A large international study led by scientists from the University of Reading, Harvard Medical School, the University of California Davis, and Mars, Inc., found that most people are not consuming enough flavanols, natural compounds linked to a lower risk of heart disease.

The researchers discovered that fewer than 20% of people reached the flavanol intake level associated with heart health benefits. Even many individuals who regularly ate the recommended five daily servings of fruits and vegetables failed to meet that target.

Published on June 8, 2026, in the journal Food and Function, the study analyzed dietary data from more than 30,000 people in the United Kingdom and the United States using biomarker measurements to assess flavanol intake.

Most People Fall Short on Flavanols

Dr. Javier Ottaviani, the study’s lead author, said: “Flavanols can significantly reduce the risk of dying from cardiovascular disease, but only if you consume enough of them. Most people assume that eating plenty of fruit and vegetables covers this, but what this research shows is that the specific choices you make matter far more than the total amount. Including a handful of blackberries, a whole apple or having a cup of green tea alongside your meal could make a real difference to how much of these beneficial compounds you actually consume and absorb from the diet.”

The findings suggest that simply increasing fruit and vegetable intake may not be enough. The specific foods people choose appear to play an important role in determining how many flavanols they actually consume.

Foods Highest in Heart Healthy Flavanols

Earlier research, including the COSMOS study, the largest clinical trial to examine flavanols, found that consuming 500 milligrams of flavanols per day significantly lowered the risk of death from heart disease.

The new study indicates that most people remain well below that level, even when following standard healthy eating recommendations such as the NHS Eatwell Guide.

Researchers identified the following foods as some of the richest dietary sources of flavanols per serving:

• Plums (500g, roughly one punnet): ~450mg of flavanols
• Cranberries (250g, roughly one punnet): ~300mg of flavanols
• Blackberries (200g, roughly one punnet): ~250mg of flavanols
• Green tea (one 250ml cup): ~200mg of flavanols
• Broad beans/fava beans (80g, a small handful): ~140mg of flavanols
• Cherries (400g, roughly one punnet): ~130mg of flavanols
• Apples with skin (200g, one medium apple): ~110mg of flavanols
• Strawberries (200g, roughly one punnet): ~90mg of flavanols
• Blueberries (150g, roughly one punnet): ~80mg of flavanols
• Pinto beans (40g, two tablespoons dry): ~70mg of flavanols

Could Dietary Guidelines Be Improved?

The results also raise questions about whether current nutrition recommendations could do a better job of helping people obtain beneficial compounds such as flavanols.

Professor Gunter Kuhnle of the University of Reading said: “Five-a-day is the right message, but we may need to think more carefully about which five. Different fruits and vegetables offer very different nutritional benefits beyond vitamins and minerals, and as our understanding of these compounds grows, there is a real opportunity to make dietary guidance more specific and more effective. This research is a step towards understanding what that might look like in practice.”

The researchers say the findings highlight an important point. While eating plenty of fruits and vegetables remains a cornerstone of a healthy diet, the types of produce chosen may have a significant impact on heart health benefits.

Researchers initially suspected that a supermassive black hole was powering an extraordinarily bright distant galaxy linked to the neutrino signal. Instead, observations revealed that the galaxy’s energy comes from intense star formation. The finding provides important evidence that could help explain where many of the Universe’s mysterious high-energy neutrinos originate.

Tracking One of the Universe’s Most Elusive Particles

Neutrinos are among the most puzzling particles known to science. Vast numbers of them pass through space, and even through Earth, with very little interaction with matter. Although astronomers have identified a handful of galaxies capable of producing neutrinos, those known sources are not enough to account for the large population of high-energy neutrinos detected so far.

To investigate the origin of one such particle, an international team of researchers from MITOS Science Co., LTD., National Central University, Chung Yuan Christian University, Tohoku University, Fukui University of Technology, and the National Astronomical Observatory of Japan conducted follow-up observations using ALMA and several other telescopes.

Their target was the high-energy neutrino event IC 210922A, which was detected by the IceCube Neutrino Observatory at the South Pole. The search led them to an exceptionally luminous galaxy known as JCMT0402−0424, located roughly 11 billion light-years from Earth.

The Mystery of Shadow Blaster

Previously identified neutrino-producing galaxies have typically been powered by supermassive black holes. However, when the researchers examined JCMT0402−0424, they found no evidence of the energetic emissions normally associated with such a black hole.

The galaxy is heavily veiled by dust, making it difficult to see in visible light. At submillimeter wavelengths, however, it shines intensely. Because of its hidden nature and extreme brightness at those wavelengths, the team gave it the nickname ‘Shadow Blaster.’

A Natural Telescope Reveals the Galaxy’s Core

Astronomers were able to look deep inside Shadow Blaster thanks to a fortunate alignment with another galaxy positioned between it and Earth. The foreground galaxy’s gravity bent and amplified radio waves coming from Shadow Blaster, effectively creating a natural telescope.

This gravitational lensing effect produced brighter and enlarged images that allowed ALMA to examine the distant galaxy in far greater detail.

The radio observations again showed no sign of a powerful black hole. Instead, the data pointed toward another source of energy. The gas and dust throughout the galaxy appear to be heated primarily by vigorous star formation.

Researchers also identified a dense “compact core” at the center of Shadow Blaster. Large quantities of gas and dust are packed into a region only about 1,500 light-years across. Such an extreme environment is capable of generating neutrinos.

A New Explanation for High-Energy Neutrinos

The results suggest that intense star-forming galaxies may represent an important and previously underappreciated source of high-energy neutrinos.

According to the team, compact, dust-rich starburst galaxies undergoing rapid star formation could contribute a substantial share of the high-energy neutrino background. Their analysis indicates that these galaxies may account for as much as 20% of the total population of high-energy neutrinos observed across the Universe.

If confirmed by future studies, the discovery could significantly reshape scientists’ understanding of how some of the Universe’s most elusive particles are produced.