Shea extract may help stall the progression of osteoarthritis, according to a new study. The study tested the effects of a compound sourced from the seed of the African shea tree (or Vitellaria paradoxa). Shea tree seeds are also used in the production of shea butter, a natural substance sometimes used to heal dry skin, eczema, psoriasis, burns, and rashes.

For the study, researchers assigned 89 patients with osteoarthritis of the knee or hip to 15 weeks of treatment with shea extract or a placebo. Study results showed that those treated with shea extract experienced greater decreases in inflammation (compared to study members assigned to the placebo). What's more, the shea group showed a 28.7 percent reduction in degradation of cartilage, while the placebo group had a 17.6 increase in cartilage breakdown.

In past studies, supplements containing glucosamine have also been found to fight osteoarthritis.

New research shows that buckthorn oil may help relieve symptoms of dry eye syndrome. A shrub native to Europe and Asia, sea buckthorn produces berries rich in essential fatty acids and antioxidants.

For the study, researchers recruited 100 adults with symptoms of dry eye syndrome, a condition that occurs when the eyes don't produce enough to tears to stay properly lubricated. For three months, participants took two grams of sea buckthorn oil or a placebo each day. By the study's end, those who'd taken sea buckthorn oil showed a reduction in several dry eye symptoms (including redness and burning).

Past research suggests that increasing intake of essential fatty acids (including eicosapentaenoic acid and docosahexaenoic acid) may help ease dry eye symptoms. Available in supplement form, docosahexaenoic acid is abundant in oily fish like salmon and mackerel. Also available in supplement form, eicosapentaenoic acid occurs naturally in flaxseed oil.

Preliminary research suggests that antioxidants found in blueberries may help stop the spread of breast cancer. In test-tube research, scientists discovered that anthocyanins (antioxidants pigments abundant in blueberries) helped hinder the proliferation of breast cancer cells. However, it's too soon to tell whether increasing anthocyanin intake could have the same effect in humans.

Anthocyanins are found in many other fruits, including bilberry, tart cherries, and elderberry. To boost your anthocyanin intake, make fresh or frozen berries a regular part of your diet.

Previously published lab research shows that other natural remedies may also help protect against breast cancer. For instance, resveratrol (an antioxidant found in the skin of grapes) may stop estrogen from reacting with DNA molecules and forming compounds that mark the start of cancer cell formation. A formula of green tea and the medicinal mushroom ganoderma, meanwhile, may help slow the growth of breast cancer cells.

New research shows that Pycnogenol (an extract of the French maritime pine tree) may offer natural relief of allergies. Often marketed as a supplement for heart and circulatory health, Pycnogenol appears to ease symptoms of hay fever.

For their study, researchers recruited 60 adults with birch pollen allergies. Throughout allergy season, participants took either 50 mg of Pycnogenol or placebo twice daily. Study results showed that those in Pycnogenol group had less severe allergy symptoms (compared to those who took the placebo). Pycnogenol may be most effective when taken starting five weeks prior to allergy season, according to the study's authors.

Previous research suggests that a number of other natural remedies (including omega-3 fatty acids, nettle, and quercetin) may also help fight hay fever symptoms.