D-limonene: benefits, side effects, dosage, interactions

  Articles

D-Limonene is a compound derived from the peel of citrus fruits, including oranges, tangerines, limes, and grapefruits. D-Limonene, marketed as a dietary supplement, is said to have many health benefits, in part due to its ability to dissolve fats, including cholesterol . Proponents believe that D-limonene can help promote weight loss and treat or prevent certain diseases, including cancer.

D-limonene gets its name from lemon and is often used as a flavoring agent in foods. It differs from the less common type of limonene known as L-limonene, which is found in peppermint oil.

What is D-limonene used for?

Alternative health professionals have long touted the potential benefits of D-limonene, stating that it not only burns fat, but it also reduces inflammation and kills disease-causing microbes. Many of these beliefs stem from its use in industry, where D-limonene is commonly used to make hand sanitizers, perfumes, botanical pesticides, and chemical solvents.

Some of the conditions that D-limonene is believed to prevent or treat include:

Citrus essential oils rich in D-limonene are also used in aromatherapy to relieve stress.

To date, there is little conclusive evidence that D-limonene can treat any medical condition. That said, several preliminary studies have hinted at benefits that may warrant further study.

Weightloss

There is some evidence that D-limonene can promote weight loss by lowering blood sugar and lipids associated with metabolic syndrome. A 2013 study published in the European Journal of Pharmacology reported that obese mice fed a diet high on a diet supplemented with D-limonene experienced a decrease in blood glucose , total cholesterol , and "bad" LDL cholesterol , as well such as an increase in "good" HDL cholesterol .

These data suggest that D-limonene may be helpful in preventing or treating metabolic syndrome, although more research is needed to confirm this benefit and determine the dose required to be effective in humans.

Peptic ulcers

D-limonene may help reduce the risk of peptic ulcers and other inflammatory diseases of the gastrointestinal tract, suggests a 2009 study published in Chemico-Biological Interactions. The high concentrations of D-limonene in bitter orange ( C. aurantium ) essential oil served to protect the stomach lining of laboratory rats treated with high doses of alcohol and non-steroidal anti-inflammatory drugs ( NSAIDs ), the researchers said.

Contrary to popular belief, this was not due to the suppression of stomach acid, but to an increased production of gastric mucus.

Despite the positive results, it is unclear if D-limonene did this on its own or if it contributed some other essential oil component. More research is required.

Cancer

Alternative health professionals have long touted the anti-tumor properties of D-limonene. The effect is attributed to perlic acid, a substance that enters the bloodstream when the body breaks down D-limonene.

Several test tube studies have shown that D-limonene applied to cancer cells can induce apoptosis (programmed cell death). This is considered significant since this natural event that allows old cells to be replaced by new cells does not occur with cancer cells. This effect has been seen in studies involving colon cancer, skin cancer, and other common malignancies.

However, it is not clear whether taking D-limonene can provide the same benefit. A 2013 study by Cancer Prevention Research aimed to evaluate this effect by giving 43 women with breast cancer 2 grams of D-limonene daily for two to six weeks.

At the end of the study period, the breast tissue biopsy showed high concentrations of D-limonene, but little perlic acid, which is necessary to stop cancer growth. More research is needed to determine whether higher doses or longer treatment can help improve these results.

Possible side effects.

D-limonene, widely used as a food flavoring agent, is generally considered safe and has been used without incident in clinical trials for more than a year. Common side effects include indigestion and reflux.

In excessively high doses, D-limonene is known to cause hematuria (blood in the urine) .

The safety of D-limonene in children, pregnant women, and nursing mothers has not been established. As a precautionary measure, always consult your doctor before using D-limonene or any other supplement if you are pregnant or breastfeeding. Since the benefits of D-limonene for children are unknown, it is best to play it safe and avoid supplements altogether.

D-limonene can cause irritation when applied to the skin. The same goes for citrus essential oils, which are high in D-limonene. To reduce irritation, always mix essential oils with a carrier oil (such as avocado oil or sweet almond oil) if you intend to use them for massage.

Interactions

D-limonene is broken down by many liver enzymes that are used in other metabolic drugs. Because of this, D-limonene can increase or decrease the concentration of some drugs as they compete for the same enzyme, namely cytochrome P450 (CYP450).

Possible drug interactions include:

  • Blood thinners such as Coumadin (warfarin)
  • Anticonvulsants such as Tegretol (carbamazepine)
  • Antifungal medications such as Nizoral (ketoconazole)
  • Antihypertensive medications such as Cozaar (losartan)
  • Antipsychotic medications such as Orap (pimozide)
  • Atypical antidepressants such as nefazodone.
  • Benzodiazepine tranquilizers such as Halcion (triazolam)
  • H2 blockers such as tagamet (cimetidine)
  • Macrolide antibiotics such as clarithromycin and telithromycin.
  • NSAIDs such as Advil (ibuprofen) and Voltaren (diclofenac)
  • Proton pump inhibitors such as Prilosec (omeprazole)

Many of these interactions can be mitigated by dividing the dose between two and four hours. Others may need a dose adjustment or replacement.

To avoid interactions, always tell your doctor about any medications you are taking, whether prescription, over-the-counter, dietary, herbal, or recreational.

Dosage and drugs

D-limonene supplements are most often sold in softgels and are easy to find online or in supplement stores.

While there are no guidelines for the correct use of D-limonene, most manufacturers recommend a dosage of 500 to 1000 milligrams (mg) per day, with or without food.

As a general rule, never exceed the dosage indicated on the product label. There is no evidence that higher doses improve health benefits.

Most D-Limonene softgels can be safely stored at room temperature. You can also store them in the refrigerator if there is a risk of exposure to heat. Never use an expired supplement and discard soft gels that leak, become discolored, or warp.

What to look for

Since nutritional supplements are not strictly regulated in the United States, it can be difficult to determine which brands are good and which are not.

One way to do this is to select brands that have been tested by an independent certification body, such as the United States Pharmacopeia (USP), NSF International, or ConsumerLab. Certification does not mean that the supplement is safe or effective; it simply indicates that it contains the ingredients listed on the product label and in the correct amount.

Always check the product label for ingredients you may be sensitive to, including preservatives and gluten. If you are strictly vegetarian or vegan, look for softgels made with plant-based gelatin instead of animal gelatin made from beef or pork cartilage.

Related Articles
Foods to Avoid If You Have Dry Mouth From Radiation

Dry mouth (xerostomia) is a common side effect of radiation therapy for people undergoing treatment for head and neck cancer. Read more

Thyroid adenoma: Causes, Treatment, and Diagnosis

The thyroid is a small, butterfly-shaped gland in the front of your throat that produces hormones affecting a number of Read more

NSAIDs and You Thyroid Function

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most frequently taken over-the-counter medications. Due to their systemic or whole body effects, it's Read more

How Doctors Are Failing Thyroid Disease Patients

The thyroid disease community has continually mentioned the lack of support they experience and the difficulty they have navigating the Read more

LEAVE A COMMENT