What Is Blueberry Extract?

Blueberry extract is a natural health supplement made from concentrated blueberry juice. A rich source of nutrients and antioxidants, blueberry extract contains beneficial plant compounds (including the flavonol quercetin) and anthocyanins, a class of compounds thought to reduce inflammation and protect against heart disease and cancer.

Although its benefits are unproven, it is often promoted for the following conditions:

This article reviews research on blueberry extract, side effects, and potential interactions.

Unlike drugs, dietary supplements are not regulated in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed. When possible, choose a supplement tested by a trusted third party, such as USP, ConsumerLab, or NSF. 
However, even if supplements are third-party tested, it doesn’t mean they are necessarily safe for all or effective in general. Therefore, it is important to talk to your healthcare provider about any supplements you plan to take and check in about potential interactions with other supplements or medications.

Supplement Facts

• Active ingredient(s): Blueberry
• Alternate name(s): Vaccinium angustifolium plant
• Suggested dose: No standard recommended dose
• Safety considerations: Not a lot of data on safety, interacts with some medications
  

Uses of Blueberry Extract

Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian (RD), pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent disease.

Although research on the health effects of blueberry extract is very limited, some studies suggest that blueberries may offer certain potential benefits.

Research on the potential benefits of blueberries has focused on fresh blueberries, blueberry powders, and blueberry juice or juice concentrate. The concentrated juice is used to form a blueberry extract that can then be sold in pill or capsule form. Blueberry powder is made from freeze-dried blueberries.

Preliminary research has found:

• A creatine plus blueberry extract supplement improved muscle strength and power during exercise.
  However, it did no better than a regular creatine supplement.
• A blueberry extract dosed at 100 milligrams (mg) daily for three months helped improve memory performance in older adults. Blueberry powder did not improve memory performance.

• A systematic review of cranberry and blueberry consumption concluded that both berries may have a beneficial effect on glucose control in people with diabetes. Daily cranberry juice for 12 weeks and blueberry extract or powder for 12 weeks was used in the studies reviewed.

• Another study found that six weeks of daily blueberry consumption didn't improve blood pressure.
  However, it did improve endothelial function. The inner lining of the small arteries, the endothelium, is involved in many vital bodily functions—including regulating blood pressure.

When evaluating the preliminary research, it is important to note that the studies are small, and interventions often include blueberry extract in products with several other ingredients. Additionally, some supplement companies may apply research findings on fresh blueberries or anthocyanins from other sources to market blueberry extract benefits.

There is not enough evidence to support any uses for blueberry extract at this time.

What Are the Side Effects of Blueberry Extract?

Little is known about the safety of long-term use of blueberry extract supplements. Blueberry is safe to consume in the amounts found naturally in food. However, it is unclear how much blueberry extract is safe to take.

Whole blueberries, blueberry juice, and blueberry powder are typically well-tolerated, with few side effects. However, drinks that contain freeze-dried blueberries have been reported to cause constipation, diarrhea, nausea or vomiting in some people. It is not known if blueberry leaf is safe.

Verywell / Anastasia Tretiak

Precautions

Eating blueberries is fine for most people who are pregnant or breastfeeding, but there is no data on the safety of blueberry extract. Therefore, the extract is not recommended for pregnant and lactating individuals.

Blueberry extract may have a glucose-lowering effect and interfere with glucose control during surgery. It is recommended to avoid blueberry extract at least two weeks before a scheduled surgery, as hypoglycemia (low blood sugar) may occur.

People with glucose-6-phosphate dehydrogenase deficiency (G6PD) may have difficulty digesting blueberries. If you have this disorder, you should discuss with your care provider before adding blueberry extract to your regimen.

Since blueberry extract may lower blood sugar levels, those taking diabetes medications should use caution when using this supplement.

Dosage: How Much Blueberry Extract Should I Take?

Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs. 

There is no standard dose for blueberry extract. More research is needed before determining a safe range. Should you decide to take blueberry extract supplements, follow the instructions on the supplement label.

What Happens If I Take Too Much Blueberry Extract?

There is insufficient data to suggest any ill effects if you consume too much blueberry extract.

Interactions

Blueberry extract may interact with certain medications.

Taking blueberry extract with antidiabetic medications may increase the risk of hypoglycemia as both could work to lower glucose levels. Additionally, be mindful of taking it other supplements that may also lower blood sugar, such as:

• Aloe
• Bitter melon
• Cassia cinnamon
• Chromium
• Prickly pear cactus

While not likely a major concern, blueberry juice may reduce the time it takes for the body to break down and eliminate some medications, such as buspirone and flurbiprofen.

How to Store Blueberry Extract

It is best to follow the manufacturer's guidelines for storing blueberry extract. Always store medications and supplements out of the sight and reach of children and pets.

Similar Supplements

All forms of blueberry supplementation mustn't be treated equally. Blueberries, blueberry powder, and blueberry juice extract may not have the same intended effect. They also may have different dosing suggestions.

Additionally, do not confuse blueberry and bilberry. European blueberries are often, in fact, bilberry.

Frequently Asked Questions

• Is taking blueberry extract better for you than eating whole blueberries?

  There is not enough data to suggest that a blueberry extract is better or even provides equal nourishment as whole blueberries would.
  

  Both whole blueberries and blueberry extract are an abundant source of vitamins and minerals. Depending on the formulation, blueberry extract supplements may contain a higher dose of nutrients than the whole fruit, but whether that is a good thing once it is consumed is not known.
  

  Alternatively, fiber is removed during the extraction process. Blueberries are considered a good source of fiber, with 3.6 grams in a 1 cup serving. This accounts for 14% of the recommended daily intake of fiber based on a 2,000-calorie-a-day diet. If your diet lacks fiber, whole blueberries may be a better choice for you.

• Will blueberry extract help improve cognitive function?

  There is not enough research to suggest benefit from blueberry extract. Research on blueberries and cognitive function has used fresh blueberries, blueberry powder, or blueberry juice concentrate but not blueberry extract.
  

  In a study published in Food & Function in 2017, researchers examined the cognitive effects of consuming either freeze-dried blueberry powder or a placebo (an ineffective substance) on a group of children between the ages of 7 and 10.

  Three hours after consuming the blueberry powder, participants were given a cognitive task. Participants who had taken the blueberry powder completed the task significantly faster than those in the control group.
  

  Consuming freeze-dried blueberry may also improve some aspects of cognitive function in adults. In a study published in the European Journal of Nutrition, for instance, people between age 60 and 75 consumed either freeze-dried blueberry or a placebo for 90 days. Participants completed tests on cognition, balance, and gait at the beginning and again at days 45 and 90.
  

  While both of these studies suggest benefit from freeze-dried blueberry, it should be noted this is not the same as blueberry extract.
  

• Will blueberry extract help control blood sugars in people with diabetes?

  There is not enough data to support recommending blueberry extract for people with diabetes. Preliminary studies suggest that blueberries may improve insulin resistance and glucose tolerance.
  

  A report published in Critical Reviews in Food Science and Nutrition in 2018 looked at blueberry extract and glucose control in people with diabetes. Researchers reviewed previously published clinical trials on blueberry or cranberry consumption on type 2 diabetes glycemic control.
  

  In their review, they found that using blueberry extract or powder supplementation—providing 9.1 or 9.8 milligrams (mg) of anthocyanins, respectively—for eight to 12 weeks had a beneficial effect on glucose control in people with type 2 diabetes.
  

  While this study is promising, it also preliminary, and more high-quality clinical trials are needed before routinely recommending these supplements for people with diabetes.

Sources of Blueberry Extract & What to Look For

Blueberry extract is sourced from cultivated highbush blueberries or the smaller wild lowbush blueberries. Blueberry extract comes in capsule, tincture, powder, and water-soluble extract forms. It is available for purchase at natural-foods stores, drugstores, and online.

Note that blueberry extract is not the same as blueberry leaf extract. Blueberry extract is made from the fruit of the blueberry, while the leaf extract is made from the leaves of the blueberry bush. The two have some overlapping benefits, but they are not interchangeable.

The supplement label should clarify if the extract is from fruit or leaf. Be sure to check, so you purchase what you intend to. Also make sure that you read the entire ingredients list. Many manufacturers add other vitamins, nutrients, or herbal ingredients to blueberry extract.

In addition, check the label for a trusted, independent third-party seal, such as USP (U.S. Pharmacopeia), NSF International, or ConsumerLab. This does not guarantee a product's effectiveness, but it does certify that the ingredients listed on the label are what you are getting.

Summary

Blueberries have been promoted as a superfood for years due to their nutrient profile. In addition to whole blueberries, parts of the blueberry plant are now processed into supplements and marketed for multiple conditions. While it is too soon to say conclusively that blueberry extract can prevent or treat any medical condition, the research shows that whole blueberries are a powerhouse of nutrients, including vitamins, minerals, and important antioxidants.

If you are considering supplementing with blueberry extract, talk with your healthcare provider to determine if it is right for you.