Starting off your day with orange juice might actually keep the doctor away, research suggests.
Packed with vitamin C and antioxidants, orange juice is lauded for its immune-boosting properties that ward off pesky winter viruses.
But a growing body of research suggests a glass or two of orange juice a day may have long-term benefits beyond flu season.
In one recent study, researchers found that people who drank two cups of 100 percent orange juice every day had significant changes in genes related to faster metabolism, better blood vessel function and lower inflammation.
People who carried more weight also saw greater improvements in how their bodies processed fat after drinking orange juice, which could result in weight loss.
Additional studies have shown similar benefits, including lower blood pressure, putting regular orange juice drinkers at a reduced risk of heart disease.
Experts believe antioxidants in the juice called flavonoids may help trigger differences in genes related to inflammation and heart function.
However, they emphasize that not all juices are created equal. Orange juice blends with added sugar have consistently been linked to a greater risk of heart disease, as they lead to blood sugar spikes and inflammation in the heart and blood vessels.
Recent studies show drinking orange juice once or twice a day may reduce cholesterol, blood pressure and excess weight
One hundred percent juice, meanwhile, only contains naturally occurring sugar and has no additional additives or preservatives.
In one recent study, published last year in the journal Molecular Nutrition & Food Research, researchers divided 20 participants evenly into two groups: 10 normal-weight and 10 overweight adults.
Before the study began, participants gave a blood sample after fasting. Researchers isolated a group of white blood cells called peripheral blood mononuclear cells (PBMCs), which include immune system cells, such as lymphocytes and monocytes.
Every participant drank 17oz, or two cups, of pasteurized 100 percent orange juice each day for 60 days.
After two months, another fasting blood sample was collected so researchers could see whether drinking orange juice had changed the activity of certain genes.
Researchers found that the activity of 1,705 genes had changed significantly – 1,673 became less active, while 32 became more active.
Several genes involved in inflammation became less active after participants drank orange juice daily, including one linked to the production of the inflammatory protein IL-1β.
Researchers also found changes in genes involved in systems that control blood pressure, finding reductions specifically in NAMPT, NLRP3, NR4A2 and SGK1 – all which have previously been associated with high blood pressure.
Orange juice also affected genes linked to how the body stores fat. Several genes involved in the formation of fat cells, including some previously linked to obesity, became less active, including KLF4, RIPK1, PLIN2 and CXCL8.
Previous studies have found similar benefits related to heart health.
In one 2020 review, researchers found regular orange juice consumption was associated with lower blood sugar and insulin levels, reducing the risk of type 2 diabetes.
Similarly, a 2021 meta-analysis looking at 639 participants found that orange juice consumption lowered cholesterol, which is directly linked to heart disease risk, and insulin resistance, a precursor to type 2 diabetes.
And a meta-analysis in the journal Food & Function found that overweight and obese adults had reductions in blood pressure and increases in HDL (good) cholesterol after several weeks of drinking orange juice regularly.
These benefits may be due to structural changes in blood vessels. One recent study of 68 obese participants found that daily orange juice consumption improved endothelial function, or function of the lining of the blood vessels.
Better endothelial function means the blood vessels are able to more easily relax and widen, lowering the risk of heart attacks.
Researchers caution that before adding orange juice to your breakfast rotation, make sure you’re only picking up 100 percent fruit juice, as other varieties can include more added sugar than a Krispy Kreme donut or a chocolate chip cookie.
