BILBERRY Overview Information
Bilberry is a plant. The dried, ripe fruit and leaves are used to make medicine.
Bilberry is used for improving eyesight, including night vision. In fact, during World War II, British pilots in the Royal Air Force ate bilberry jam to improve their night vision, but later research showed it probably didn’t help. Bilberry is also used for treating eye conditions such as cataracts and disorders of the retina. There is some evidence that bilberry may help retinal disorders.
Some people use bilberry for conditions of the heart and blood vessels including hardening of the arteries (atherosclerosis), varicose veins, decreased blood flow in the veins, and chest pain.
Bilberry is also used for chronic fatigue syndrome (CFS), hemorrhoids, diabetes, osteoarthritis, gout, skin infections, gastrointestinal (GI) disorders, kidney disease, and urinary tract infections (UTIs).
It is sometimes applied directly to the inside of the mouth for mild mouth and throat soreness.
How does it work?
Bilberry contains chemicals called tannins that can help improve diarrhea, as well as mouth and throat irritation, by reducing swelling (inflammation). There is some evidence that the chemicals found in bilberry leaves can help lower blood sugar and cholesterol levels. Some researchers think that chemicals called flavonoids in bilberry leaf might also improve circulation in people with diabetes. Circulation problems can harm the retina of the eye.
Possibly Effective for:
- Circulation problems (chronic venous insufficiency). Early research suggests that taking bilberry extract that contains 173 mg of certain chemicals, called anthocyanins, daily for 30 days reduces symptoms associated with a circulation problem called chronic venous insufficiency (CVI). Other research suggests that taking 100-480 mg of bilberry anthocyanins daily for up to 6 months might improve swelling, pain, bruising, and burning associated with CVI.
- Problems with the retina of the eye in people with diabetes or high blood pressure (retinopathy). Eating bilberry fruit containing a high amount of a certain chemical, called anthocyanoside, seems to improve retina problems associated with diabetes or high blood pressure.
Possibly Ineffective for:
- Improving night vision. There is contradictory evidence about the effectiveness of bilberry for improving night vision. However, most evidence to date suggests that bilberry is not effective for improving night vision.
- Painful menstruation (dysmenorrhea). Early research suggests that a specific bilberry product (Tegens), taken twice daily 3 days before the beginning of the period and continuing for 8 days for a least two consecutive menstrual cycles, reduces pain, nausea, vomiting and headache in women with painful menstruation.
- Eye strain. Early research suggests that taking a combination of fish oil, lutein, and bilberry extract daily for 4 weeks reduces dry eye, lower back pain, shoulder stiffness, and stuffy head in people with eye strain.
- Glaucoma. Early research suggests that taking 60 mg of a bilberry chemical, called anthocyanin, twice daily for at least 12 months improves vision in people with glaucoma.
- Prediabetes. Some research suggest that eating a diet high in whole grains, fatty fish, and bilberries three times daily for 12 weeks reduces blood sugar in people with prediabetes. However, it is not clear if bilberry or other parts of this diet cause the reduction in blood sugar.
- High pressure in the eye. Early research suggest that taking a specific product containing 80 mg of bilberry extract (Mirtogenol) and 40 mg of French maritime pine bark extract (Pycnogenol) twice daily for 6 months can reduce eye pressure and improve blood flow to the eye in people with high pressure in the eye.
- Irritable bowel syndrome (IBS). Early research suggests that consuming a combination of agrimony, cinnamon, bilberry fruit, and slippery elm bark slightly increases the number of bowel movements and reduces stomach pain, bloating, and flatulence in people with IBS.
- Metabolic syndrome. Some evidence suggests that eating 400 grams of fresh bilberries daily does not affect body weight, blood sugar, or cholesterol in people with metabolic syndrome.
- Weight loss. Early research suggests that eating 100 grams of frozen, whole bilberries daily for 33-35 days decreases weight and waist circumference in overweight and obese women.
- Chest pain (angina).
- Varicose veins.
- Hardening of the arteries (atherosclerosis).
- Arthritis (osteoarthritis).
- Skin problems.
- Urinary tract problems.
- Chronic fatigue syndrome.
- Other conditions.
BILBERRY Side Effects & Safety
The dried, ripe fruit of bilberry is LIKELY SAFE for most people when eaten in typical food amounts.
Bilberry fruit extracts are POSSIBLY SAFE when taken by mouth for medicinal uses for up to one year. Also, a specific combination product (Mirtogenol) containing bilberry and French maritime pine bark (Pycnogenol) has been used safely for up to 6 months.
Bilberry leaf is POSSIBLY UNSAFE for most people when taken in high doses or for a long time.
Special Precautions & Warnings:Pregnancy or breast-feeding: Not enough is known about the use of bilberry during pregnancy and breast-feeding. Stay on the safe side and avoid use.
Diabetes. Bilberry leaf might lower blood sugar. Taking bilberry leaves along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely.
Surgery: Bilberry might affect blood glucose levels. This could interfere with blood sugar control during and after surgery. Stop taking bilberry at least two weeks before a scheduled surgery.
Moderate Interaction Be cautious with this combination
- Medications for diabetes (Antidiabetes drugs) interacts with BILBERRY
Bilberry leaves might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking bilberry leaves along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.
Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.
- Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with BILBERRY
There is some concern that bilberry might slow blood clotting. Taking bilberry along with medications that also slow clotting might increase the chances of bruising and bleeding. However, there is not enough information to know if this is a serious concern.
Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.
The following doses have been studied in scientific research:
- The typical dose of the dried, ripe berries: 20-60 grams daily. People also drink a type of tea made from 5-10 grams (1-2 teaspoons) of the mashed berries.
- A dose of 160 mg of bilberry extract taken twice daily has been used in people with diseased retinas.
- Bilberry leaf is commonly used as a tea. The tea is prepared by steeping 1 gram, 1-2 teaspoons, finely chopped dried leaf in 150 mL boiling water for 5-10 minutes, and then straining. Don’t use bilberry leaf long-term.