decrease your risk of cardiovascular disease. Diets rich in fiber may boost heart health by helping the body to maintain healthy cholesterol levels.

According to the authors of one research review, dietary fiber helps to regulate food ingestion, digestion, absorption, and metabolism which in turn helps to reduce the risk of hyperlipidemia (high concentration of fat in the blood) and hypercholesterolemia (elevated cholesterol levels). Both of these conditions are considered risk factors for cardiovascular disease.

Decreased Risk of Colon Cancer

Fiber intake and its effects on various forms of cancer have been the subject of many research studies. Colon cancer is a particular area of interest, with substantial research suggesting that a higher intake of dietary fiber is associated with a lower risk of colon cancer.

Authors of one large prospective study involving more than 76,000 participants concluded that individuals consuming the highest intake of dietary fiber have reduced risks of different types of colon cancer (specifically incident colorectal adenoma and distal colon cancer) and that this effect—particularly from cereals and fruit—may begin early in colorectal carcinogenesis.

Improved Metabolic Health

Epidemiological and clinical studies demonstrate that the intake of dietary fiber is inversely related to metabolic conditions such as obesity and type 2 diabetes.

However, even though some study authors specifically note that dietary fiber benefits include the prevention and treatment of type 2 diabetes, the American Diabetes Association cautions people to take the study results with a grain of salt. They write that many studies promoting the health benefits of fiber for those with diabetes are small and limited in scope. They also report that some studies suggest an intake of more than 50 grams of fiber per day, which is unrealistic for many people.

Stronger Bones

There is ongoing research about the impact of vitamin K on bone health, specifically on the prevention of osteoporosis. Osteoporosis is a condition characterized by porous and fragile bones. The National Institutes of Health reports that some, but not all, studies have found an association between a higher vitamin K intake and higher bone mineral density and/or lower hip fracture incidence.

Other Possible Benefits

Some people also use rhubarb medicinally to treat different conditions including:

• Cancer
• Constipation
• Fever
• Immune suppression
• Inflammation
• Microbial infection
• Ulcers

However, according to the medical experts at Memorial Sloan Kettering Cancer Center, there is not enough evidence to support these uses.

Allergies

Published reports of rhubarb allergy are rare.

Adverse Effects

When rhubarb is consumed as a food, it is likely safe. But because rhubarb has a laxative effect when taken in supplement form, it can make diarrhea worse.

The root and rhizome of rhubarb is likely safe when consumed by adults as a food, but the leaves and possibly the stems are toxic. Rhubarb leaves are known to contain oxalic acid, which can cause kidney issues.

Rhubarb also interacts with certain medications. Patients with hormone-sensitive cancers and those taking cytochrome P450 substrate drugs should avoid rhubarb. If you are taking melatonin, digoxin, cyclosporine, or methotrexate, rhubarb may not be safe. Talk to your healthcare provider before consuming rhubarb or using any herbal or medicinal products that contain rhubarb.

Lastly, rhubarb is low in carbs but it is usually consumed in recipes with a lot of sugar, so those following low sugar or low carbohydrate diets to manage a medical condition should choose recipes carefully, looking for those that are lower in added sugar.

Varieties

There are many different varieties of rhubarb, including Canada Red, Cherry Red, Mammoth Red, and Mammoth Green. If you find rhubarb at the grocery store, you may notice a difference in color between varieties. Some are redder and some are more green. The most common variety grown from seed is Victoria.

When It’s Best

Rhubarb is best in the spring and summer, specifically April through June. But you may be able to find it in the store later in the summer or earlier in the spring.

Look for firm stalks that are free from blemishes. If leaves are attached, they should not be wilted.

Storage and Food Safety

When you buy rhubarb, the leaves are almost always removed. If they are not removed, take them off immediately as they are poisonous.

If you are not going to use it within a few days, you can store unwashed rhubarb in the refrigerator for up to a week. Simply wrap it in a paper towel and store it in the crisper. If you don't plan to use it in that time, freeze your rhubarb.

The best method is flash-freezing. To do this, lay small chunks of rhubarb on a baking sheet and place in the freezer. Once the vegetable becomes frozen solid, place it into individual freezer bags in the amount that you are likely to use in a recipe. Flash freezing prevents the pieces from sticking together and forming a large chunk. Rhubarb may become mushy when thawed.

How to Prepare

It was once popular to nibble on the raw stalks of rhubarb (which seemed to grow everywhere) with sprinkles of salt. Doing the same thing with sugar is common in other places. But raw rhubarb is very bitter and hard to chew so it is not recommended.

You can stew rhubarb to consume as a dessert. Just cook diced rhubarb with a little water. Add a little cinnamon or nutmeg if desired. When it is soft, sweeten to taste with your favorite sweetener and serve with cream or sugar-free whipped cream.

You can also pickle rhubarb. Prepare it as you would other types of pickled fruit or vegetables, such as watermelon rind pickles. Pickled rhubarb makes a tart condiment.

If you are making a rich, heavy dish, adding a little cooked minced rhubarb can add a spark.