Commonly recommend for sufferers of arthritis or other skeletal disorders, glucosamine sulfate is often supplemented when the body stops making as much as it once did. Many types of glucosamine supplements, however, are made with shellfish shells, which are not tolerable for vegetarians and vegans. For these types of specialized diets, a vegetarian glucosamine is used, which is made of mineral and plant life exclusively.
According to the National Institutes of Health (NIH), store-bought supplements of glucosamine often contain not just shellfish but also cartilage from sharks. As of 2011, this latter practice has not been scientifically proven as effective for improving the health of tendons, ligaments and cartilage. Both vegetatian or animal-derived glucosamine supplements, however, are considered "likely effective" treatments by the NIH for osteoarthritis of the knees, elbows, wrists, hips or spine. Non-vegetarian glucosamine also could derive its effective ingredient from glucosamine hydrochloride, which is found in the cartilage of any animal — from cows and chickens to pigs and whales.
According to the NIH, these supplements relieve pain in the joints equally as well as nonprescription acetaminophen drugs like Tylenol® and anti-inflammatory medicines like ibuprofen. Not everyone experiences benefits though. As a pain reliever, animal-based or vegetarian glucosamine may not be as effective since it can take as long as two months before improvements are noticed, whereas other pain medications can show relief within a few weeks. The NIH does state that glucosamine supplementation could also be possibly effective for improving symptoms of temporomandibular joint arthritis, or stiffening of the jaw. Other uses of the drug, for weight loss or to improve glaucoma, have not been proven effective as of 2011.
Vegan or vegetarian glucosamine derives its effective ingredient from plant-based sources like soybeans or vegetables, or even from natural minerals like sulfer, which is needed for glucosamine hydrochloride to become glucosamine sulfate. It is also valuable for those with an allergy to shellfish. Common ingredients of vegetarian glucosamine include various types of cellulose, stearic acid, vegetable stearate, sulfur and sodium.
Dosages of vegetarian glucosamine are similar to those for animal-based supplements. About 3,000 mg of active glucosamine sulfate is recommended daily. Some blends also add essential oils to their supplements, from vegetables like avocados or soybeans. It is unclear whether this latter practice adds to the effectiveness of the product. In total, these products claim to lubricate joints and improve joint function as much as animal-based glucosamine.