Most of us think of orange juice as a simple breakfast habit that you pour out without giving it a second thought. However, scientists have discovered that this everyday drink may do more for the body than just quench thirst.
A recent study shows that regular consumption of orange juice can affect the activity of thousands of genes within our immune cells. Many of these genes help control blood pressure, calm inflammation and manage how the body processes sugar, all of which play important roles in long-term heart health.
The study followed adults who drank 500ml of pasteurized pure orange juice per day for two months. After 60 days, many genes associated with inflammation and high blood pressure became less active.
These include NAMPT, IL6, IL1B and NLRP3, which are typically turned on when the body is under stress. Another gene called SGK1, which affects the kidneys’ ability to retain sodium (salt), also became less active.
These changes are consistent with previous research showing that drinking orange juice daily can lower blood pressure in young adults.
Previous findings suggest that drinking orange juice every day can lower blood pressure in young people (Getty/iStock)
This is noteworthy because it offers a possible explanation for why orange juice has been linked to better heart health in multiple trials. This new study shows that the drink does more than just raise blood sugar. Instead, it appears to trigger small changes in the body’s regulatory systems that reduce inflammation and help blood vessels relax.
Natural compounds in oranges, especially hesperidin (a citrus flavonoid known for its antioxidant and anti-inflammatory effects), appear to affect processes related to high blood pressure, cholesterol balance and how the body processes sugar.
Reactions also vary based on body size. Heavier people tended to show larger changes in genes related to fat metabolism, while leaner volunteers showed stronger effects on inflammation.
A systematic review of controlled trials involving 639 participants from 15 studies found that regular consumption of orange juice can reduce insulin resistance and blood cholesterol levels. Insulin resistance is a key feature of prediabetes, and high cholesterol is an established risk factor for heart disease.
Another analysis of overweight and obese adults found that drinking orange juice daily for a few weeks was associated with a slight decrease in systolic blood pressure and an increase in high-density lipoprotein (HDL), commonly known as good cholesterol. Although these changes are modest, even small improvements in blood pressure and cholesterol can produce meaningful changes if maintained over many years.
More clues come from the study of metabolites, tiny molecules produced when the body processes food. A recent review found that orange juice affects pathways related to energy use, communication between cells, and inflammation. It may also affect the gut microbiome, which is increasingly recognized to play an important role in heart health.
About the author
David C. Gaze is Senior Lecturer in Chemical Pathology at the University of Westminster.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
One study showed that drinking blood orange juice for a month increased the number of gut bacteria that produce short-chain fatty acids. These compounds help maintain healthy blood pressure and reduce inflammation. Volunteers also showed improved blood sugar control and reduced levels of inflammatory markers.
People with metabolic syndrome, a set of risk factors that include high blood pressure, elevated blood sugar and excess body fat, may experience particular benefits.
In one study, drinking orange juice daily improved the function of the lining of blood vessels, known as endothelial function, in 68 obese participants. Endothelial function describes how well blood vessels relax and dilate, and better function is associated with a lower risk of heart attack.
Not all studies report the same results. A broader analysis of blood lipid concentrations found that while levels of low-density lipoprotein (LDL), commonly known as “bad cholesterol,” often fall, other lipid measurements such as triglycerides and HDL may not change much. Even so, people who drink orange juice regularly may still benefit.
A study of 129 workers at a Brazilian orange juice factory reported low blood levels of apolipoprotein B (apo-B), a marker that reflects the number of cholesterol-carrying particles associated with heart attack risk.
Taken together, this evidence challenges the idea that drinking citrus juice simply consumes sugar in the glass. Whole fruit is still a better choice due to its fiber, but a moderate glass of pure orange juice a day seems to make a difference over time.
These include reducing inflammation, supporting healthier blood flow, and improving multiple blood markers associated with long-term heart health. It’s a reminder that our daily food has a greater impact on our bodies than we think.
