Surprising research reveals why you shouldn't add bananas to your smoothies

You may not get what you want

University of California - Davis

Smoothies are one of the easiest ways to pack more fruit into your day. Toss in a banana, add some berries, blend, and you have what looks like a perfectly healthy drink. But research from the University of California, Davis suggests that this popular combination may have an unexpected downside.

The issue is not that bananas are unhealthy. Instead, it comes down to how certain ingredients interact after they are blended together. In a study published in the Royal Society of Chemistry journal Food & Function, researchers found that fruits with high levels of an enzyme called polyphenol oxidase, or PPO, can sharply reduce the amount of flavanols your body absorbs from a smoothie.

Flavanols are natural plant compounds linked to heart and cognitive health. They are found in foods such as apples, pears, blueberries, blackberries, grapes, cocoa, and other common smoothie ingredients.

The Enzyme Behind Browning Fruit

"We sought to understand, on a very practical level, how a common food and food preparation like a banana-based smoothie could affect the availability of flavanols to be absorbed after intake," said lead author Javier Ottaviani, director of the Core Laboratory of Mars Edge, which is part of Mars, Inc., and an adjunct researcher with the UC Davis Department of Nutrition.

Anyone who has sliced an apple or peeled a banana has seen PPO in action. When the fruit is cut, bruised, or exposed to air, the enzyme helps trigger the browning reaction. The UC Davis team wanted to know whether that same process could also affect the nutrients people hope to get from smoothies.

To test the idea, the researchers used freshly prepared smoothies made with ingredients that naturally contain different amounts of PPO. Bananas have high PPO activity, while mixed berries have low PPO activity.

Bananas Versus Berries

Participants drank a banana based smoothie, a mixed berry smoothie, and a flavanol capsule used as a control. The researchers then analyzed blood and urine samples to see how much of the flavanols became available in the body.

The difference was striking. People who drank the banana smoothie had 84% lower flavanol levels compared with the control. In contrast, the low PPO mixed berry smoothie produced flavanol levels similar to the capsule control.

"We were really surprised to see how quickly adding a single banana decreased the level of flavanols in the smoothie and the levels of flavanol absorbed in the body," Ottaviani said. "This highlights how food preparation and combinations can affect the absorption of dietary compounds in foods."

The study also included a second test in which participants consumed flavanols along with a high PPO banana drink, but the ingredients were kept from contacting each other before intake. Flavanol levels were still reduced, which suggests PPO activity may continue to matter after consumption, possibly in the stomach.

What This Means for Your Smoothie

The findings do not mean bananas are bad for you. Bananas provide fiber, potassium, and other nutrients, and they can still be part of a healthy diet. The more specific lesson is that bananas may not be the best choice when the goal is to maximize flavanol intake from berries, grapes, cocoa, or other flavanol rich foods.

The Academy of Nutrition and Dietetics has issued a dietary recommendation suggesting 400 to 600 milligrams of flavanols per day for cardiometabolic health. Those compounds are found in foods such as tea, apples, berries, grapes, and cocoa.

For people trying to boost flavanols through smoothies, Ottaviani recommends pairing flavanol rich fruits like berries with ingredients that have low PPO activity. Good options include pineapple, oranges, mango, or yogurt.

Bananas can still be eaten on their own or used in smoothies where flavanol intake is not the main goal. But if your smoothie is built around berries, grapes, or cocoa, the better strategy may be to leave the banana out or enjoy it separately.

A Small Study With a Practical Message

The original study was controlled and carefully designed, but it was also small. The first part included eight healthy men, and a second test included 11 participants. That means the results are useful and intriguing, but they should not be treated as the final word for every person or every diet.

Nutrition experts commenting on the research have also urged people not to overreact. Smoothies with bananas can still be nutritious, especially as part of a varied diet. Individual digestion, food patterns, and overall nutrient intake all matter.

The best takeaway is simple: ingredient combinations can change what your body gets from food. A smoothie is not just a pile of nutrients in a glass. How the ingredients interact can affect the final nutritional payoff.

Why Flavanols Remain a Hot Research Topic

The smoothie finding fits into a larger area of nutrition research focused on flavanols and other plant bioactives. These compounds are being studied for possible benefits related to blood flow, blood pressure, cholesterol, glucose regulation, and brain health. The Academy of Nutrition and Dietetics guideline described moderate evidence for 400 to 600 milligrams per day of flavanols to support cardiometabolic health, while emphasizing food sources rather than supplements.

Recent cocoa flavanol research has produced a more nuanced picture for cognition. In the COSMOS related research program, cocoa extract containing 500 milligrams of flavanols per day did not show broad cognitive benefits for everyone, but some analyses suggested potential benefit among older adults with lower habitual diet quality.

That makes the smoothie study especially practical. If people are choosing berries, cocoa, or grapes for their flavanols, then preparation and pairing may matter. More research is still needed, but the idea is easy to apply at home.

Better Smoothie Combos for Flavanols

If the goal is a flavanol friendly smoothie, try combining berries with low PPO ingredients such as mango, pineapple, orange, or yogurt. These options can keep the drink sweet and creamy without adding the high PPO activity found in bananas.

For banana lovers, there is no need to give them up. Just consider separating your smoothie goals. Use bananas when you want creaminess, potassium, and sweetness. Use berries, cocoa, grapes, or apples with lower PPO partners when you want to preserve more flavanols.

The research may also point beyond smoothies. Ottaviani said tea, another major source of flavanols, could be affected by preparation methods that change how many flavanols are available for absorption.

"This is certainly an area that deserves more attention in the field of polyphenols and bioactive compounds in general," said Ottaviani.

Jodi Ensunsa, Reedmond Fong, Jennifer Kimball and Alan Crozier, all affiliated with the UC Davis Department of Nutrition and researchers affiliated with the UC Davis Department of Internal Medicine, University of Reading, King Saud University and Mars, Inc. contributed to the research.

The study was funded by a research grant from Mars, Inc., which collaborates with researchers to study potential benefits of cocoa flavanols for human health.

Journal Reference:

1. Javier I. Ottaviani, Jodi L. Ensunsa, Reedmond Y. Fong, Jennifer Kimball, Valentina Medici, Gunter G. C. Kuhnle, Alan Crozier, Hagen Schroeter, Catherine Kwik-Uribe. Impact of polyphenol oxidase on the bioavailability of flavan-3-ols in fruit smoothies: a controlled, single blinded, cross-over study. Food, 2023; 14 (18): 8217 DOI: 10.1039/D3FO01599H

For first time, Americans are getting more of their electricity from solar than coal

This is despite Trump's push for more coal use and his war on green energy

Tik Root, Senior Staff Writer

"This story was originally published by Grist. Sign up for Grist's weekly newsletter here."

Solar energy just provided more electricity in the United States than coal for the first time on record — marking a milestone for the rise of renewables in America. 

While gas and nuclear plants still lead the country’s energy mix, solar contributed 12.8 percent of the nation’s electrons in May, according to an analysis of government data by Ember, an energy think tank. Coal, meanwhile, provided just 12.2 percent. Just five years ago, solar was less than half of its current levels and coal was at 20 percent. 

It's Easy To Create Lots of Shitty Jobs

So don't break out the champagne about Friday's jobs report

Robert Reich

Friday’s jobs report — showing that America added 172,000 jobs in May — stimulated a lot of celebratory bullsh*t.

Trump said, “It’s raining jobs!” White House National Economic Council Director Kevin Hassett claimed the job market is "hitting on all cylinders.” The mainstream media called it a “blowout jobs report,” “stronger-than-expected jobs data,” the labor market’s “best three-month stretch in more than two years.”

What all this acclaim left out was that wages are falling relative to prices.

Average hourly earnings for private-sector production and non-supervisory workers — that is, for most employees — rose by only 8 cents (or 0.2 percent) in May. That’s the weakest pace of wage growth since 2021.

Meanwhile, prices are rising quickly — by around 3.8 percent annually. Hence, real wages — that is, their actual purchasing power — are dropping. The paychecks of most American workers aren’t covering rising costs. They’re getting poorer.

Included in the Cross' Mills Library Garden Tour...

 

Dear Arrowhead Patients and Fellow Gardeners,  The Cross’ Mills Public Library will be holding its beloved Gardens by the Sea Tour on Saturday, June 20th, from 10:00 AM to 4:00 PM, rain or shine. This special fundraiser features twelve beautiful local gardens on display, offering inspiration and enjoyment for gardeners of all levels. I am honored to share that my garden is included as one of the featured stops on this year’s tour. It’s a wonderful opportunity to explore unique landscapes, gather ideas, and celebrate the beauty of our local community. Tickets are $30, and all proceeds directly support the Cross’ Mills Public Library and its ongoing programs and services. If you, your family, or friends are interested in attending, tickets can be purchased online through the Cross’ Mills Library website or in person at the library. We hope you can join us for this special event and enjoy a relaxing and inspiring summer day! Thank you, and have a great summer. Click here for Garden Tour Tickets! Thank you and have a great summer, Dr. Bruce Gouin

Arrowhead Dental Associates | 4995 South County Trail | Charlestown, RI 02813 US

What do Charlestown’s Watchaug Pond and the Reflecting Pool in Washington have in common?

Dangerous algae bloom

RIDOH and DEM Recommend Avoiding Contact with Watchaug Pond

This morning in DC, workers poured bottles of peroxide
into the Reflecting Pool just days after the $14 million
repair job ordered by Donald Trump was completed.

The Rhode Island Department of Health (RIDOH) and Rhode Island Department of Environmental Management (DEM) are advising people to avoid contact with Watchaug Pond in Charlestown due to harmful algae blooms (HABs).  Water samples were collected by DEM and tested by RIDOH’s State Health Laboratories.

All recreation, including swimming, fishing, boating and kayaking, is high risk to health and recommended to be avoided at this location. This HAB is caused by blue-green algae, also known as cyanobacteria, which are naturally present in bodies of water. HABs can produce toxins which can be harmful to humans and animals.

Use caution in all areas of Watchaug Pond as HABs can move locations in ponds and lakes. Initial samples collected at Watchaug Pond exceeded the advisory threshold. People should not drink untreated water or eat fish from affected waterbodies. Pet owners should not allow pets to drink or swim in this water. 

This is going to take a LOT off peroxide!

This advisory recommendation remains in effect until further notice. To confirm the water is free from toxins and high cell counts, water samples will be collected to lift the advisory when the bloom has cleared from the affected waterbody.

Skin contact with water containing HABs can cause symptoms such as skin rashes, sore throat and irritation of the eyes and nose. Swallowing water containing HABs can cause stomachache, diarrhea, vomiting and nausea. More serious, but less common health effects associated with swallowing contaminated water may affect the liver and nervous system, cause irregular heartbeat, dizziness, or seizures.

Young children, pets and people with certain underlying health conditions or who are immunocompromised may be at greater risk for illness. Anyone who experiences symptoms after contact with water containing HABs should contact a healthcare provider.

If you or your pet come into contact with an algal bloom (HAB):

• Rinse your skin with clean water right away.
• Shower and wash your clothes when you get home.
• If your pet was exposed, wash it with clean water immediately and don’t let it lick algae from its fur.
• Call a vet if your pet shows signs of illness like tiredness, no eating, vomiting, diarrhea or other symptoms within a day.
• If you feel sick after contact, call a healthcare provider.

Affected waters may exhibit bright to dark green scum along the shoreline, with thick algae floating on the surface. It may resemble green paint, pea soup, or green cottage cheese. If you see water like this, people and pets should avoid contact with the water.

To report suspected blue-green algae blooms, contact DEM’s Office of Water Resources at DEM.OWRCyano@dem.ri.gov  or call 401-222-4700, Press 3, and select Office of Water Resources. If possible, send a photograph of the reported algae bloom. For more information and the Cyanobacteria Tracker Dashboard that lists current advisories and data, visit: www.dem.ri.gov/bluegreen

Trump Bought Tobacco Stocks and Raked In Industry Donations as FDA Eased Standards

Figures Trump would profit from cancer sticks

By Darius Tahir

Donald Trump, who once declared he had “saved” flavored vapes, grew his stock holdings this year to as much as $1.64 million in tobacco giant Philip Morris.

He also had holdings in Altria and a third leading tobacco company, though an apparent discrepancy in his disclosures clouds the extent of his investments. In 2025, tobacco interests donated $6 million to MAGA Inc., a super PAC that supports the president, and Trump’s inauguration. And, on April 30, a week before FDA guidance that provided a critical boost to the industry, Reynolds American dropped an additional $5 million into the super PAC's coffers.

The stock trades and political contributions occurred as the Trump administration pursued a broadly pro-tobacco agenda: Its FDA piloted a fast-track program to approve nicotine pouches. It unveiled a program to allow vapes on the market more rapidly, despite resistance from career civil servants and leadership, culminating this year in guidance waving through flavored electronic cigarettes. It cut public health employees focusing on anti-tobacco policy. And it broadened enforcement against illicit e-cigarettes, competitors to the big industry players with a financial relationship to Trump.

It amounts to the most pro-tobacco, pro-nicotine presidency in some time — a remarkable policy given the tens of millions of deaths cigarettes caused during the 20th century. Even in recent years, anti-smoking groups say a half-million Americans a year die from cigarettes. Industry advocates say the toll helps justify a shift to e-cigarettes and nicotine pouches, which they say are less harmful. However, public health advocates say these products carry their own risks, such as addiction.

Lawmakers and public health leaders have criticized the recent FDA guidance and approvals as a “lucrative payday” that ignored scientific evidence to deliver what investment analysts have described as “very positive” steps for influential tobacco companies.

The scale of the money is “unprecedented and problematic,” said Brian King, who was pushed out of the FDA’s tobacco office last April and now works as an executive at the Campaign for Tobacco-Free Kids. He fears that steering public policy toward tobacco — still addictive and harmful to health — puts Americans at risk.

“It's a gift on a platter with a side of public health malpractice,” he said.

Doctors May Need To Rethink Calcium and Vitamin D Recommendations After Major Review

Might not really help prevent broken bones

By BMJ Group

Calcium and vitamin D supplements, whether taken separately or together, provide little to no meaningful benefit in preventing fractures or falls in most older adults, according to a major review published in The BMJ.

Nearly one in three adults age 65 and older experiences a fall each year. Many of these falls lead to fractures, which can cause pain, lower quality of life, and increase the need for assisted living or residential care. As a result, reducing falls and fractures remains a major public health goal worldwide.

Earlier reviews have also found little evidence that calcium or vitamin D supplements reduce fracture risk, and findings on combined supplementation have been inconsistent. The role of vitamin D in preventing falls has also remained uncertain.

Even so, many doctors, health guidelines, and regulatory agencies continue to recommend vitamin D supplements, with or without calcium, to support bone health. Prescriptions for these supplements have also risen significantly in recent years.

Feds restore home energy rebates, but with a catch

Among other things, heat pumps take a hit

By Dan Gearino

Major new limits on eligibility

This article originally appeared on Inside Climate News, a nonprofit, non-partisan news organization that covers climate, energy and the environment. Sign up for their newsletter here.

Federal energy efficiency rebate programs will no longer cover a switch from fossil fuels to electricity for heating, according to long-awaited guidance from the Department of Energy.

The department published an update on how it will implement consumer programs with $8.8 billion in funding. The new provisions include eliminating use of diversity, equity and inclusion considerations, among other changes.

This follows legal challenges after Donald Trump issued an executive order last year, upon returning to office, canceling the release of funds from President Joe Biden’s Inflation Reduction Act, including rebates for home energy efficiency. A coalition of states successfully sued to restore the funding, obtaining an injunction in March 2025.

States have been waiting for the Department of Energy to reopen funding, a process that begins with this latest publication.

Clean energy and environmental advocates said the guidance was overdue and severely flawed.

The Non-Victory

Compared to where we were before February 28, it's a terrible failure

Robert Reich

Trump again claims victory in Iran. He’s claimed victory before, but now he has a so-called “agreement” with Iran.

That agreement, which appears to be no more than a memo of understanding — that is, a set of principles to which Iran and the United States have agreed — stops the fighting and reopens the Strait of Hormuz but it does not deal with the issue that caused Trump to initiate the conflict: Iran’s nuclear program.

Keep that in mind as you hear various renditions of what’s been decided. Recall that the Strait of Hormuz was open before Trump began bombing Iran. 

At best, the agreement Trump is touting restores the status quo to where it was when he commenced hostilities. Remember also that Iran had agreed to limit its development of nuclear-grade materials in its treaty with the Obama administration, which Trump revoked in 2018.

So what has been accomplished? Iran now is under the control of a more extremist regime than when Trump started this war. 

Oil prices are far higher, and will take some time to return to where they were before it began (if they ever do). 

Meanwhile, Trump has caused the United States to be more dependent on fossil fuels than we were prior to his inauguration for a second time, and the high oil prices brought on by his war has enriched Vladimir Putin’s regime.

The war with Iran has cost the United States an estimated $90 billion, and that’s a conservative estimate. It has caused widespread suffering throughout the Middle East. 

It has put Israel in a more precarious situation than it was before — and much of that is due to Benjamin Netanyahu, who is not a party to, and has not approved, the agreement.

This doesn’t look like a victory. Compared to where the United States and the Middle East were on February 28, when Trump began this war, it’s a terrible failure.

Can't imagine

Wednesday protest in Westerly

Trump screwed up

Cut funding of program to detect and block screwworm infections

Stephanie Soucheray, MA

US Department of Agriculture (USDA) officials have confirmed New World screwworm (NWS) in a dog in New Mexico, and Texas has three more detections, in a goat and two calves. So far, the United States has six detections of the parasitic fly in the past week. 

The first two detections were announced last week were in Zavala, Texas, but the three new detections show the insect has infiltrated more territory in the United States, including La Salle County, Texas (two calves), Gillespie County, Texas (goat), and now Lea County, New Mexico (dog). 

Confirmed NWS infections in animals are also now farther from the US border with Mexico, which has reported more than 27,000 cases through June 3, according to USDA data.

Caused by the larvae of Cochliomyia hominivorax, a parasitic fly, NWS is a serious threat to livestock, wildlife, pets, and, in rare cases, people. The larvae (maggots) burrow into the living tissue of any warm-blooded animals, causing severe wounds and infections, and infection can be fatal. 

This situation is evolving, and we expect new information to emerge.

“This situation is evolving, and we expect new information to emerge as our investigation continues,” said Dudley Hoskins, USDA undersecretary for marketing and regulatory programs. “USDA is committed to sharing what we learn quickly, accurately, and transparently so animal owners and local communities have the information they need to stay vigilant.

“We are working closely with our partners in New Mexico, Texas, and across the region to ensure we identify, contain, and respond to any potential cases as swiftly as possible.” 

Aquatic Weed Treatment Scheduled for Meadowbrook Pond

No fishing on Thursday, then watch notices

The Rhode Island Department of Environmental Management (DEM) announces that Meadowbrook Pond, Richmond will receive treatments to control infestations of invasive aquatic plants on Thursday, June 18.

Anglers and boaters should avoid using the lake during the treatment. Signs will be posted with information about temporary water use advisories. 

Neighbors and other users of the pond should keep pets from drinking the water for at least three days. 

This treatment will target invasive plants in particular, variable water milfoil and curly-leaf pondweed, and it will not harm fish or other aquatic life. Meadowbrook Pond is popular with anglers and boaters and is stocked with trout several times per year.

RFK Jr. Seeks To Peek at Americans’ Medical Records for Clues on Autism and Vaccines

NO!

By Amanda Seitz and Darius Tahir

U.S. health secretary Robert F. Kennedy Jr. is pursuing federal government access to most Americans’ medical records, in a quest to research a link between vaccines and autism — a connection the medical establishment studied for decades and flatly rejects.

The Department of Health and Human Services is seeking data from little-known state systems that allow hospitals and clinics to exchange detailed, identifiable patient information, KFF Health News has learned.

In private meetings, some public health leaders have objected to giving Kennedy’s team access to such data, raising doubts that it’s legal or that the information would even be useful.

They have also expressed concerns about allowing the federal government to peer into the minutiae of Americans’ medical records, which could mean viewing anything from doctors’ notes to prescription history. HHS has offered no insight into how it will protect or handle the personal health information it obtains.

But Kennedy told KFF Health News that medical records are key to investigating the cause of autism, vaccine safety, and chronic diseases. And millions of dollars in grant money has poured into a Nebraska nonprofit that has assisted Kennedy’s effort, according to state records.

He and his advisers have been frustrated that federal access to Americans’ medical records has been limited.

“We need a good health record system, and one of the things that really surprised me most when I came into office is that there is — that the systems are broken,” Kennedy said in a May interview. “We’ve had to go to the states and, luckily, we’ve got a lot of cooperation from the states, but we now have databases together that we can actually do the studies on. Those studies are in motion.”

HHS has not publicly announced any new projects involving medical records and autism or vaccine research. Kennedy faced blowback last year when he proposed compiling the medical records of people with autism to create a federal disease registry — which health department officials later disputed was underway.

But Kennedy said in May, “We have a whole pipeline of studies that will be done over the next year.”