context: Rosehip is part of the fruit that grows on the blossom of a wild rose called Rosa canina. This rose grows mostly in Europe and parts of Africa and Asia. Rosehips are packed full of vitamin C, E and B, and other antioxidants and minerals. They also contain a substance that fights inflammation. Rosehip powder might help lessen pain due to osteoarthritis. The supplement has been tested in many people with osteoarthritis of the hip, knee, hand, shoulder, neck, and other areas. A review of studies shows that people who took the supplement had less pain after three months compared to a placebo (dummy pill). Some doctors think rosehip might be an alternative to nonsteroidal anti-inflammatory drugs ( NSAIDs). Unlike NSAIDs, rosehip does not appear to thin the blood or cause stomach irritation and possible ulcers. More thorough research is needed, though. A few studies show that rosehip may also help people with long-term back pain and rheumatoid arthritis ( RA). However, studies on RA are conflicting. A small study shows that rosehip supplements do not affect RA pain. Fresh rosehips have more vitamin C than citrus fruits. However, a lot of that vitamin C is destroyed during drying and packaging. Many people take rosehip powder or fruit juice to try to boost their immune system and to try to treat or prevent colds. Animal studies hint that a daily drink containing about 40 grams of rosehip powder may also: Lower blood sugar levels and help treat diabetes Lower cholesterol Lower blood pressure Reverse obesity related to a high-fat diet How much rosehip you might take depends on the disease or condition you want to treat or prevent. Usually, you place 2 to 2.5 grams of rosehip powder in 150 milliliters of boiling water, and drink it as a tea. However, some studies have mixed the powder into apple juice. Rosehip also comes in a capsule form. You cannot get rosehip naturally in foods. Rosehip comes from a certain wild rose. However, rosehip may be added to some jams, jellies, and teas. Rosehip is generally considered safe when taken by mouth and used as directed. Reported side effects have included: Diarrhea Fatigue Headache Heartburn Nausea and vomiting Stomach cramps Trouble sleeping Rosehip supplements may raise your risk of certain types of kidney stones. And high doses may lead to dangerous blood clots, called deep vein thrombosis. Use caution when using this supplement if you are pregnant or breastfeeding. There are no studies to determine if such use is safe. You may not be able to safely take rosehip if you have: Glucose-6-phosphate dehydrogenase deficiency Hemochromatosis Sickle cell disease Sideroblastic anemia Thalassemia Large amounts of vitamin C can interfere with blood-thinning medicines, such as Coumadin (warfarin). Since rosehip contains vitamin C, use caution if you are taking these drugs. You should also ask your doctor if rosehip supplements are safe for you if you take: Prolixin (fluphenazine, an antipsychotic drug) Aspirin or other salicylates Estrogens Lithium Always tell your doctor about any supplements you are taking, including natural ones and those bought without a prescription. That way, your doctor can check on any potential side effects or interactions with any medications. Rosehip may also interfere with certain blood tests. Supplements are not regulated by the FDA.