Kidney Stone Formation Linked to Antioxidants

According to a large population-based study, lower serum levels of certain antioxidants may be involved in the development of kidney stones.

Investigators Peter A. Holoch, MD, and Chad R. Tracy, MD, of the University of Iowa in Iowa City, showed that the average levels of alpha-carotene, beta-carotene, and beta-cryptoxanthin are significantly lower in people who have experienced kidney stones. The researchers have concluded that these antioxidants could play a significant role in preventing stone formation. Consequently, the lower the level of these antioxidants the greater you are at risk for kidney stones.

Foods high in alpha-carotene include pumpkin, carrots, squash, corn meal, melons, tangerines, passion fruit, and plantains. Beta-carotene includes some similar foods as well as peppers, lettuce, kale, spinach, apricots, cherries, and pistachios. Beta-cryptoxanthin is found naturally in peppers, pumpkin, squash, persimmons, tangerines and peaches. Foods high in lutein include kale, collard greens, spinach, parsley, mustard greens, and okra. Lycopene is found in high amounts in tomatoes, guavas, watermelon, and grapefruit.

While the results of this study are interesting, stone formers must be aware that many of these foods are also high in oxalates, and oxalate intake and the body’s ability to metabolize oxalates is central to the process of stone formation. It would be wise to carefully assess each of these antioxidant containing foods by cross-referencing them with the list of foods to avoid before introducing any of these items into your diet in any sufficient quantity.

Until next time...cheers!