The pomegranate is an ancient plant known to grow and thrive in harsh conditions. Despite its deep-rooted history – one that goes back thousands of years – the health benefits of the pomegranate fruit are still being uncovered.
David Heber, MD, founding director of the UCLA Center for Human Nutrition, and Zhaoping Li, MD, chief of the division of clinical nutrition at UCLA, both addressed the variety of health benefits offered by the pomegranate.
"It has the largest and most potent polyphenol antioxidant known,” Dr. Heber said. “And when it gets into your intestine this polyphenol is broken down to smaller molecules that enter into the bloodstream.”
Pomegrantes contain ellagitannins. Ellagitannins are bioactive polyphenols, chemical compounds found in the peel and seeds of a pomegranate. They employ anti-inflammatory effects on cells in the body.
These compounds can be absorbed as a juice when the whole pomegranate fruit is pressed.
Dr. Heber explained that when pomegranates are consumed, most of the fruit goes into the gastrointestinal tract (the passageway of the digestive system) and then into the colon. There, it is fermented into smaller substances called urolithins.
Urolithins travel all over the body and they can lead to positive outcomes such as reducing age-related decline, halting inflammation and preventing cardiac dysfunction.
Pomegranate effect on immunity, gut microbiome
Our gut hosts more than 100 trillion bacteria – some good, some bad. A healthy human body that is nourished with natural foods such as fruits and vegetables can promote a healthy gut, also known as the microbiome.
A 2017 study out of UCLA showed that mice consuming pomegranate extract in their feed did not contract inflammatory bowel disease at the same rate as study mice that did not feed on pomegranate extract.
“Compounds in the pomegranate work together to keep the bacteria from growing,” Dr. Heber said.
Bad bacterial growth in the gut can lead to inflammatory bowel disease as well as nausea, vomiting, diarrhea, extreme abdominal pain and cramping.
Dr. Heber explained that the traits developed by the pomegranate plant, in order for it to survive in nature, carry over when it is consumed and enters the digestive system.
“When you think about it, plants always have to fight bacteria. They grow in soil and soil is full of good and bad bacteria. So the microbiome of the soil is something that the root of the plants have to deal with all the time,” Dr. Heber explained.
“So the pomegranates developed defensive substances that work inside of a human, as well. Our microbiome is like soil that we carry around with us and there is an interaction between our cells, our immune system and the foods we eat.”
Benefits for the skin
Dr. Li referred to a separate study in which women were asked to drink pomegranate juice for several weeks.
“We then checked the redness of their skin after exposure to UV light. UV light causes oxidation and inflammation in the skin. After 12 weeks we found that you needed a higher dose of UV to cause oxidation in the skin of those who regularly drank pomegranate juice compared to a placebo drink without the pomegranate’s antioxidants.”
“It shows that a lot of what you eat and drink ends up in the skin,” Dr. Heber said.
Dr. Li said the pomegranate juice acted as an internal sunscreen, protecting the skin from within.
“The skin benefit of pomegranates is just one component,” Dr. Li said. “The skin study is a functional measurement of your whole body’s antioxidant capacity.”
Skin oxidation occurs when oxidants exceed the capacity of the body’s antioxidant defense system. This causes oxidative stress and can lead to a breakdown in collagen fibers and skin cell function, making the body susceptible to skin diseases such as skin cancer.
Improved memory linked to pomegranate juice
Memory loss can often be a part of the aging process. Oxidation occurs in the brain and that can result in mild forgetfulness. Antioxidant-heavy foods such as pomegranates, however, can help sustain cognitive function.
A placebo-controlled study concluded that phytonutrients from pomegranate juice could reduce oxidative stress on the brain and maintain brain health, helping with memory retention.
“During this study, we measured short-term memory and long-term memory outcomes of middle-aged and older adults,” Dr. Li said. “We found that pomegranates can help with the preservation of memory.”
Other benefits of pomegranate
UCLA Health has been studying pomegranates for almost 20 years, Dr. Heber said. Research has shown pomegranates to have other advantages, such as:
- Heart health benefits
- Anti-inflammatory properties
- Anti-cancer phytonutrients (similar to those of broccoli)
- Urinary health support
- Digestive health benefits
- Elevated endurance
- A boast in antimicrobial properties that fight oral germs that cause gum disease and bad breath.
Dr. Li said pomegranates can also benefit men’s health, having been linked to alleviating erectile dysfunction due to an ability to produce nitric oxide.
She explained that nitric oxide improves the health of blood vessels and causes them to widen and increase circulation. Nitric oxide is responsible for helping blood, oxygen and nutrients flow to all parts of the body.
Pomegranate variety and consumption
Dr. Heber noted there are more than 1,100 varieties of pomegranate. However, only 50 are grown commercially around the world.
A resilient plant known to adapt in diverse climates, pomegranates grew and evolved in the mountains of Central Asia. Today, they grows in many areas of the world. Domestically, California and Arizona are the two states that produce the largest amount of pomegranates.
Some people cut the fruit open and eat the arils – the juice-filled pulp that surrounds the seeds. It’s the part of the fruit that is a high source of antioxidants and fiber.
“You can cut them open and eat the arils individually,” Dr. Heber said. “However, to get the most out of them, you want them to be squeezed and taken in liquid form, as a juice”
To learn more about pomegranates and their properties, please visit the UCLA Center for Human Nutrition.