A glass of juice might seem like an easy fruit fix, but new research suggests whole fruit is the better pick for heart health.

In the US, official dietary advice recommends 2 cups of fruit a day for a 2,000-calorie diet. An estimated 8 in 10 people are not meeting that target and are eating less than half that amount.

The 2025 to 2030 Dietary Guidelines for Americans kept the same recommended amount of fruit, but advised people to prioritise whole fruit over fruit juice where possible.

A new study published in Current Developments in Nutrition supports that shift. Researchers led by the University of North Dakota analysed the dietary habits of 371,000 participants and found the links between fruit intake and cardiovascular disease varied by how fruit was consumed.

The researchers found a noticeable association between higher whole fruit intake and better cardiovascular health. They did not find a clear and reliable pattern between 100 percent fruit juice and the same cardiovascular disease conditions.

“The definition for what constitutes a fruit serving varies throughout the world, and the inclusion or exclusion of juice is a key point of differentiation among global fruit intake guidelines,” the researchers write in the paper.

“The aim of this study was to increase epidemiological understanding of potential relationships between CVD and fruit intake frequency by type.”

After adjusting for age, income, education and smoking status, the researchers found high blood pressure, high cholesterol, coronary heart disease and heart attacks were linked to lower whole fruit intake.

For 100 percent fruit juice, the only statistically meaningful associations were between heart attacks and people drinking juice slightly more often, and between high cholesterol and drinking juice slightly less often.

The study was a single snapshot in time, so it cannot prove direct cause and effect.

“Juice may not offer the same cardioprotective benefits as whole fruit,” the researchers write.

“However, additional research using longitudinal data and focusing on the cardioprotective nature of fruit compared with juice is needed for confirmation.”

On average, fruit juice was consumed 0.3 times per day, about once every three days, while whole fruit was consumed 1.06 times per day in the study group.

The team suggested two possible reasons for the difference, though neither was confirmed. Whole fruit keeps the plant fibre removed during juicing, which may slow sugar and insulin spikes. Polyphenols also differ between whole fruit and fruit juice, and the researchers said there is mounting evidence the versions in whole fruit are better for health.

“This study did not directly measure dietary fiber consumption or polyphenol content,” the researchers write.

“The dietary fiber differences between whole fruit and juice are based on existing knowledge that most fiber is removed during the fruit juicing process.”

The researchers said past studies have suggested fruit juice is beneficial for heart health and should be taken into account.

“Additional research is warranted to examine how CVD status affects fruit intake frequency, pinpoint potential mechanisms, and identify strategies to increase fruit consumption in the United States population,” the researchers write.

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