Orange Peels Emerge as Potential Cardiac Superfood

By George Citroner

Researchers may have uncovered a health secret hiding in plain sight.

The orange peel most people mindlessly toss in the trash after squeezing out the juice packs a powerful punch when it comes to combating cardiovascular disease risk factors, a new study suggests.

Reduces Levels of Compound Linked to Heart Risk

In a study published in the Journal of Agricultural and Food Chemistry, scientists examined the effects of an orange extract on compounds linked to heart disease, suggesting that orange peels may be repurposed as a natural health supplement or food ingredient.

Trimethylamine N-oxide (TMAO), a compound linked to an increased risk of cardiovascular disease, can build up in the body, and too much of it can increase the risk of heart problems. But the extract from orange peels can reduce the amount of TMAO that gets produced.

Trimethylamine (TMA), another compound linked to higher risk of heart problems and produced when the body digests red meat, is made by tiny organisms called gut microbiota that live in the stomach. The orange peel extract makes it harder for these microbiota to produce TMA.

The researchers tested the production of TMAO and TMA using two types of extracts: polar and non-polar fractions. (The polar fraction includes anything that dissolves in the water or vinegar part of the mixture, while the non-polar fraction includes anything that dissolves in the oil part of the mixture and stays away from the water.)

The non-polar fraction effectively reduced TMAO and TMA production, while the polar fraction contained feruloylputrescine, a compound that significantly inhibited the enzyme needed for TMA production.

Foundation for New ‘Functional Foods’

The discovery is significant because millions of tons of oranges are produced annually, with most peels discarded as waste. The U.S. Food and Drug Administration (FDA) considers natural orange peel extracts safe for human consumption.

Orange peels can be repurposed into valuable health-promoting ingredients, according to Ms. Wang. “Our research paves the way for developing functional foods enriched with these bioactive compounds, providing new therapeutic strategies for heart health,” she said in a press release.

The research also sheds new light on the previously unrecognized health potential of feruloylputrescine, the compound found in the extract’s polar fraction. Some research suggests that feruloylputrescine may play a role in heart health due to its antioxidant and anti-inflammatory properties.

The University of Florida’s Citrus Research and Education Center is already exploring ways to develop functional foods enriched with these bioactive compounds, which will provide new opportunities for heart health research.

The Benefits of Orange Peels

Orange peels are nutrient-dense and rich in antioxidants, vitamins, minerals, and fiber.

They contain phytochemicals that protect cells from damage, reduce inflammation, and defend against DNA damage, Stephanie Schiff, a registered dietitian and nutritionist at Huntington Hospital in New York, part of Northwell Health, told The Epoch Times.

Orange peels contain antioxidant vitamins C, A, and E. They also provide calcium, potassium, folate, magnesium, and fiber, which contribute to overall health, she noted. They contain four times more soluble and insoluble fiber than the fruit itself, according to Ms. Schiff.

These vibrant skins may help regulate blood sugar levels, reduce cancer and Parkinson’s disease risk, and boast anti-inflammatory properties due to limonene, a naturally occurring chemical studied for its anti-inflammatory properties and potential to reduce skin cancer risk.

People can incorporate orange peels into their diet in various ways.

“You can dry out your orange strips in the sun or in an oven and blend them into a powder to add to shakes or smoothies,” Ms. Schiff said. “You can cut orange peel into strips and add it to fruit or vegetable salad,” she added. You can also brew them into tea.

However, she cautions against consuming excessive amounts, which may cause digestive discomfort, and suggests starting slowly.