Brenda Spriggs, MD, MPH, MBA
Chia seeds are primarily used to reduce the risk of cardiovascular disease. The essential fatty acids, antioxidants and dietary fiber in this herbal supplement have shown promise in reducing systolic blood pressure and preventing the onset of high cholesterol, effects that may improve your overall cardiovascular health. Evidence of other benefits is limited, but studies suggest the oil of these seeds has anti-cancer properties, according to the Memorial Sloan-Kettering Cancer Center. Consult a doctor before taking chia seeds to treat or prevent cancer, as well as any other medical condition.
A study published in the July 2007 issue of “Prostaglandins, Leukotrienes and Essential Fatty Acids,” the official journal of the International Society for the Study of Fatty Acids and Lipids, found that the oil from chia seeds could supply anti-cancer properties, in this case when it comes to the glandular tissue of the breast. The oil appears to reduce tumor growth and metastasis by inhibiting mitosis, which is the replication of cancer cells. This study, however, focused on mice, so further research is needed to determine if chia seed oil has similar effects in humans.
The oil of chia seeds is also rich in alpha-linolenic acid, which may be problematic if you're at risk of prostate cancer. A study published in the “Journal of Nutrition” in April 2004 explains that high dietary intake of alpha-linolenic acid could increase the risk of prostate cancer in men. The same is true for blood levels high in this essential fatty acid. It appears that alpha-linolenic acid plays a role in carcinogenesis, which is loosely defined as the initiation of cancer formation.
The U.S. Food and Drug Administration does not regulate chia seeds and similar substances in the same way as it does medications. It’s currently seen as a dietary supplement, so no standardized doses exist, and the recommended amount can vary from product to product. The amount of alpha-linolenic acid, polyunsaturated fatty acid, antioxidants and other nutrients in the supplement can vary as well.
As with many supplements, chia seeds have the potential of causing side effects. Most side effects, however, involve interactions with prescription medications. Taking chia seeds can increase the efficacy of anti-hypertensive and anti-diabetic medications prescribed to you, warns the Memorial Sloan-Kettering Cancer Center. The polyunsaturated fatty acids in chia seeds can also reduce clotting factors and increase the risk of bleeding, mainly when you take the supplement in high doses. Talk to a doctor before using chia seeds for any purpose.