The Benefits of D-Limonene

D-limonene is a compound sourced from citrus-fruit peels. Sold in dietary supplement form, D-limonene is said to offer a variety of health benefits. 

In alternative medicine, some proponents claim that D-limonene can help treat or prevent cancer by killing cancer cells.

In addition, D-limonene is said to promote weight loss, as well as relieve symptoms of bronchitis and heartburn. D-limonene is also thought to reduce inflammation.

To date, very few studies have tested the health effects of D-limonene. However, some preliminary studies suggest that it may offer certain benefits. Here's a look at some key findings from the available research:

A number of preliminary studies published in the 1990s indicate that D-limonene may protect against cancer. In a research review published in Critical Reviews in Oncogenesis in 1994, for instance, researchers analyzed the available research on D-limonene and determined that it may help inhibit the growth of tumors and possibly protect against breast cancer.

More recent research on D-limonene and cancer includes a 2012 study from Human & Experimental Toxicology, in which tests on mice revealed that D-limonene may help protect against skin cancer in part by reducing inflammation and oxidative stress.

In addition, a 2012 study published in Life Sciences suggests that D-limonene may help fight colon cancer. In tests on human cells, the study's authors found that D-limonene may protect against colon cancer by inducing apoptosis (a type of programmed cell death essential for stopping the proliferation of cancer cells).

Given the lack of human clinical trials testing the anti-cancer effects of D-limonene, it's too soon to recommend D-limonene as a treatment of any type of cancer.

D-limonene may aid in the treatment of heartburn and gastroesophageal reflux (GERD), according to a research review published in Alternative Medicine Review in 2007. According to the report, D-limonene may help treat heartburn and GERD by neutralizing gastric acid and promoting normal peristalsis (the contraction of muscles in the digestive tract).

Due to a lack of research, little is known about the safety of long-term or regular use of D-limonene supplements.

It's important to keep in mind that supplements haven't been tested for safety and dietary supplements are largely unregulated. In some cases, the product may deliver doses that differ from the specified amount for each herb. In other cases, the product may be contaminated with other substances such as metals. Also, the safety of supplements in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications has not been established. Learn more about using dietary supplements safely.

Due to the limited research, it's too soon to recommend D-limonene for any condition. It's important to note that self-treating a condition with D-limonene and avoiding or delaying standard care may have serious consequences. If you're considering the use of this supplement, make sure to consult your physician first.

Although it's too soon to recommend D-limonene for cancer prevention, you can talk with your healthcare provider about other lifestyle changes and natural remedies that may help strengthen your defense against cancer. For instance, there's some evidence that maintaining optimal levels of vitamin D and increasing your intake of green tea and omega-3 fatty acids may offer some anti-cancer benefits.

In addition, some research suggests that such herbs as licorice, slippery elm, and marshmallow may provide some heartburn relief. You can also fend off heartburn by avoiding trigger foods, eating smaller portion sizes, and working to manage your stress levels.