You don’t think twice before reaching for orange juice in the fridge. Cold, sweet, vitamin C. Done. But there’s a new pasteurized orange juice study from 2025 that tells us your morning OJ is doing more than you ever knew. We’re talking about altering the function of thousands of genes.
Researchers asked 20 healthy adults to drink around two cups of pure pasteurized orange juice a day for two months. They looked at what had happened, in terms of people’s immune cells, 60 days later. The genes associated with inflammation, such as IL6, IL1B, and NLRP3, decreased. The SGK1 gene, involved in how your kidneys retain sodium, turned down as well. These factors are closely connected to blood pressure and heart health.
What Happens During Pasteurization
Does pasteurization affect orange juice? Yeah, it does. It is heating juice to kill bacteria and expand its life. The FDA makes them do it for safety after some bad outbreaks of raw juice in the early 2000s.
But heating changes stuff. About 85 to 90% of the vitamin C makes it through. That’s pretty good. The vitamin C you lose isn’t even primarily because of heat. It’s oxygen exposure during storage. That carton you cracked open last week? Not quite the same as the first pour.
Antioxidants such as flavonoids linger, too: More than 80% are still around. These are good for heart health, and they’re anti-inflammatory. So not everything gets killed by pasteurization, regardless of what your health-nut friend tells you.
Does Pasteurization Destroy Vitamin C in Orange Juice?
Not entirely. Most will survive, although it does begin to degrade after you open the container. Light, heat, and oxygen accelerate decay. Which is why sealed packaging and refrigeration are important.
Fresh-squeezed has a small advantage in nutrients just after squeezing. But unless you’re drinking that juice within hours, the processed juice found on store shelves generally has similar amounts because it is shielded from oxygen and gets packed shortly after pasteurization.
What the Research Found
The pasteurized orange juice study looked at gene expression in immune cells. After two months of daily juice, genes associated with inflammation and high blood pressure showed reduced activity. This data matches earlier research showing daily orange juice can lower blood pressure in young adults.
One review of 15 studies involving 639 people concluded that drinking regular orange juice reduced insulin resistance and bad cholesterol. Insulin resistance is basically pre-diabetes. So the benefits add up.
Another study, with overweight participants, found that a few weeks of daily juice lowered blood pressure and raised good cholesterol slightly. It doesn’t look like much, but it adds up over years.
The Magic Ingredient
It’s hesperidin, a natural flavonoid that comes from oranges. It has antioxidant and anti-inflammatory effects that influence blood pressure, cholesterol, and sugar metabolism. Hesperidin helps keep blood vessels relaxed and cholesterol levels in check.
Interestingly, heavier individuals experience more changes in genes involved in fat metabolism. Leaner individuals tend to have more robust changes in inflammation-related genes. Your body type matters.
What About All That Sugar?
Look, orange juice has sugar. One cup has about 21 grams from the fruit. That’s real. But the research shows it’s not just spiking your blood sugar and leaving you worse off.
The flavonoids and other compounds seem to offset some of the sugar impact by improving how your body processes glucose. This doesn’t mean you can chug OJ all day. But it’s not the villain it’s been made out to be.
One glass in the morning as part of a balanced diet? Probably fine for most people. Three glasses a day plus other sugary stuff? That’s pushing it.
What Are the Disadvantages of Pasteurization of Juice?
There are trade-offs. Pasteurization reduces some heat-sensitive nutrients slightly. Flavor changes too. The volatile compounds that give orange juice its aroma fade during heating, and new notes, sometimes slightly bitter, emerge.
That’s why juice never tastes exactly like fresh-squeezed. Companies use flavor packs made from orange essence to standardize taste. They’re safe but essential to making store-bought juice taste consistent.
Some people prefer unpasteurized juice for taste. But the CDC keeps warning that raw juices carry real bacterial contamination risks. Is the slight nutrient bump worth getting sick? Most experts say no.
What This Means for You
Should you start drinking orange juice daily because of this study? Depends. If you already enjoy it and don’t have blood sugar issues, the research suggests genuine benefits beyond vitamin C.
But don’t treat it like medicine. It’s still juice with natural sugars. Pair it with protein or fat to slow sugar absorption. Drink it with breakfast, not on an empty stomach.
Keep opened juice refrigerated and sealed tight. Vitamin C and flavor compounds degrade faster once exposed to air. That carton you’ve had open for two weeks isn’t doing much.
And maybe reconsider the “orange juice is bad” narrative that’s been popular lately. The research shows it’s more complicated. Yes, it has sugar. But it also has bioactive compounds that benefit your cardiovascular system in measurable ways.
The Bigger Picture
The research is part of a revolution in how we think about food. We’re moving beyond the old “good food, bad food” categories and asking how chemicals in foods interact with our biology, deep down at a genetic level.
Orange juice isn’t a superfood. But it’s not poison. It’s a drink with pluses and minuses, and the science suggests the pluses may be more significant than anyone would have believed
And a study from an orange juice factory in Brazil found that workers had lower levels of apo-B, which is a marker for cholesterol-carrying particles that raise the risk of heart attack. Regular, moderate intake appears to have protective effects with time.
The key word is moderate. One glass a day in the context of a varied diet including whole fruits and vegetables; other nutrient sources should not be excluded. Not three glasses and a bunch of other sugary drinks.
What Researchers Say
Scientists are cautiously optimistic. They’re not saying everyone should load up on orange juice. They’re saying the research challenges assumptions about how juice affects the body.
The gene expression changes are real and measurable. The cardiovascular benefits show up across multiple studies with different populations. But it’s not a reason to replace water with OJ or think you can offset a terrible diet with one healthy beverage.
More research is coming. Scientists want to understand long-term effects better and figure out optimal amounts for different populations. But current evidence suggests that for most healthy adults, a daily glass might be doing more good than harm.
Bottom Line
Your morning OJ has more to it than you thought. Yes, it’s pasteurized, which affects several aspects of the juice. But it’s still packing vitamins, antioxidants, and compounds that are good for your heart and blood pressure over the long term.
The new research about gene expression changes is fascinating. But don’t overthink it. If you enjoy orange juice and it fits within your diet without leading to blood sugar issues, there is good evidence that it’s giving you actual benefit.
Just drink that opened carton within a week instead of letting it sit for a month. And don’t replace actual medical advice or a balanced diet with juice. It’s breakfast, not a miracle cure.
But it’s nice to know that thing you’ve been drinking your whole life might actually be looking out for your cardiovascular system on a genetic level. Kind of cool, right?
