How drinking an orange juice every day can help your heart

image source, Getty Images

caption, Many people usually drink it as part of breakfast.

- Author, David C Gaze
- Author title, The conversation*
8 minutes

Although we have been hearing for several years that fruit for breakfast is better than orange juice because this drink only contains free sugars that increase the risk of obesity, there is no lack of studies that find interesting benefits.

In particular, recent research has shown that regular consumption of orange juice can influence the activity of thousands of genes in our immune cells.

Many of these genes help control blood pressure, reduce inflammation, and regulate the way the body processes sugar, contributing to long-term improvements in heart health.

Researchers observed adults who drank 500 ml of pure pasteurized orange juice daily for two months. After 60 days, many genes linked to inflammation and high blood pressure were less active.

These include NAMPT, IL6, IL1B and NLRP3, which are normally activated when the body is under stress.

Another gene called SGK1, which affects the kidneys’ ability to retain sodium (salt), also reduced its activity.

These changes are consistent with previous findings suggesting that drinking orange juice daily may lower blood pressure in young adults.

The juice reduces inflammation and relaxes blood vessels

The finding offers a possible explanation for why orange juice has been linked to better heart health in several studies.

The new work shows that while this citrus drink increases blood sugar levels, it triggers small changes in the body’s regulatory systems that reduce inflammation and help relax blood vessels.

That makes sense when you consider that the natural compounds in oranges, particularly hesperidin, a citrus flavonoid known for its antioxidant and anti-inflammatory effects, may influence processes related to high blood pressure, cholesterol balance, and the way the body processes sugar.

The response varied depending on body size: Heavier people tended to show greater changes in genes involved in fat metabolism, while slimmer subjects showed greater effects on inflammation.

A systematic review of controlled trials involving 639 people from 15 studies found that regular consumption of orange juice reduced insulin resistance and blood cholesterol levels. Insulin resistance is a key feature of prediabetes, and high cholesterol is a proven risk factor for heart disease.

Another analysis focused on overweight and obese adults found a slight reduction in systolic blood pressure and an increase in high-density lipoprotein (HDL), often called good cholesterol, after several weeks of daily orange juice consumption.

Person prepares orange juice. — caption, The preparation is very simple.

Although these changes are modest, even small improvements in blood pressure and cholesterol can make a significant difference if sustained over years.

In addition, according to a recent study, orange juice influences the processes related to energy consumption, communication between cells and inflammation. It may also impact the gut microbiota, which is increasingly seen as important for heart health.

If we choose blood orange juice, consuming it monthly is enough to increase the number of intestinal bacteria that produce short-chain fatty acids. These compounds help maintain healthy blood pressure and reduce inflammation.

People with metabolic syndrome benefit the most. A study of 68 overweight participants showed that daily consumption of orange juice improved the function of the blood vessel lining (endothelium function), i.e. the ability of blood vessels to relax and dilate.

And that is directly linked to a lower risk of heart attack.

Some conflicting studies

Another study conducted on 129 workers at an orange juice factory in Brazil found lower blood levels of apolipoprotein B, or Apo-B, a marker that reflects the number of cholesterol-carrying particles linked to heart attack risk.

Woman reading the label of an orange juice in a supermarket. — caption, If you don’t want to prepare it, you can buy it packaged.

However, a more comprehensive analysis of blood fat concentrations found that while levels of low-density lipoprotein (LDL) – bad cholesterol – tend to decrease, other lipid measurements such as triglycerides and HDL do not fluctuate significantly.

In any case, drinking orange juice doesn’t just seem to provide sugar: Although the whole fruit is still the best option due to its fiber, a daily glass of pure orange juice could have positive health effects that compound over time.

These include relieving inflammation, promoting healthier blood flow, and improving several blood markers linked to long-term heart health.

*David C. Gaze is Professor of Chemical Pathology at the University of Westminster in the United Kingdom.